Barbara Watson

Publications (20)79.41 Total impact

• Article: Varicella in infants after implementation of the US varicella vaccination program.

  Sandra S Chaves, Adriana S Lopez, Tureka L Watson, Rachel Civen, Barbara Watson, Laurene Mascola, Jane F Seward
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  ABSTRACT: To describe varicella disease in infants since implementation of the varicella vaccination program in the United States. From 1995 to 2008, demographic, clinical, and epidemiologic data on cases of varicella in infants were collected prospectively through a community-based active surveillance project. We examined disease patterns for infants in 2 age groups: 0 to 5 and 6 to 11 months. Infant varicella disease incidence declined 89.7% from 1995 to 2008. Infants aged 0 to 5 months had milder clinical disease than those aged 6 to 11 months: ≥50 lesions, 49% vs 58% (P = .038); fever (body temperature > 38°C), 12% vs 21% (P = .014); and varicella-related complications, 6% vs 14% (P = .009), respectively. Age was an independent predictor of the occurrence of complications. The varicella vaccination program has resulted in substantial indirect benefits for infants, who are not eligible for vaccination. Presence of maternal varicella-zoster virus antibodies might explain attenuated disease in very young infants likely born to mothers with history of varicella. Although varicella disease incidence has declined, exposure to varicella-zoster virus continues to occur. Improving varicella vaccination coverage in all age groups will further reduce the risk of varicella exposure and protect those not eligible for varicella vaccination.
  PEDIATRICS 12/2011; 128(6):1071-7. · 4.47 Impact Factor
• Article: Incremental effectiveness of second dose varicella vