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Pilot comparative study on the health of vaccinated and unvaccinated 6-to 12-year-old U.S. children

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  • Chalfont Research Institute

Abstract and Figures

Vaccinations have prevented millions of infectious illnesses, hospitalizations and deaths among U.S. children, yet the long-term health outcomes of the vaccination schedule remain uncertain. Studies have been recommended by the U.S. Institute of Medicine to address this question. This study aimed 1) to compare vaccinated and unvaccinated children on a broad range of health outcomes, and 2) to determine whether an association found between vaccination and neurodevelopmental disorders (NDD), if any, remained significant after adjustment for other measured factors. A cross-sectional study of mothers of children educated at home was carried out in collaboration with homeschool organizations in four U.S. states: Florida, Louisiana, Mississippi and Oregon. Mothers were asked to complete an anonymous online questionnaire on their 6-to 12-year-old biological children with respect to pregnancy-related factors, birth history, vaccinations, physician-diagnosed illnesses, medications used, and health services. NDD, a derived diagnostic measure, was defined as having one or more of the following three closely-related diagnoses: a learning disability, Attention Deficient Hyperactivity Disorder, and Autism Spectrum Disorder. A convenience sample of 666 children was obtained, of which 261 (39%) were unvaccinated. The vaccinated were less likely than the unvaccinated to have been diagnosed with chickenpox and pertussis, but more likely to have been diagnosed with pneumonia, otitis media, allergies and NDD. After adjustment, vaccination, male gender, and preterm birth remained significantly associated with NDD. However, in a final adjusted model with interaction, vaccination but not preterm birth remained associated with NDD, while the interaction of preterm birth and vaccination was associated with a 6.6-fold increased odds of NDD (95% CI: 2.8, 15.5). In conclusion, vaccinated homeschool children were found to have a higher rate of allergies and NDD than unvaccinated homeschool children. While vaccination remained significantly associated with NDD after controlling for other factors, preterm birth coupled with vaccination was associated with an apparent synergistic increase in the odds of NDD. Further research involving larger, independent samples and stronger research designs is needed to verify and understand these unexpected findings in order to optimize the impact of vaccines on children's health.
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Research Article
Journal of Translational Science
J Transl Sci, 2017 doi: 10.15761/JTS.1000186 Volume 3(3): 1-12
ISSN: 2059-268X
Pilot comparative study on the health of vaccinated and
unvaccinated 6- to 12-year-old U.S. children
Anthony R Mawson1*, Brian D Ray2, Azad R Bhuiyan3 and Binu Jacob4
1Professor, Department of Epidemiology and Biostatistics, School of Public Health, Jackson State University, Jackson, MS 39213, USA
2President, National Home Education Research Institute, PO Box 13939, Salem, OR 97309, USA
3Associate Professor, Department of Epidemiology and Biostatistics, School of Public Health, Jackson State University, Jackson, MS 39213, USA
4Former graduate student, Department of Epidemiology and Biostatistics School of Public Health, Jackson State University, Jackson, MS 39213, USA
Abstract
Vaccinations have prevented millions of infectious illnesses, hospitalizations and deaths among U.S. children, yet the long-term health outcomes of the vaccination
schedule remain uncertain. Studies have been recommended by the U.S. Institute of Medicine to address this question. is study aimed 1) to compare vaccinated and
unvaccinated children on a broad range of health outcomes, and 2) to determine whether an association found between vaccination and neurodevelopmental disorders
(NDD), if any, remained signicant after adjustment for other measured factors. A cross-sectional study of mothers of children educated at home was carried out
in collaboration with homeschool organizations in four U.S. states: Florida, Louisiana, Mississippi and Oregon. Mothers were asked to complete an anonymous
online questionnaire on their 6- to 12-year-old biological children with respect to pregnancy-related factors, birth history, vaccinations, physician-diagnosed illnesses,
medications used, and health services. NDD, a derived diagnostic measure, was dened as having one or more of the following three closely-related diagnoses: a
learning disability, Attention Decient Hyperactivity Disorder, and Autism Spectrum Disorder. A convenience sample of 666 children was obtained, of which 261
(39%) were unvaccinated. e vaccinated were less likely than the unvaccinated to have been diagnosed with chickenpox and pertussis, but more likely to have been
diagnosed with pneumonia, otitis media, allergies and NDD. After adjustment, vaccination, male gender, and preterm birth remained signicantly associated with
NDD. However, in a nal adjusted model with interaction, vaccination but not preterm birth remained associated with NDD, while the interaction of preterm
birth and vaccination was associated with a 6.6-fold increased odds of NDD (95% CI: 2.8, 15.5). In conclusion, vaccinated homeschool children were found to have
a higher rate of allergies and NDD than unvaccinated homeschool children. While vaccination remained signicantly associated with NDD after controlling for
other factors, preterm birth coupled with vaccination was associated with an apparent synergistic increase in the odds of NDD. Further research involving larger,
independent samples and stronger research designs is needed to verify and understand these unexpected ndings in order to optimize the impact of vaccines on
children’s health.
Abbreviations: ADHD: Attention Decit Hyperactivity Disorder;
ASD: Autism Spectrum Disorder; AOM: Acute Otitis Media; CDC:
Centers for Disease Control and Prevention; CI: Condence Interval;
NDD: Neurodevelopmental Disorders; NHERI: National Home Education
Research Institute; OR: Odds Ratio; PCV-7: Pneumococcal Conjugate
Vaccine-7; VAERS: Vaccine Adverse Events Reporting System.
Introduction
Vaccines are among the greatest achievements of biomedical
science and one of the most eective public health interventions of the
20th century [1]. Among U.S. children born between 1995 and 2013,
vaccination is estimated to have prevented 322 million illnesses, 21 million
hospitalizations and 732,000 premature deaths, with overall cost savings of
$1.38 trillion [2]. About 95% of U.S. children of kindergarten age receive
all of the recommended vaccines as a requirement for school and daycare
attendance [3,4], aimed at preventing the occurrence and spread of targeted
infectious diseases [5]. Advances in biotechnology are contributing to the
development of new vaccines for widespread use [6].
Under the currently recommended pediatric vaccination schedule
[7], U.S. children receive up to 48 doses of vaccines for 14 diseases
from birth to age six years, a gure that has steadily increased since
the 1950s, most notably since the Vaccines for Children program
was created in 1994. e Vaccines for Children program began with
vaccines targeting nine diseases: diphtheria, tetanus, pertussis, polio,
Haemophilus inuenzae type b disease, hepatitis B, measles, mumps,
and rubella. Between 1995 and 2013, new vaccines against ve other
diseases were added for children age 6 and under: varicella, hepatitis A,
pneumococcal disease, inuenza, and rotavirus vaccine.
Although short-term immunologic and safety testing is performed
on vaccines prior to their approval by the U.S. Food and Drug
Administration, the long-term eects of individual vaccines and of
the vaccination program itself remain unknown [8]. Vaccines are
acknowledged to carry risks of severe acute and chronic adverse eects,
such as neurological complications and even death [9], but such risks
are considered so rare that the vaccination program is believed to be
safe and eective for virtually all children [10].
ere are very few randomized trials on any existing vaccine
recommended for children in terms of morbidity and mortality, in
*Correspondence to: Anthony R Mawson, Professor, Department of
Epidemiology and Biostatistics, School of Public Health, Jackson State
University, Jackson, MS 39213, USA, E-mail: Anthony.r.mawson@jsums.edu
Key words: acute diseases, chronic diseases, epidemiology, evaluation, health
policy, immunization, neurodevelopmental disorders, vaccination
Received: March 22, 2017; Accepted: April 21, 2017; Published: April 24, 2017
Mawson AR (2017) Pilot comparative study on the health of vaccinated and unvaccinated 6- to 12-year-old U.S. children
J Transl Sci, 2017 doi: 10.15761/JTS.1000186 Volume 3(3): 2-12
part because of ethical concerns involving withholding vaccines from
children assigned to a control group. One exception, the high-titer
measles vaccine, was withdrawn aer several randomized trials in west
Africa showed that it interacted with the diphtheria-tetanus-pertussis
vaccine, resulting in a signicant 33% increase in child mortality [11].
Evidence of safety from observational studies includes a limited number
of vaccines, e.g., the measles, mumps and rubella vaccine, and hepatitis
B vaccine, but none on the childhood vaccination program itself.
Knowledge is limited even for vaccines with a long record of safety and
protection against contagious diseases [12]. e safe levels and long-
term eects of vaccine ingredients such as adjuvants and preservatives
are also unknown [13]. Other concerns include the safety and cost-
eectiveness of newer vaccines against diseases that are potentially
lethal for individuals but have a lesser impact on population health,
such as the group B meningococcus vaccine [14].
Knowledge of adverse events following vaccinations is largely
based on voluntary reports to the Vaccine Adverse Events Reporting
System (VAERS) by physicians and parents. However, the rate of
reporting of serious vaccine injuries is estimated to be <1% [15]. ese
considerations led the former Institute of Medicine (now the National
Academy of Medicine) in 2005 to recommend the development of a
ve-year plan for vaccine safety research by the Centers for Disease
Control and Prevention (CDC) [16,17]. In its 2011 and 2013 reviews
of the adverse eects of vaccines, the Institute of Medicine concluded
that few health problems are caused by or associated with vaccines, and
found no evidence that the vaccination schedule was unsafe [18,19].
Another systematic review, commissioned by the US Agency for
Healthcare Research and Quality to identify gaps in evidence on the
safety of the childhood vaccination program, concluded that severe
adverse events following vaccinations are extremely rare [20]. e
Institute of Medicine, however, noted that studies were needed: to
compare the health outcomes of vaccinated and unvaccinated children;
to examine the long-term cumulative eects of vaccines; the timing of
vaccination in relation to the age and condition of the child; the total
load or number of vaccines given at one time; the eect of other vaccine
ingredients in relation to health outcomes; and the mechanisms of
vaccine-associated injury [19].
A complicating factor in evaluating the vaccination program is
that vaccines against infectious diseases have complex nonspecic
eects on morbidity and mortality that extend beyond prevention of
the targeted disease. e existence of such eects poses a challenge
to the assumption that individual vaccines aect the immune system
independently of each other and have no physiological eect other
than protection against the targeted pathogen [21]. e nonspecic
eects of some vaccines appear to be benecial, while in others they
appear to increase morbidity and mortality [22,23]. For instance, both
the measles and Bacillus Calmette–Guérin vaccine reportedly reduce
overall morbidity and mortality [24], whereas the diphtheria-tetanus-
pertussis [25] and hepatitis B vaccines [26] have the opposite eect.
e mechanisms responsible for these nonspecic eects are unknown
but may involve inter alia: interactions between vaccines and their
ingredients, e.g., whether the vaccines are live or inactivated; the most
recently administered vaccine; micronutrient supplements such as
vitamin A; the sequence in which vaccines are given; and their possible
combined and cumulative eects [21].
A major current controversy is the question of whether vaccination
plays a role in neurodevelopmental disorders (NDDs), which broadly
include learning disabilities, Attention Decit Hyperactivity Disorder
(ADHD) and Autism Spectrum Disorder (ASD). e controversy has
been fueled by the fact that the U.S. is experiencing what has been
described as a “silent pandemic” of mostly subclinical developmental
neurotoxicity, in which about 15% of children suer from a learning
disability, sensory decits, and developmental delays [27,28]. In 1996
the estimated prevalence of ASD was 0.42%. By 2010 it had risen to
1.47% (1 in 68), with 1 in 42 boys and 1 in 189 girls aected [29].
More recently, based on a CDC survey of parents in 2011–2014,
2.24% of children (1 in 45) were estimated to have ASD. Rates of other
developmental disabilities, however, such as intellectual disability,
cerebral palsy, hearing loss, and vision impairments, have declined
or remained unchanged [30]. Prevalence rates of Attention Decit
Hyperactivity Disorder (ADHD) have also risen markedly in recent
decades [31]. Earlier increases in the prevalence of learning disability
have been followed by declining rates in most states, possibly due to
changes in diagnostic criteria [32].
It is believed that much of the increase in NDD diagnoses in
recent decades has been due to growing awareness of autism and more
sensitive screening tools, and hence to greater numbers of children
with milder symptoms of autism. But these factors do not account
for all of the increase [33]. e geographically widespread increase in
ASD and ADHD suggests a role for an environmental factor to which
virtually all children are exposed. Agricultural chemicals are a current
focus of research [34-37].
A possible contributory role for vaccines in the rise in NDD
diagnoses remains unknown because data on the health outcomes of
vaccinated and unvaccinated children are lacking. e need for such
studies is suggested by the fact that the Vaccine Injury Compensation
Program has paid $3.2 billion in compensation for vaccine injury since
its creation in 1986 [38]. A study of claims compensated by the Vaccine
Injury Compensation Program for vaccine-induced encephalopathy
and seizure disorder found 83 claims that were acknowledged as being
due to brain damage. In all cases it was noted by the Court of Federal
Claims, or indicated in settlement agreements, that the children had
autism or ASD [39]. On the other hand, numerous epidemiological
studies have found no association between receipt of selected vaccines
(in particular the combined measles, mumps, and rubella vaccine)
and autism [10,40-45], and there is no accepted mechanism by which
vaccines could induce autism [46].
A major challenge in comparing vaccinated and unvaccinated
children has been to identify an accessible pool of unvaccinated
children, since the vast majority of children in the U.S. are vaccinated.
Children educated at home (“homeschool children”) are suitable
for such studies as a higher proportion are unvaccinated compared
to public school children [47]. Homeschool families have an
approximately equal median income to that of married-couple families
nationwide, somewhat more years of formal education, and a higher
average family size (just over three children) compared to the national
average of just over two children [48-50]. Homeschooling families
are slightly overrepresented in the south, about 23% are nonwhite,
and the age distribution of homeschool children in grades K-12 is
similar to that of children nationwide [51]. About 3% of the school-age
population was homeschooled in the 2011-2012 school year [52].
e aims of this study were 1) to compare vaccinated and
unvaccinated children on a broad range of health outcomes, including
acute and chronic conditions, medication and health service
utilization, and 2) to determine whether an association found between
vaccination and NDDs, if any, remained signicant aer adjustment
for other measured factors.
Mawson AR (2017) Pilot comparative study on the health of vaccinated and unvaccinated 6- to 12-year-old U.S. children
J Transl Sci, 2017 doi: 10.15761/JTS.1000186 Volume 3(3): 3-12
Methods
Study planning
To implement the study, a partnership was formed with the
National Home Education Research Institute (NHERI), an organization
that has been involved in educational research on homeschooling for
many years and has strong and extensive contacts with the homeschool
community throughout the country (www.nheri.org). e study
protocol was approved by the Institutional Review Board of Jackson
State University.
Study design
e study was designed as a cross-sectional survey of homeschooling
mothers on their vaccinated and unvaccinated biological children ages 6
to 12. As contact information on homeschool families was unavailable,
there was no dened population or sampling frame from which a
randomized study could be carried out, and from which response
rates could be determined. However, the object of our pilot study was
not to obtain a representative sample of homeschool children but a
convenience sample of unvaccinated children of sucient size to test
for signicant dierences in outcomes between the groups.
We proceeded by selecting 4 states (Florida, Louisiana, Mississippi,
and Oregon) for the survey (Stage 1). NHERI compiled a list of
statewide and local homeschool organizations, totaling 84 in Florida,
18 in Louisiana, 12 in Mississippi and 17 in Oregon. Initial contacts
were made in June 2012. NHERI contacted the leaders of each statewide
organization by email to request their support. A second email was
then sent, explaining the study purpose and background, which the
leaders were asked to forward to their members (Stage 2). A link was
provided to an online questionnaire in which no personally identifying
information was requested. With funding limited to 12 months, we
sought to obtain as many responses as possible, contacting families
only indirectly through homeschool organizations. Biological mothers
of children ages 6-12 years were asked to serve as respondents in order
to standardize data collection and to include data on pregnancy-related
factors and birth history that might relate to the children's current
health. e age-range of 6 to 12 years was selected because most
recommended vaccinations would have been received by then.
Recruitment and informed consent
Homeschool leaders were asked to sign Memoranda of Agreement
on behalf of their organizations and to provide the number of member
families. Non-responders were sent a second notice but few provided
the requested information. However, follow-up calls to the leaders
suggested that all had contacted their members about the study. Both
the letter to families and the survey questions were stated in a neutral
way with respect to vaccines. Our letter to parents began:
“Dear Parent, is study concerns a major current health question:
namely, whether vaccination is linked in any way to children's long-term
health. Vaccination is one of the greatest discoveries in medicine, yet
little is known about its long-term impact. e objective of this study
is to evaluate the eects of vaccination by comparing vaccinated and
unvaccinated children in terms of a number of major health outcomes …”
Respondents were asked to indicate their consent to participate, to
provide their home state and zip code of residence, and to conrm that
they had biological children 6 to 12 years of age. e communications
company Qualtrics (http://qualtrics.com) hosted the survey website.
e questionnaire included only closed-ended questions requiring
yes or no responses, with the aim of improving both response and
completion rates.
A number of homeschool mothers volunteered to assist NHERI
promote the study to their wide circles of homeschool contacts. A
number of nationwide organizations also agreed to promote the study
in the designated states. e online survey remained open for three
months in the summer of 2012. Financial incentives to complete the
survey were neither available nor oered.
Denitions and measures
Vaccination status was classied as unvaccinated (i.e., no
previous vaccinations), partially vaccinated (received some but not
all recommended vaccinations) and fully vaccinated (received all
recommended age-appropriate vaccines), as reported by mothers.
ese categories were developed on the premise that any long-term
eects of vaccines would be more evident in fully-vaccinated than in
partially-vaccinated children, and rare or absent in the unvaccinated.
Mothers were asked to use their child’s vaccination records to indicate
the recommended vaccines and doses their child had received.
Dates of vaccinations were not requested in order not to overburden
respondents and to reduce the likelihood of inaccurate reporting; nor
was information requested on adverse events related to vaccines, as
this was not our purpose. We also did not ask about dates of diagnoses
because chronic illnesses are oen gradual in onset and made long aer
the appearance of symptoms. Since most vaccinations are given before
age 6, vaccination would be expected to precede the recognition and
diagnosis of most chronic conditions.
Mothers were asked to indicate on a list of more than 40 acute and
chronic illnesses all those for which her child or children had received
a diagnosis by a physician. Other questions included the use of health
services and procedures, dental check-ups, “sick visits” to physicians,
medications used, insertion of ventilation ear tubes, number of days
in the hospital, the extent of physical activity (number of hours the
child engaged in “vigorous” activities on a typical weekday), number
of siblings, family structure (mother and father living in the home,
divorced or separated), family income and/or highest level of education
of mother or father, and social interaction with children outside the
home (i.e., amount of time spent in play or other contact with children
outside the household). Questions specically for the mother included
pregnancy-related conditions and birth history, use of medications
during pregnancy, and exposure to an adverse environment (dened
as living within 1-2 miles of a furniture manufacturing factory,
hazardous waste site, or lumber processing factory). NDD, a derived
diagnostic category, was dened as having one or more of the following
three closely related and overlapping diagnoses: a learning disability,
Attention Decit Hyperactivity Disorder (ADHD) and Autism
Spectrum Disorder (ASD) [53].
Statistical methods
Unadjusted bivariate analyses using chi-square tests were
performed initially to test the null hypothesis of no association between
vaccination status and health outcomes, i.e., physician-diagnosed acute
and chronic illnesses, medications, and the use of health services. In
most analyses, partially and fully vaccinated children were grouped
together as the “vaccinated” group, with unvaccinated children as the
control group. e second aim of the study was to determine whether
any association found between vaccination and neurodevelopmental
disorders remained signicant aer controlling for other measured
factors. Descriptive statistics on all variables were computed to
determine frequencies and percentages for categorical variables and
means (± SD) for continuous variables. e strength of associations
Mawson AR (2017) Pilot comparative study on the health of vaccinated and unvaccinated 6- to 12-year-old U.S. children
J Transl Sci, 2017 doi: 10.15761/JTS.1000186 Volume 3(3): 4-12
between vaccination status and health outcomes were tested using odds
ratios (OR) and 95% Condence Intervals (CI). Odds ratios describe the
strength of the association between two categorical variables measured
simultaneously and are appropriate measures of that relationship in a
cross-sectional study [54]. Unadjusted and adjusted logistic regression
analyses were carried out using SAS (Version 9.3) to determine the
factors associated with NDDs.
Results
Socio-Demographic characteristics of respondents
e information contained in 415 questionnaires provided data
on 666 homeschool children. Table 1 shows the characteristics of
the survey respondents. Mothers averaged about 40 years of age,
were typically white, college graduates, with household incomes
between $50,000 to $100,000, Christian, and married. e reasons for
homeschooling for the majority of respondents (80-86%) were for a
moral environment, better family relationships, or for more contact
with their child or children.
e children as a group were similarly mostly white (88%), with
a slight preponderance of females (52%), and averaged 9 years of age.
With regard to vaccination status, 261 (39%) were unvaccinated, 208
(31%) were partially vaccinated, and 197 (30%) had received all of the
recommended vaccinations. All statistical analyses are based on these
numbers.
Acute illness
Vaccinated children (N=405), combining the partially and fully
vaccinated, were signicantly less likely than the unvaccinated to have
had chickenpox (7.9% vs. 25.3%, p <0.001; Odds Ratio = 0.26, 95%
Condence Interval: 0.2, 0.4) and whooping cough (pertussis) (2.5%
vs. 8.4%, p <0.001; OR 0.3, 95% CI: 0.1, 0.6), and less likely, but not
signicantly so, to have had rubella (0.3% vs. 1.9%, p = 0.04; OR 0.1,
95% CI: 0.01, 1.1). However, the vaccinated were signicantly more
likely than the unvaccinated to have been diagnosed with otitis media
(19.8% vs. 5.8%, p <0.001; OR 3.8, 95% CI: 2.1, 6.6) and pneumonia
(6.4% vs. 1.2%, p = 0.001; OR 5.9, 95% CI: 1.8, 19.7). No signicant
dierences were seen with regard to hepatitis A or B, high fever in
the past 6 months, measles, mumps, meningitis (viral or bacterial),
inuenza, or rotavirus (Table 2).
Chronic illness
Vaccinated children were signicantly more likely than the
unvaccinated to have been diagnosed with the following: allergic
rhinitis (10.4% vs. 0.4%, p <0.001; OR 30.1, 95% CI: 4.1, 219.3), other
allergies (22.2% vs. 6.9%, p <0.001; OR 3.9, 95% CI: 2.3, 6.6), eczema/
atopic dermatitis (9.5% vs. 3.6%, p = 0.035; OR 2.9, 95% CI: 1.4, 6.1), a
learning disability (5.7% vs. 1.2%, p = 0.003; OR 5.2, 95% CI: 1.6, 17.4),
ADHD (4.7% vs. 1.0%, p = 0.013; OR 4.2, 95% CI: 1.2, 14.5), ASD (4.7%
vs. 1.0%, p = 0.013; OR 4.2, 95% CI: 1.2, 14.5), any neurodevelopmental
disorder (i.e., learning disability, ADHD or ASD) (10.5% vs. 3.1%, p
<0.001; OR 3.7, 95% CI: 1.7, 7.9) and any chronic illness (44.0% vs.
25.0%, p <0.001; OR 2.4, 95% CI: 1.7, 3.3). No signicant dierences
were observed with regard to cancer, chronic fatigue, conduct disorder,
Crohn’s disease, depression, Types 1 or 2 diabetes, encephalopathy,
epilepsy, hearing loss, high blood pressure, inammatory bowel
disease, juvenile rheumatoid arthritis, obesity, seizures, Tourette’s
syndrome, or services received under the Individuals with Disabilities
Education Act (Table 3).
Partial versus full vaccination
Partially vaccinated children had an intermediate position between
the fully vaccinated and unvaccinated in regard to several but not
all health outcomes. For instance, as shown in Table 4, the partially
vaccinated had an intermediate (apparently detrimental) position in
terms of allergic rhinitis, ADHD, eczema, and learning disability.
Gender dierences in chronic illness
Among the vaccinated (combining partially and fully vaccinated
children), boys were more likely than girls to be diagnosed with a
chronic condition – signicantly so in the case of allergic rhinitis
(13.9% vs. 7.2%, p = 0.03; OR 2.1, 95% CI: 1.1, 4.1), ASD (7.7% vs. 1.9%,
p = 0.006; OR 4.3, 95% CI: 1.4, 13.2), and any neurodevelopmental
disorder (14.4% vs. 6.7%, p = 0.01; OR 2.3, 95% CI: 1.2, 4.6) (Table 5).
Use of medications and health services
e vaccinated (combining the partially and fully vaccinated) were
signicantly more likely than the unvaccinated to use medication for
allergies (20.0% vs. 1.2%, p <0.001; OR 21.5, 95% CI: 6.7, 68.9), to have
used antibiotics in the past 12 months (30.8% vs. 15.4%, p <0.001; OR
2.4, 95% CI: 1.6, 3.6), and to have used fever medications at least once
(90.7% vs. 67.8%, p <0.001; OR 4.6, 95% CI: 3.0, 7.1). e vaccinated
were also more likely to have seen a doctor for a routine checkup in the
past 12 months (57.6% vs. 37.2%, p <0.001; OR 2.3, 95% CI: 1.7, 3.2),
visited a dentist during the past year (89.4% vs. 80.5%, p <0.001; OR
2.0, 95% CI: 1.3, 3.2), visited a doctor or clinic due to illness in the past
year (36.0% vs. 16.0%, p <0.001; OR 3.0, 95% CI: 2.0, 4.4), been tted
with ventilation ear tubes (3.0% vs. 0.4%, p = 0.018; OR 8.0, 95% CI: 1.0,
66.1), and spent one or more nights in a hospital (19.8% vs. 12.3%, p =
0.012; OR 1.8, 95% CI: 1.1, 2.7) (Table 6).
Mean (SD) a
Age (n=407) 40.59 (6.7)
Number (%)a
Race
White 382 (92.5%)
Non-White 21 (7.6%)
Total 413
Education
High School Graduate or Less 35 (8.5%)
Some College 114 (27.5%)
College Graduate 187 (45.2%)
Post-Graduates 78 (18.5%)
Total 414
Total Gross Household Income
< $49,999 123 (30.8%)
$50,000-100,000 182 (45.5%)
> $100,000 95 (23.8%)
Total 400
Religious Aliation
Christianity 375 (91.2%)
Non-Christianity 36 (8.8%)
Total 411
Marital Status
Married 386 (93.7%)
Not Married 26 (6.3%)
Total 412
aMissing observations are excluded.
Table 1. Characteristics of the respondentsa
Mawson AR (2017) Pilot comparative study on the health of vaccinated and unvaccinated 6- to 12-year-old U.S. children
J Transl Sci, 2017 doi: 10.15761/JTS.1000186 Volume 3(3): 5-12
Vaccinated (n=405) Unvaccinated (n=261) Total (n=666) Chi-square P-value Odds Ratio (95% CI)
Chickenpox
Yes 32 (7.9%) 66 (25.3%) 98 (14.7%) 38.229 < 0.001 0.26 (0.2 - 0.4)
No 373 (92.1%) 195 (74.7%) 568 (85.3%)
Otitis media
Yes 80 (19.8%) 16(5.8%) 96 (14.4%) 26.643 < 0.001 3.8 (2.1 - 6.6)
No 325 (80.2%) 245 (94.2%) 507 (85.6%)
Pneumonia
Yes 26 (6.4%) 3 (1.2%) 29 (4.4%) 10.585 < 0.001 5.9 (1.8 - 19.7)
No 379 (93.6%) 258 (98.8%) 637 (95.6%)
Whooping cough
Yes 10 (2.5%) 22 (8.4%) 32 (4.8%) 12.326 < 0.001 0.3 (0.1 - 0.6)
No 395 (97.5%) 239 (91.6%) 634 (95.2%)
Rubella
Yes 1 (0.3%) 5 (1.9%) 6 (0.9%) 4.951 0.037 0.1 (0.01 - 1.1)
No 404 (99.6%) 256 (98.1%) 660 (99.1%)
Table 2. Vaccination status and health outcomes – Acute Conditions
Chronic Disease Vaccinated (n=405) Unvaccinated (n=261) Chi-square P-value Odds Ratio (95% CI)
Allergic rhinitis
Yes 42 (10.4%) 1 (0.4%) 26.21 < 0.001 30.1 (4.1 - 219.3)
363 (89.6%) 260 (99.6%)
Allergies
Yes 90 (22.2%) 18 (6.9%) 29.44 < 0.001 3.9 (2.3 - 6.6)
No 315 (77.9%) 243 (93.1%)
ADHD
Yes 19 (4.7%) 3 (1.0%) 6.23 0.013 4.2 (1.2 - 14.5)
No 386 (95.3%) 258 (99.0%)
ASD
Yes 19 (4.7%) 3 (1.0%) 6.23 0.013 4.2 (1.2 - 14.5)
No 386 (95.3%) 258 (99.0%)
Eczema (atopic dermatitis)
Yes 38 (9.5%) 9 (3.6%) 8.522 0.035 2.9 (1.4 - 6.1)
No 367 (90.5%) 252 (96.4%)
Learning Disability
Yes 23 (5.7%) 3 (1.2%) 8.6803 0.003 5.2 (1.6 - 17.4)
No 382 (94.3%) 258 (98.9%)
Neurodevelopment Disorder
Yes 42 (10.5%) 8 (3.1%) 12.198 < 0.001 3.7 (1.7 - 7.9)
No 313 (89.5%) 253 (96.9%)
Any Chronic Condition
Yes 178 (44.0%) 65 (24.9%) 24.8456 < 0.001 2.4 (1.7 - 3.3)
No 227 (56.0%) 196 (75.1%)
Table 3. Vaccination status and health outcomes – Chronic Conditions
Figure 1. The overlap and distribution of physician-diagnosed neurodevelopmental disorders, based on mothers’ reports
Mawson AR (2017) Pilot comparative study on the health of vaccinated and unvaccinated 6- to 12-year-old U.S. children
J Transl Sci, 2017 doi: 10.15761/JTS.1000186 Volume 3(3): 6-12
Unvaccinated (n=261) Partially Vaccinated
(n=208)
Fully Vaccinated
(n=197)
Total
(n=666) Chi-Square P-value
Chronic Conditions
Allergic rhinitis
Yes 1 (0.4%) 17 (8.2%) 25 (12.7%) 43 (6.5%) 29.6306 < 0.001
No 260 (99.6%) 191 (91.8%) 172 (87.3%) 623 (93.5%)
Allergies
Yes 18 (6.9%) 47 (22.6%) 43 (21.8%) 108 (16.2%) 27.4819 < 0.001
No 243 (93.1%) 161 (77.4%) 154 (78.2%) 558 (83.8%)
ADHD
Yes 3 (1.2%) 8 (3.9%) 11 (5.6%) 22 (3.3%) 7.1900 0.075
No 258 (98.8%) 200 (96.1%) 186 (94.4%) 644 (96.7%)
ASD
Yes 3 (1.2%) 11 (5.3%) 8 (4.6%) 22 (3.3%) 6.7109 0.034
No 258 (98.8%) 197 (94.7%) 189 (95.4%) 644 (96.7%)
Eczema (atopic
dermatitis)
Yes 9 (3.5%) 18 (8.7%) 20 (10.2%) 47 (7.1%) 8.8683 0.012
No 252 (96.5%) 190 (91.3%) 177 (89.8%) 619 (92.9%)
Learning Disability
Yes 3 (1.2%) 11 (5.3%) 12 (6.1%) 26 (3.9%) 8.8541 0.012
No 258 (98.8%) 197 (94.7%) 185 (93.9%) 640 (96.1%)
NDD
Yes 8 (3.1%) 21 (10.1%) 21 (10.7%) 50 (7.5%) 12.2443 0.002
No 253 (96.9%) 187 (89.9%) 176 (89.3%) 616 (92.5%)
Any Chronic Condition
Yes 65 (24.9%) 94 (45.2%) 84 (42.6%) 243 (36.5%) 25.1301 < 0.001
No 196 (75.1%) 114 (54.8%) 113 (57.4%) 423 (63.5%)
Table 4. Partial versus full vaccination and chronic health conditions
Male
(n=194)
Female
(n=209)
Total
(n=403) Chi-square P-value Odds Ratio
(95% CI)
Allergic rhinitis
Yes 27 (13.9%) 15 (7.2%) 42 (10.4%) 4.8964 0.0269 2.1 (1.1 - 4.1)
No 167 (86.1%) 194 (92.8%) 361 (90.0%)
Allergies
Yes 50 (25.8%) 40 (19.1%) 90 (22.3%) 2.5531 0.1101 1.5 (0.91 - 2.4)
No 144 (74.2%) 168 (80. 9%) 313 (77.7%)
ADHD
Yes 13 (6.7%) 6 (2.9%) 19 (4.7%) 3.2856 0.0699 2.4 (0.90 - 6.5)
No 181 (93.3%) 203 (97.1%) 384 (95.3%)
ASD
Yes 15 (7.7%) 4 (1.9%) 19 (4.7%) 7.5810 0.0059 4.3 (1.4 - 13.2)
No 178 (92.3%) 205 (98.1%) 384 (95.3%)
Eczema
Yes 19 (9.89%) 19 (9.1%) 38 (9.4%) 0.0582 0.8094 1.1 (0.6 - 2.1)
No 175 (90.2%) 190 (90.9%) 365 (90.6%)
Learning Disability
Yes 14 (7.2%) 9 (4.3%) 23 (5.7%) 1.5835 0.2083 1.7 (0.7 - 4.1)
No 180 (92.8%) 200 (95.7%) 380 (94.3%)
NDD
Yes 28 (14.4%) 14 (6.7%) 42 (10.4%) 6.4469 0.0111 2.3 (1.2 - 4.6)
No 166 (85.6%) 195 (93.3%) 361 (89.6%)
Any Chronic Condition
Yes 94 (48.5%) 83 (39.7%) 177 (43.9%) 3.1208 0.0773 1.4 (1.0 - 2.1)
No 100 (51.5%) 126 (60.3%) 226 (56.1%)
Table 5. Chronic conditions and gender among vaccinated children
Factors associated with neurodevelopmental disorders
e second aim of the study focused on a specic health outcome
and was designed to determine whether vaccination was associated
with neurodevelopmental disorders (NDD) and, if so, whether the
association remained signicant aer adjustment for other measured
factors. As noted, because of the relatively small numbers of children
with specic diagnoses, NDD was a derived variable combining
children with a diagnosis of one or more of ASD, ADHD and a learning
disability. e close association and overlap of these diagnoses in the
Mawson AR (2017) Pilot comparative study on the health of vaccinated and unvaccinated 6- to 12-year-old U.S. children
J Transl Sci, 2017 doi: 10.15761/JTS.1000186 Volume 3(3): 7-12
study is shown in the gure above (Figure 1). e gure shows that
the single largest group of diagnoses was learning disability (n=15)
followed by ASD (n=9), and ADHD (n=9), with smaller numbers
comprising combinations of the three diagnoses.
Unadjusted analysis
Table 7 shows that the factors associated with NDD in unadjusted
logistic regression analyses were: vaccination (OR 3.7, 95% CI: 1.7, 7.9);
male gender (OR 2.1, 95% CI: 1.1, 3.8); adverse environment, dened as
living within 1-2 miles of a furniture manufacturing factory, hazardous
waste site, or lumber processing factory (OR 2.9, 95% CI: 1.1, 7.4);
maternal use of antibiotics during pregnancy (OR 2.3, 95% CI: 1.1, 4.8);
and preterm birth (OR 4.9, 95% CI: 2.4, 10.3). Two factors that almost
reached statistical signicance were vaccination during pregnancy
(OR 2.5, 95% CI: 1.0, 6.3) and three or more fetal ultrasounds (OR 3.2,
95% CI: 0.92, 11.5). Factors that were not associated with NDD in this
study included mother’s education, household income, and religious
aliation; use of acetaminophen, alcohol, and antacids during
pregnancy; gestational diabetes; preeclampsia; Rhogham shot during
pregnancy; and breastfeeding (data not shown).
Adjusted analysis
Aer adjustment for all other signicant factors, those that
remained signicantly associated with NDD were: vaccination (OR 3.1,
95% CI: 1.4, 6.8); male gender (OR 2.3, 95% CI: 1.2, 4.3); and preterm
birth (OR 5.0, 95% CI: 2.3, 11.1). e apparently strong association
between both vaccination and preterm birth and NDD suggested the
possibility of an interaction between these factors.
In a nal adjusted model designed to test for this possibility,
controlling for the interaction of preterm birth and vaccination,
the following factors remained signicantly associated with NDD:
vaccination (OR 2.5, 95% CI: 1.1, 5.6), nonwhite race (OR 2.4, 95%
CI: 1.1, 5.4), and male gender (OR 2.3, 95% CI: 1.2, 4.4). Preterm birth
itself, however, was not signicantly associated with NDD, whereas
the combination (interaction) of preterm birth and vaccination was
associated with 6.6-fold increased odds of NDD (95% CI: 2.8, 15.5)
(Table 8).
Discussion
Following a recommendation of the Institute of Medicine [19] for
studies comparing the health outcomes of vaccinated and unvaccinated
Vaccinated (n=405) Unvaccinated (n=261) Total (n=666) Chi-square P-value Odds Ratio (95% CI)
Medication Use
Medication for Allergy
Yes 81 (20.0%) 3 (1.2%) 84 (12.6%) 51.170 < 0.001 21.5 (6.7 - 68.9)
No 324 (80.0%) 258 (98.8%) 582 (87.4%)
Used antibiotics in the past 12 months
Yes 124 (30.8%) 40 (15.4%) 164 (24.7%) 20.092 < 0.001 2.4 (1.6 - 3.6)
No 279 (69.2%) 220 (84.6%) 499 (75.3%)
Used fever medication 1+ times
Yes 350 (90.7%) 173 (67.8%) 523 (81.6%) 53.288 < 0.001 4.6 (3.0 - 7.1)
No 36 (9.3%) 82 (32.2%) 118 (18.4%)
Using tted ear drainage tubes
Yes 12 (3.0%) 1 (0.4%) 13 (2.0%) 5.592 0.018 8.0 (1.0 - 66.1)
No 389 (97.0%) 260 (99.6%) 649 (98.0%)
Used medication for ADHD
Yes 7 (1.7%) 3 (1.2%) 10 (1.5%) 0.346 0.556 -
No 398 (98.3%) 256 (98.8%) 654 (98.5%)
Used medication for Seizures
Yes 4 (1.0%) 1 (0.4%) 5 (0.8%) 0.769 0.653 -
No 400 (99.0%) 258 (99.6%) 658 (99.2)
Health Services Utilization
Emergency Department visit in the past 12
months
Yes 38 (9.5%) 23 (9.0%) 61 (9.3%) 0.047 0.828 -
No 364 (90.5%) 234 (91.0%) 598 (90.7%)
Sick visit to doctor in the past year
Yes 145 (36.0%) 41 (16.0%) 186 (28.2%) 31.096 < 0.001 3.0 (2.0 - 4.4)
No 258 (64.0%) 216 (84.0%) 474 (71.8%)
Ever spent one or more nights in the hospital
Yes 80 (19.8%) 32 (12.3%) 112 (16.8%) 6.267 0.012 1.8 (1.1 - 2.7)
No 325 (80.2%) 228 (87.7%) 553 (83.2%)
Seen doctor for checkup in past 12 months
Yes 233 (57.6%) 97 (37.2%) 330 (49.6%) 26.336 < 0.001 2.3 (1.7 - 3.2)
No 172 (42.4%) 164 (62.8%) 336 (50.4%)
Seen dentist in the past 12 months
Yes 362 (89.4%) 210 (80.5%) 572 (85.9%) 10.424 < 0.001 2.0 (1.3 - 3.2)
No 43 (10.6%) 51 (19.5%) 94 (14.1%)
Table 6. Vaccination status, medication use and health services utilization
Mawson AR (2017) Pilot comparative study on the health of vaccinated and unvaccinated 6- to 12-year-old U.S. children
J Transl Sci, 2017 doi: 10.15761/JTS.1000186 Volume 3(3): 8-12
children, this study focused on homeschool children ages 6 to 12
years based on mothers’ anonymous reports of pregnancy-related
conditions, birth histories, physician-diagnosed illnesses, medications
and healthcare use. Respondents were mostly white, married, and
college-educated, upper income women who had been contacted and
invited to participate in the study by the leaders of their homeschool
organizations. Data from the survey were also used to determine
whether vaccination was associated specically with NDDs, a derived
diagnostic category combining children with the diagnoses of learning
disability, ASD and/or ADHD.
With regard to acute and chronic conditions, vaccinated
children were signicantly less likely than the unvaccinated to have
had chickenpox and pertussis but, contrary to expectation, were
signicantly more likely to have been diagnosed with otitis media,
pneumonia, allergic rhinitis, eczema, and NDD. e vaccinated were
also more likely to have used antibiotics, allergy and fever medications;
to have been tted with ventilation ear tubes; visited a doctor for a
health issue in the previous year, and been hospitalized. e reason for
hospitalization and the age of the child at the time were not determined,
but the latter nding appears consistent with a study of 38,801 reports
to the VAERS of infants who were hospitalized or had died aer
receiving vaccinations. e study reported a linear relationship between
the number of vaccine doses administered at one time and the rate of
hospitalization and death; moreover, the younger the infant at the time
of vaccination, the higher was the rate of hospitalization and death
[55]. e hospitalization rate increased from 11% for 2 vaccine doses
to 23.5% for 8 doses (r2 = 0.91), while the case fatality rate increased
signicantly from 3.6% for those receiving from 1-4 doses to 5.4 % for
those receiving from 5-8 doses.
In support of the possibility that the number of vaccinations
received could be implicated in risks of associated chronic illness, a
NDD
Vaccination Status Ye s
(N=50)
No
(N=616)
Total*
(N=666) Chi-Square P-value OR (95% CI)**
Vaccinated 42 363 405 12.198 <0.001 3.7 (1.7 - 7.9)
Not Vaccinated 8 253 261 Ref
Race
Non-White 9 71 80 1.8208 0.177 1.7 (0.7 - 3.6)
White 41 544 585 Ref
Child's Gender
Male 32 283 315 5.9471 0.015 2.1 (1.1 - 3.8)
Female 18 331 349 Ref
Adverse Environment
Yes 6 27 33
5.8706 0.053
2.9 (1.1 - 7.4)
No 40 523 563 Ref
Do not know 4 66 70 0.8 (0.3 - 2.3)
Medication during
Pregnancy - Antibiotics
Yes 10 61 71 4.950 0.026 2.3 (1.1 - 4.8)
No 40 555 595 Ref
Medication during
Pregnancy –Vaccinated
Yes 6 32 38 3.965 0.057 2.5 (1.0 - 6.3)
No 44 583 627 Ref
Preterm birth
Yes 12 37 49 22.910 < 0.001 4.9 (2.4 - 10.3)
No 38 578 616 Ref
Ultrasound
None 3 71 74 5.898 0.052 Ref
1-3 times 30 419 449 1.7 (0.5 - 5.7)
> 3 times 17 124 141 3.2 (0.92 - 11.5)
*Numbers may not add to column totals due to missing or incomplete data.
**Note that Odds Ratios are the cross-product ratios of the entries in the 2-by-2 tables, and are an estimate of the relative incidence (or risk) of the outcome associated with the
exposure factor.
Table 7. Unadjusted analysis of potential risk factors for neurodevelopmental disorders
Adjusted Model (Model 1) Adjusted Model with Interaction
(Model 2)
Vaccination Status
Vaccinated 3.1 (1.4 - 6.8) 2.5 (1.1 - 5.6)
Not Vaccinated Ref Ref
Race
Non-White 2.3 (1.0 - 5.2) 2.4 (1.1 - 5.4)
White Ref Ref
Child's Gender
Male 2.3 (1.2 - 4.3) 2.3 (1.2 - 4.4)
Female Ref Ref
Preterm birth
NS
Yes 5.0 (2.3 - 11.1)
No Ref
Preterm birth
and Vaccination
interaction
No interaction
Not in the model
Ref
Preterm and
Vaccinated 6.6 (2.8 - 15.5)
*Number of observation read 666, number of observations used 629. NDD=47, Not NDD
= 582
Table 8. Adjusted logistic regression analyses of risk factors and NDD*
Mawson AR (2017) Pilot comparative study on the health of vaccinated and unvaccinated 6- to 12-year-old U.S. children
J Transl Sci, 2017 doi: 10.15761/JTS.1000186 Volume 3(3): 9-12
comparison of unvaccinated, partially and fully vaccinated children in
the present study showed that the partially vaccinated had increased but
intermediate odds of chronic disease, between those of unvaccinated
and fully vaccinated children, specically for allergic rhinitis, ADHD,
eczema, a learning disability, and NDD as a whole.
e national rates of ADHD and LD are comparable to those of
the study. e U.S. rate of ADHD for ages 4-17 (twice the age range of
children than the present study), is 11% [31]. e study rate of ADHD
for ages 6 to 12 is 3.3%, and 4.7% when only vaccinated children are
included. e national LD rate is 5% [32], and the study data show
a rate of LD of 3.9% for all groups, and 5.6% when only vaccinated
children are included. However, the ASD prevalence of 2.24% from a
CDC parent survey is lower than the study rate of 3.3%. Vaccinated
males were signicantly more likely than vaccinated females to have
been diagnosed with allergic rhinitis, and NDD. e percentage of
vaccinated males with an NDD in this study (14.4%) is consistent with
national ndings based on parental responses to survey questions,
indicating that 15% of U.S. children ages 3 to 17 years in the years
2006-2008 had an NDD [28]. Boys are also more likely than girls to be
diagnosed with an NDD, and ASD in particular [29].
Vaccination was strongly associated with both otitis media and
pneumonia, which are among the most common complications of
measles infection [56,57]. e odds of otitis media were almost four-
fold higher among the vaccinated (OR 3.8, 95% CI: 2.1, 6.6) and the
odds of myringotomy with tube placement were eight-fold higher than
those of unvaccinated children (OR 8.0, 95% CI: 1.0, 66.1). Acute otitis
media (AOM) is a very frequent childhood infection, accounting for
up to 30 million physician visits each year in the U.S., and the most
common reason for prescribing antibiotics for children [58,59]. e
incidence of AOM peaks at ages 3 to 18 months and 80% of children
have experienced at least one episode by 3 years of age. Rates of AOM
have increased in recent decades [60]. Worldwide, the incidence of
AOM is 10.9%, with 709 million cases each year, 51% occurring in
children under 5 years of age [61]. Pediatric AOM is a signicant
concern in terms of healthcare utilization in the U.S., accounting for
$2.88 billion in annual health care costs [62].
Numerous reports of AOM have been led with VAERS. A search
of VAERS for “Cases where age is under 1 and onset interval is 0 or
1 or 2 or 3 or 4 or 5 or 6 or 7 days and Symptom is otitis media” [63]
revealed that 438,573 cases were reported between 1990 and 2011,
oen with fever and other signs and symptoms of inammation
and central nervous system involvement. One study [64] assessed
the nasopharyngeal carriage of S. pneumoniae, H. inuenzae, and
M. catarrhalis during AOM in fully immunized, partly immunized
children with 0 or 1 dose of Pneumococcal Conjugate Vaccine-7
(PCV7), and “historical control” children from the pre-PCV-7 era,
and found an increased frequency of M. catarrhalis colonization in
the vaccinated group compared to the partly immunized and control
groups (76% vs. 62% and 56%, respectively). A high rate of Moraxella
catarrhalis colonization is associated with an increased risk of AOM [65].
Successful vaccination against pneumococcal infections can lead to
replacement of the latter in the nasopharyngeal niche by nonvaccine
pneumococcal serotypes and disease [66]. Vaccination with PCV-7 has
a marked eect on the complete microbiota composition of the upper
respiratory tract in children, going beyond shis in the distribution
of pneumococcal serotypes and known potential pathogens and
resulting in increased anaerobes, gram-positive bacteria and gram-
negative bacterial species. PCV-7 administration also correlates highly
with the emergence and expansion of oropharyngeal types of species.
ese observations have suggested that eradication of vaccine serotype
pneumococci can be followed by colonization of other bacterial species
in the vacant nasopharyngeal niche, leading to disequilibria of bacterial
composition (dysbiosis) and increased risks of otitis media. Long-term
monitoring has been recommended as essential for understanding
the full implications of vaccination-induced changes in microbiota
structure [67].
e second aim of the paper focused on a specic health outcome
and sought to determine whether vaccination remained associated
with neurodevelopmental disorders (NDD) aer controlling for
other measured factors. Aer adjustment, the factors that remained
signicantly associated with NDD were vaccination, nonwhite race,
male gender, and preterm birth. e apparently strong association
between both vaccination and preterm birth and NDD suggested the
possibility of an interaction between these factors. is was shown in a
nal adjusted model with interaction (controlling for the interaction of
preterm birth with vaccination). In this model, vaccination, nonwhite
race and male gender remained associated with NDD, whereas preterm
birth itself was no longer associated with NDD. However, preterm birth
combined with vaccination was associated with a 6.6-fold increased
odds of NDD.
In summary, vaccination, nonwhite race, and male gender
were signicantly associated with NDD aer controlling for other
factors. Preterm birth, although signicantly associated with NDD
in unadjusted and adjusted analyses, was no longer associated with
NDD in the nal model with interaction. However, preterm birth and
vaccination combined was strongly associated with NDD in the nal
adjusted model with interaction, more than doubling the odds of NDD
compared to vaccination alone. Preterm birth has long been known as
a major factor for NDD [68,69], but since preterm infants are routinely
vaccinated, the separate eects of preterm birth and vaccination
have not been examined. e present study suggests that vaccination
could be a contributing factor in the pathogenesis of NDD but also
that preterm birth by itself may have a lesser or much reduced role in
NDD (dened here as ASD, ADHD and/or a learning disability) than
currently believed. e ndings also suggest that vaccination coupled
with preterm birth could increase the odds of NDD beyond that of
vaccination alone.
Potential limitations
We did not set out to test a specic hypothesis about the association
between vaccination and health. e aim of the study was to determine
whether the health outcomes of vaccinated children diered from
those of unvaccinated homeschool children, given that vaccines have
nonspecic eects on morbidity and mortality in addition to protecting
against targeted pathogens [11]. Comparisons were based on mothers’
reports of pregnancy-related factors, birth histories, vaccinations,
physician-diagnosed illnesses, medications, and the use of health
services. We tested the null hypothesis of no dierence in outcomes
using chi-square tests, and then used Odds Ratios and 96% Condence
Intervals to determine the strength and signicance of the association.
If the eects of vaccination on health were limited to protection
against the targeted pathogens, as is assumed to be the case [21], no
dierence in outcomes would be expected between the vaccinated and
unvaccinated groups except for reduced rates of the targeted infectious
diseases. However, in this homogeneous sample of 666 children there
were striking dierences in diverse health outcomes between the
groups. e vaccinated were less likely to have had chickenpox or
whooping cough, as expected, but more likely to have been diagnosed
with pneumonia and ear infections as well as allergies and NDDs.
Mawson AR (2017) Pilot comparative study on the health of vaccinated and unvaccinated 6- to 12-year-old U.S. children
J Transl Sci, 2017 doi: 10.15761/JTS.1000186 Volume 3(3): 10-12
What credence can be given to the ndings? is study was not
intended to be based on a representative sample of homeschool
children but on a convenience sample of sucient size to test for
signicant dierences in outcomes. Homeschoolers were targeted for
the study because their vaccination completion rates are lower than those
of children in the general population. In this respect our pilot survey was
successful, since data were available on 261 unvaccinated children.
To eliminate opportunities for subjectivity or opinion in the data,
only factual information was requested and the questions involved
memorable events such as physician-diagnosed diseases in a child.
With regard to minimizing potential bias in the information provided
by mothers, all communications with the latter emphasized neutrality
regarding vaccination and vaccine safety. To minimize recall bias,
respondents were asked to use their child’s vaccination records.
To enhance reliability, closed-ended questions were used and each
set of questions had to be completed before proceeding to the next.
To enhance validity, parents were asked to report only physician-
diagnosed illnesses.
Mothers’ reports could not be validated by clinical records because
the survey was designed to be anonymous. However, self-reports about
signicant events provide a valid proxy for ocial records when medical
records and administrative data are unavailable [70]. Had mothers been
asked to provide copies of their children’s medical records it would
no longer have been an anonymous study and would have resulted
in few completed questionnaires. We were advised by homeschool
leaders that recruitment eorts would have been unsuccessful had we
insisted on obtaining the children’s medical records as a requirement
for participating in the study.
A further potential limitation is under-ascertainment of disease in
unvaccinated children. Could the unvaccinated have articially reduced
rates of illness because they are seen less oen by physicians and would
therefore have been less likely to be diagnosed with a disease? e
vaccinated were indeed more likely to have seen a doctor for a routine
checkup in the past 12 months (57.5% vs. 37.1%, p < 0.001; OR 2.3,
95% CI: 1.7, 3.1). Such visits usually involve vaccinations, which non-
vaccinating families would be expected to refuse. However, fewer visits
to physicians would not necessarily mean that unvaccinated children
are less likely to be seen by a physician if their condition warranted it.
In fact, since unvaccinated children were more likely to be diagnosed
with chickenpox and whooping cough, which would have involved a
visit to the pediatrician, dierences in health outcomes are unlikely to
be due to under-ascertainment.
Strengths of the study include the unique design of the study,
involving homeschool mothers as respondents, and the relatively
large sample of unvaccinated children, which made it possible to
compare health outcomes across the spectrum of vaccination coverage.
Recruitment of biological mothers as respondents also allowed us to
test hypotheses about the role of pregnancy-related factors and birth
history as well as vaccination in NDD and other specic conditions.
In addition, this was a within-group study of a demographically
homogeneous population of mainly white, higher-income and college-
educated homeschooling families in which the children were all 6-12
years of age. Information was provided anonymously by biological
mothers, obviously well-informed about their own children’s vaccination
status and health, which likely increased the validity of the reports.
Conclusions
Assessment of the long-term eects of the vaccination schedule on
morbidity and mortality has been limited [71]. In this pilot study of
vaccinated and unvaccinated homeschool children, reduced odds of
chickenpox and whooping cough were found among the vaccinated,
as expected, but unexpectedly increased odds were found for many
other physician-diagnosed conditions. Although the cross-sectional
design of the study limits causal interpretation, the strength and
consistency of the ndings, the apparent “dose-response” relationship
between vaccination status and several forms of chronic illness, and
the signicant association between vaccination and NDDs all support
the possibility that some aspect of the current vaccination program
could be contributing to risks of childhood morbidity. Vaccination
also remained signicantly associated with NDD aer controlling for
other factors, whereas preterm birth, long considered a major risk
factor for NDD, was not associated with NDD aer controlling for
the interaction between preterm birth and vaccination. In addition,
preterm birth coupled with vaccination was associated with an apparent
synergistic increase in the odds of NDD above that of vaccination
alone. Nevertheless, the study ndings should be interpreted with
caution. First, additional research is needed to replicate the ndings
in studies with larger samples and stronger research designs. Second,
subject to replication, potentially detrimental factors associated with
the vaccination schedule should be identied and addressed and
underlying mechanisms better understood. Such studies are essential
in order to optimize the impact of vaccination of children’s health.
Competing Interests
e authors declare that they have no nancial interests that had
any bearing on any aspect of the conduct or conclusions of the study
and the submitted manuscript.
Author contributions
AM designed the study, contributed to data analysis and
interpretation, and draed the paper. BR designed the study,
contributed to data collection, and edited the paper. AB contributed to
data analyses and edited the paper. BJ contributed to data analyses and
editing. All authors read and approved the nal version of the paper.
Funding sources
is study was supported by grants from Generation Rescue,
Inc., and the Children’s Medical Safety Research Institute, charitable
organizations that support research on children’s health and safety.
e funders had no role or inuence on the design and conduct of the
research or the preparation of reports.
Acknowledgments
e authors thank all those who contributed critical comments,
suggestions and nancial support for the project. We also thank the
collaborating homeschool organizations and especially the mothers
who participated in the survey.
Disclaimer
is study was approved by the Institutional Review Board of
Jackson State University and completed prior to Dr. Mawson’s tenure-
track appointment at Jackson State University.
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... Previous studies such as the Mawson study (2017) [9] reported high odds ratios for allergic rhinitis (30.1), learning disabilities (5.2), ADHD (4.2), autism (4.2), neurodevelopmental disorders (3.7), eczema (2.9), and chronic illness (2.4) but were limited because they were based on survey data. While not necessarily fatal to a study, the highly charged nature of the vaccine risk research brings a special concern over survey respondents who might, for the sake of advocacy, seek or unintentionally emphasize their unvaccinated child's lack of diagnoses or amplify their vaccinated child's larger number of diagnoses. ...
... While not necessarily fatal to a study, the highly charged nature of the vaccine risk research brings a special concern over survey respondents who might, for the sake of advocacy, seek or unintentionally emphasize their unvaccinated child's lack of diagnoses or amplify their vaccinated child's larger number of diagnoses. Recall bias is a potential factor in this setting, and therefore, our results go a long way to validate those on the Mawson (2017) [9] study. The age range in that study was also restricted to 6-to 12-year-olds, precluding the comparison of the cumulative rates from day 1 of life. ...
... We concur with Mawson et al., 2017 [9], who reported: "Further research involving larger, independent samples is needed to verify and understand these unexpected findings in order to optimize the impact of vaccines on children's health. " We also concur with Hooker and Miller 2020 [14], who wrote: "Further study is necessary to understand the full spectrum of health effects associated with childhood vaccination". ...
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We performed a retrospective analysis spanning ten years of pediatric practice focused on patients with variable vaccination born into a practice, presenting a unique opportunity to study the effects of variable vaccination on outcomes. The average total incidence of billed office visits per outcome related to the outcomes were compared across groups (Relative Incidence of Office Visit (RIOV)). RIOV is shown to be more powerful than odds ratio of diagnoses. Full cohort, cumulative incidence analyses, matched for days of care, and matched for family history analyses were conducted across quantiles of vaccine uptake. Increased office visits related to many diagnoses were robust to days-of-care-matched analyses, family history, gender block, age block, and false discovery risk. Many outcomes had high RIOV odds ratios after matching for days-of-care (e.g., anemia (6.334), asthma (3.496), allergic rhinitis (6.479), and sinusitis (3.529), all significant under the Z-test). Developmental disorders were determined to be difficult to study due to extremely low prevalence in the practice, potentially attributable to high rates of vaccine cessation upon adverse events and family history of autoimmunity. Remarkably, zero of the 561 unvaccinated patients in the study had attention deficit hyperactivity disorder (ADHD) compared to 0.063% of the (partially and fully) vaccinated. The implications of these results for the net public health effects of whole-population vaccination and with respect for informed consent on human health are compelling. Our results give agency to calls for research conducted by individuals who are independent of any funding sources related to the vaccine industry. While the low rates of developmental disorders prevented sufficiently powered hypothesis testing, it is notable that the overall rate of autism spectrum disorder (0.84%) in the cohort is half that of the US national rate (1.69%). The practice-wide rate of ADHD was roughly half of the national rate. The data indicate that unvaccinated children in the practice are not unhealthier than the vaccinated and indeed the overall results may indicate that the unvaccinated pediatric patients in this practice are healthier overall than the vaccinated.
... That same year, the U.S. Department of Health and Human Services funded a health survey that estimated 54% of U.S. children have at least 1 of 22 chronic health conditions [3], up from 12.8% in 1994 [4]. Although the causes of these persistent health ailments are undoubtedly multifaceted, some studies have found significant relationships between vaccines and many of these conditions, including allergies [5,6], asthma [6,7], attention deficit disorder (ADD/ ADHD) [5,[8][9][10], autism [5,[11][12][13], ear infections [5,14,15], seizures [16][17][18], developmental delay [5,9,19], diabetes [20][21][22], and more. ...
... That same year, the U.S. Department of Health and Human Services funded a health survey that estimated 54% of U.S. children have at least 1 of 22 chronic health conditions [3], up from 12.8% in 1994 [4]. Although the causes of these persistent health ailments are undoubtedly multifaceted, some studies have found significant relationships between vaccines and many of these conditions, including allergies [5,6], asthma [6,7], attention deficit disorder (ADD/ ADHD) [5,[8][9][10], autism [5,[11][12][13], ear infections [5,14,15], seizures [16][17][18], developmental delay [5,9,19], diabetes [20][21][22], and more. ...
... That same year, the U.S. Department of Health and Human Services funded a health survey that estimated 54% of U.S. children have at least 1 of 22 chronic health conditions [3], up from 12.8% in 1994 [4]. Although the causes of these persistent health ailments are undoubtedly multifaceted, some studies have found significant relationships between vaccines and many of these conditions, including allergies [5,6], asthma [6,7], attention deficit disorder (ADD/ ADHD) [5,[8][9][10], autism [5,[11][12][13], ear infections [5,14,15], seizures [16][17][18], developmental delay [5,9,19], diabetes [20][21][22], and more. ...
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Using survey data from respondents associated with three medical practices in the US, vaccinated children were compared to unvaccinated children for the incidence of severe allergies, autism, gastrointestinal disorders, asthma, ADHD, and chronic ear infections. All diagnoses were based on parental reporting with chart review for confirmation of diagnoses. Cases were stratified with non-cases based on year of birth and sex, and compared using a logistic regression model which also accounted for breastfeeding status and type of birth (vaginal versus cesarean section). Vaccinated children were significantly more likely than unvaccinated children to be diagnosed with severe allergies (OR = 4.31, 95% CI 1.67 - 11.1), autism (OR = 5.03, 95% CI 1.64 - 15.5), gastrointestinal disorders (OR = 13.8, 95% CI 5.85 - 32.5), asthma (OR = 17.6, 95% CI 6.94 - 44.4), ADHD (OR = 20.8, 95% CI 4.74 - 91.2), and chronic ear infections (OR = 27.8, 95% CI 9.56 - 80.8). Vaccinated children were less likely to be diagnosed with chickenpox (OR = 0.10, 95% CI 0.029 - 0.36). Children who were "vaccinated and not breastfed" or "vaccinated and delivered via cesarean section" had the highest rates of adverse health outcomes. In this study, higher ORs were observed within the vaccinated versus unvaccinated groups for several adverse health conditions. Further research is essential to understand the full scope of health effects associated with childhood vaccination.
... whole are largely unknown. 3 For instance, Kuter et al. 4 detailed 23 different post-licensing trials conducted on the measles, mumps and rubella (MMR)-II vaccine and in no instance were the patients followed for more than 42 days post-vaccination. In 2011, the Institute of Medicine (IOM) 5 published the report "Adverse Effects of Vaccines: Evidence and Causality" where the relationships between specific vaccines and different adverse health effects were considered. ...
... One study, published by Mawson et al., 3 was based on a convenience sample of homeschooled children where a significant portion of the sample (39%) was unvaccinated. In this small sample, vaccinated children showed higher odds of being diagnosed with pneumonia, otitis media, allergies and neurodevelopmental disorders. ...
... 18 The IOM 19 Immunization Safety Review Committee conducted an evaluation regarding thimerosal-containing vaccines and concluded that "the hypothesis that exposure to thimerosal-containing vaccines could be associated with neurodevelopment disorders" was biologically plausible. Mawson et al. 3 found a relationship between vaccination status and learning disability and neurodevelopmental disorders. Delong 20 also reported a significant relationship to neurodevelopmental disorders (autism and speech and language delay) when looking at the proportions of vaccine uptake in US children. ...
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Objective The aim of this study was to compare the health of vaccinated versus unvaccinated pediatric populations. Methods Using data from three medical practices in the United States with children born between November 2005 and June 2015, vaccinated children were compared to unvaccinated children during the first year of life for later incidence of developmental delays, asthma, ear infections and gastrointestinal disorders. All diagnoses utilized International Classification of Diseases–9 and International Classification of Diseases–10 codes through medical chart review. Subjects were a minimum of 3 years of age, stratified based on medical practice, year of birth and gender and compared using a logistic regression model. Results Vaccination before 1 year of age was associated with increased odds of developmental delays (OR = 2.18, 95% CI 1.47–3.24), asthma (OR = 4.49, 95% CI 2.04–9.88) and ear infections (OR = 2.13, 95% CI 1.63–2.78). In a quartile analysis, subjects were grouped by number of vaccine doses received in the first year of life. Higher odds ratios were observed in Quartiles 3 and 4 (where more vaccine doses were received) for all four health conditions considered, as compared to Quartile 1. In a temporal analysis, developmental delays showed a linear increase as the age cut-offs increased from 6 to 12 to 18 to 24 months of age (ORs = 1.95, 2.18, 2.92 and 3.51, respectively). Slightly higher ORs were also observed for all four health conditions when time permitted for a diagnosis was extended from ⩾ 3 years of age to ⩾ 5 years of age. Conclusion In this study, which only allowed for the calculation of unadjusted observational associations, higher ORs were observed within the vaccinated versus unvaccinated group for developmental delays, asthma and ear infections. Further study is necessary to understand the full spectrum of health effects associated with childhood vaccination.
... Some public health experts claim that there have been up to 103 million prevented cases of contagious diseases since 1924 as a result of vaccines [57]. Despite the documented successes of the practice, there are still some in the medical community who have concerns about the risks or side effects of vaccines, and question the practice of mandatory vaccination [58]. The most infamous example of this is in a 1998 article published in The Lancet (now redacted) by Andrew Wakefield that reported a connection between the measles, mumps, and rubella vaccine and developmental disorders in children [59]. ...
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Nowadays, many people are deeply concerned about their physical well-being; as a result, they invest much time and effort investigating health-related topics. In response to this, many online websites and social media profiles have been created, resulting in a plethora of information on such topics. In a given topic, oftentimes, much of the information is conflicting, resulting in online camps that have different positions and arguments. We refer to the collection of all such positionings and entrenched camps on a topic such as an online public health debate. The information people encounter regarding such debates can ultimately influence how they make decisions, what they believe, and how they act. Therefore, there is a need for public health stakeholders (i.e., people with a vested interest in public health issues) to be able to make sense of online debates quickly and accurately. In this paper, we present a framework-based approach for investigating online public health debates—a preliminary work that can be expanded upon. We first introduce the concept of online debate entities (ODEs), which is a generalization for those who participate in online debates (e.g., websites and Twitter profiles). We then present the framework ODIN (Online Debate entIty aNalyzer), in which we identify, define, and justify ODE attributes that we consider important for making sense of online debates. Next, we provide an overview of four online public health debates (vaccines, statins, cannabis, and dieting plans) using ODIN. Finally, we showcase four prototype visual analytics systems whose design elements are informed by the ODIN framework.
... In the face of this uncertainty, the first author and colleagues studied vaccinated and unvaccinated homeschooled children, among whom vaccination coverage rates are lower than in the general population [31,32]. The aims were to compare health outcomes and exposures to determine if any association found between vaccination and NDDs remained significant after controlling for other significant factors. ...
Article
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A growing number of vaccines are administered at the same time or in close succession, increasing the complexity of assessing vaccine safety. Individual vaccines are assumed to have no other effect than protection against the targeted pathogen, but vaccines also have nonspecific and interactive effects, the outcomes of which can be beneficial or harmful. To date, no controlled trials and very few observational studies have determined the impact of vaccination schedules on overall health. The balance of the risks and benefits from mass vaccination therefore remains uncertain. Recent studies worryingly suggest links between multiple vaccinations and increased risks of diverse multisystem health problems, including allergies, infections, and neuropsychiatric or neurodevelopmental disorders. Here, we propose that, in susceptible persons, multiple vaccinations activate the retinoid cascade and trigger apoptotic hepatitis, leading to cholestatic liver dysfunction, in which stored vitamin A compounds (retinyl esters and retinoic acid) enter the circulation in toxic concentrations; this induces endogenous forms of hypervitaminosis A, with the severity of adverse outcomes being directly proportional to the concentration of circulating retinoids. In very low concentrations, vitamin A and its major metabolite retinoic acid contribute to immune function and to the process of immunization, whereas excess vitamin A increases the risk of adverse events, including common “side-effects” as well as chronic adverse outcomes. The increasing rates of allergy, ear infections, and neurodevelopmental disorders (NDDs) in countries with high rates of vaccination could be related to mass vaccination and to its impact on liver function and vitamin A metabolism, collectively representing endogenous manifestations of hypervitaminosis A. Further studies of health outcomes in vaccinated and unvaccinated groups are urgently needed, to increase understanding of the pathophysiology and treatment of vaccine injury, to identify the risk factors and screen for vaccine injury, to inform public health policy on potential hazards related to vaccination schedules, and to optimize the safety and benefits of vaccines.
... In line with this, several recent studies suggested a potential beneficial effect of influenza vaccination 68 on susceptibility to COVID-19 [12,13]. Despite earlier reports that have shown little or opposite effects 69 of influenza vaccines on heterologous infections in children [14][15][16][17][18][19]. With the flu season on its way and 70 influenza vaccination campaigns starting off soon, it is paramount to clarify the exact effects of influenza 71 vaccination on the incidence and the disease course of COVID- 19. ...
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Every year, influenza causes 290.000 to 650.000 deaths worldwide and vaccination is encouraged to prevent infection in high-risk individuals. Interestingly, cross-protective effects of vaccination against heterologous infections have been reported, and long-term boosting of innate immunity (also termed trained immunity ) has been proposed as the underlying mechanism. Several epidemiological studies also suggested cross-protection between influenza vaccination and COVID-19 during the current pandemic. However, the mechanism behind such an effect is unknown. Using an established in-vitro model of trained immunity, we demonstrate that the quadrivalent inactivated influenza vaccine used in the Netherlands in the 2019-2020 influenza season can induce a trained immunity response, including an improvement of cytokine responses after stimulation of human immune cells with SARS-CoV-2. In addition, we found that SARS-CoV-2 infection was less common among Dutch hospital employees who had received influenza vaccination during the 2019/2020 winter season (RR = 0,61 (95% CI, 0.4585 - 0.8195, P = 0.001). In conclusion, a quadrivalent inactivated influenza vaccine can induce trained immunity responses against SARS-CoV-2, which may result in relative protection against COVID-19. These data, coupled with similar recent independent reports, argue for a beneficial effect of influenza vaccination against influenza as well as COVID-19, and suggests its effective deployment in the 2020-2021 influenza season to protect against both infections.
... We have shown that Pasteur's theory of "infectious" disease is erroneous. Pasteur's other legacy, vaccines, carry both short-term and long-term health risks and will become irrelevant with the availability of QSI supplements [29]. ...
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Pasteur's theory of infection is a cornerstone of Western medicine. Here we propose a new approach that the proliferation of microorganisms in infectious diseases is encouraged by chronic stress-induced imbalances in the host that suppress both the immune and the digestive systems. Nature's method of controlling microbial growth uses quorum sensing inhibition, which disrupts the essential molecular signaling between microorganisms. Signal molecules produced by bacteria allow the pathogens to coordinate their behavior, and after reaching a threshold level, stimulates them to activate their virulence genes. However, the resulting infectious disease can be interrupted and even prevented by suitable, mainly hydrophobic quorum sensing inhibitor molecules present in a variety of common foods and spices. When a host's metabolic reservoir is enriched with these plant-derived inhibitors, infectious disease cannot develop-even if pathogenic microorganisms are present. In addition, these same bacterial inhibitors are also potent immune stimulants which can help reverse immune suppression. Microbes are not solely causative in the disease process, but merely opportunistic parasitic organisms, whose proliferation can be suppressed by resupplying the body with the necessary quorum sensing inhibitory nutrients. This observation challenges Pasteur's theory, and provides a straightforward alternative to Western medicine's antibiotic and antiviral-based microbial control methods, while also questioning the rationale for vaccination.
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Aim To test the internal validity of the test-negative design (TND) by investigating associations between maternal influenza vaccination, and new virus detection episodes (VDEs), acute respiratory illness, and healthcare visits in their children. Methods Eighty-five children from a birth cohort provided daily symptoms, weekly nasal swabs, and healthcare use data until age 2-years. Effect estimates are summarised as incidence rate ratios (IRR). Results There was no association between maternal vaccination and VDEs in children (IRR = 1.1; 95 %CI = 0.9–1.2). Influenza-vaccinated mothers were more likely than unvaccinated mothers to both report, and seek healthcare for, acute lower respiratory illness in their children, IRR = 2.4; 95 %CI = 1.2–4.8 and IRR = 2.2; 95 %CI = 1.1–4.3, respectively. Conclusion A key assumption of the TND, that healthcare seeking behaviour for conditions of the same severity is not associated with vaccine receipt, did not hold. Further studies of the performance of the TND in different populations are required to confirm its validity.
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Täglich werden Kinderärzte mit den Sorgen impfskeptischer Eltern konfrontiert. Einige haben Vorbehalte, andere lehnen Impfungen rundweg ab. Wappnen Sie sich gegen verzerrte Fakten und Falschinformationen aus dem Internet. Diese Argumente überzeugen.
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Preterm infants face an increased risk of autism spectrum disorder (ASD). The relationship between autism during childhood and early brain development remains unexplored. We studied 84 preterm children born at <27 weeks of gestation, who underwent neonatal magnetic resonance imaging (MRI) at term and were screened for ASD at 6.5 years. Full-scale intelligence quotient was measured and neonatal morbidities were recorded. Structural brain morphometric studies were performed in 33 infants with high-quality MRI and no evidence of focal brain lesions. Twenty-three (27.4%) of the children tested ASD positive and 61 (72.6%) tested ASD negative. The ASD-positive group had a significantly higher frequency of neonatal complications than the ASD-negative group. In the subgroup of 33 children, the ASD infants had reduced volumes in the temporal, occipital, insular, and limbic regions and in the brain areas involved in social/behavior and salience integration. This study shows that the neonatal MRI scans of extremely preterm children, subsequently diagnosed with ASD at 6.5 years, showed brain structural alterations, localized in the regions that play a key role in the core features of autism. Early detection of these structural alterations may allow the early identification and intervention of children at risk of ASD.
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Epidemiological observations have shown that vaccines can influence morbidity and mortality more than can be ascribed to target-disease immunity. A growing number of immunological studies have helped identify possible biological mechanisms to explain these so-called nonspecific effects (NSE) of vaccines, including heterologous T-cell reactivity and innate immune memory or ‘trained innate immunity’, which involves epigenetic reprogramming of innate immune cells. Here, we review the epidemiological evidence for NSE as well as human, animal and in vitro immunological data that could explain these NSE, and discuss priorities for future epidemiologic and immunologic studies to further unravel the biology and optimize the benefits of current and new vaccines.
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The developmental disabilities questions in the 2014 National Health Interview Survey (NHIS) were changed from previous years, including question reordering and a new approach to asking about autism spectrum disorder (ASD). This report examines survey-based estimates of the lifetime prevalence of ASD, intellectual disability (ID), and any other developmental delay (other DD) following the inclusion of a standalone ASD question, the inclusion of specific diagnoses in the ASD question, and the ASD question preceding the other DD question, and compares them with estimates from previous years.
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Description of System: The Autism and Developmental Disabilities Monitoring (ADDM) Network is an active surveillance system in the United States that provides estimates of the prevalence of ASD and other characteristics among children aged 8 years whose parents or guardians live in 11 ADDM sites in the United States. ADDM surveillance is conducted in two phases. The first phase consists of screening and abstracting comprehensive evaluations performed by professional providers in the community. Multiple data sources for these evaluations include general pediatric health clinics and specialized programs for children with developmental disabilities. In addition, most ADDM Network sites also review and abstract records of children receiving specialeducation services in public schools. The second phase involves review of all abstracted evaluations by trained clinicians to determine ASD surveillance case status. A child meets the surveillance case definition for ASD if a comprehensive evaluation of that child completed by a qualified professional describes behaviors consistent with the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) diagnostic criteria for any of the following conditions: autistic disorder, pervasive developmental disorder-not otherwise specified (including atypical autism), or Asperger disorder. This report provides updated prevalence estimates for ASD from the 2010 surveillance year. In addition to prevalence estimates, characteristics of the population of children with ASD are described. Results: For 2010, the overall prevalence of ASD among the ADDM sites was 14.7 per 1,000 (one in 68) children aged 8 years. Overall ASD prevalence estimates varied among sites from 5.7 to 21.9 per 1,000 children aged 8 years. ASD prevalence estimates also varied by sex and racial/ethnic group. Approximately one in 42 boys and one in 189 girls living in the ADDM Network communities were identified as having ASD. Non-Hispanic white children were approximately 30% more likely to be identified with ASD than non-Hispanic black children and were almost 50% more likely to be identified with ASD than Hispanic children. Among the seven sites with sufficient data on intellectual ability, 31% of children with ASD were classified as having IQ scores in the range of intellectual disability (IQ ≤70), 23% in the borderline range (IQ = 71-85), and 46% in the average or above average range of intellectual ability (IQ > 85). The proportion of children classified in the range of intellectual disability differed by race/ethnicity. Approximately 48% of non-Hispanic black children with ASD were classified in the range of intellectual disability compared with 38% of Hispanic children and 25% of non-Hispanic white children. The median age of earliest known ASD diagnosis was 53 months and did not differ significantly by sex or race/ethnicity. Interpretation: These findings from CDC's ADDM Network, which are based on 2010 data reported from 11 sites, provide updated population-based estimates of the prevalence of ASD in multiple communities in the United States. Because the ADDM Network sites do not provide a representative sample of the entire United States, the combined prevalence estimates presented in this report cannot be generalized to all children aged 8 years in the United States population. Consistent with previous reports from the ADDM Network, findings from the 2010 surveillance year were marked by significant variations in ASD prevalence by geographic area, sex, race/ethnicity, and level of intellectual ability. The extent to which this variation might be attributable to diagnostic practices, underrecognition of ASD symptoms in some racial/ethnic groups, socioeconomic disparities in access to services, and regional differences in clinical or school-based practices that might influence the findings in this report is unclear. Public Health Action: ADDM Network investigators will continue to monitor the prevalence of ASD in select communities, with a focus on exploring changes within these communities that might affect both the observed prevalence of ASD and population-based characteristics of children identified with ASD. Although ASD is sometimes diagnosed by 2 years of age, the median age of the first ASD diagnosis remains older than age 4 years in the ADDM Network communities. Recommendations from the ADDM Network include enhancing strategies to address the need for 1) standardized, widely adopted measures to document ASD severity and functional limitations associated with ASD diagnosis; 2) improved recognition and documentation of symptoms of ASD, particularly among both boys and girls, children without intellectual disability, and children in all racial/ethnic groups; and 3) decreasing the age when children receive their first evaluation for and a diagnosis of ASD and are enrolled in community-based support systems.
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Tightening the rules for non-medical exemptions is not justified and will increase parental mistrust and resistance, argues Allan S Cunningham Since my medical career began in 1962 I have seen the harmful effects of nearly all of the vaccine preventable diseases on the US immunization schedule. I have enthusiastically administered many thousands of vaccine doses and am glad that my children and grandchildren are well vaccinated. However, the current attitudes of public health officials about vaccine mandates and exemptions are arrogant and patronizing. In the US all 50 states and the District of Columbia require children and adolescents to be vaccinated before they attend school, college, or preschool programs.1 Rhode Island has the most extensive requirements, including mandates for vaccination against hepatitis A and B, Haemophilus influenzae type B, rotavirus, human papillomavirus, and influenza.2 Medical exemptions are granted in all jurisdictions, and religious exemptions are granted everywhere but Mississippi and West Virginia. Only 20 states grant personal exemptions. The recent US measles outbreak has given rise to a lot of media hyperventilation about vaccine exemptions. There have been calls for outright bans …
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Autism spectrum disorder (ASD) is common, life-long in nature, and can be very debilitating. Thus, an intensive search is on to identify the potential risk factors for the disorder. Premature birth has been identified as one potential factor that could influence potential symptoms of ASD. The sample for this study consisted of 1655 at risk children for developmental delays who were 17-37 months of age. Participants were divided into those diagnosed with ASD (n = 916) and children with atypical development only (n = 739). Premature births were almost twice as common for the atypical development group versus the ASD group. Implications of these data are discussed.
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Despite research showing no link between the measles-mumps-rubella (MMR) vaccine and autism spectrum disorders (ASD), beliefs that the vaccine causes autism persist, leading to lower vaccination levels. Parents who already have a child with ASD may be especially wary of vaccinations. To report ASD occurrence by MMR vaccine status in a large sample of US children who have older siblings with and without ASD. A retrospective cohort study using an administrative claims database associated with a large commercial health plan. Participants included children continuously enrolled in the health plan from birth to at least 5 years of age during 2001-2012 who also had an older sibling continuously enrolled for at least 6 months between 1997 and 2012. MMR vaccine receipt (0, 1, 2 doses) between birth and 5 years of age. ASD status defined as 2 claims with a diagnosis code in any position for autistic disorder or other specified pervasive developmental disorder (PDD) including Asperger syndrome, or unspecified PDD (International Classification of Diseases, Ninth Revision, Clinical Modification 299.0x, 299.8x, 299.9x). Of 95 727 children with older siblings, 994 (1.04%) were diagnosed with ASD and 1929 (2.01%) had an older sibling with ASD. Of those with older siblings with ASD, 134 (6.9%) had ASD, vs 860 (0.9%) children with unaffected siblings (P < .001). MMR vaccination rates (≥1 dose) were 84% (n = 78 564) at age 2 years and 92% (n = 86 063) at age 5 years for children with unaffected older siblings, vs 73% (n = 1409) at age 2 years and 86% (n = 1660) at age 5 years for children with affected siblings. MMR vaccine receipt was not associated with an increased risk of ASD at any age. For children with older siblings with ASD, at age 2, the adjusted relative risk (RR) of ASD for 1 dose of MMR vaccine vs no vaccine was 0.76 (95% CI, 0.49-1.18; P = .22), and at age 5, the RR of ASD for 2 doses compared with no vaccine was 0.56 (95% CI, 0.31-1.01; P = .052). For children whose older siblings did not have ASD, at age 2, the adjusted RR of ASD for 1 dose was 0.91 (95% CI, 0.67-1.20; P = .50) and at age 5, the RR of ASD for 2 doses was 1.12 (95% CI, 0.78-1.59; P = .55). In this large sample of privately insured children with older siblings, receipt of the MMR vaccine was not associated with increased risk of ASD, regardless of whether older siblings had ASD. These findings indicate no harmful association between MMR vaccine receipt and ASD even among children already at higher risk for ASD.
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Controversy about the evidence, economics, ethics, lobbying, and decision making surrounding a new vaccine for serogroup B meningococcal disease should trigger change in the way we develop recommendations for new vaccines say Natasha Crowcroft and colleagues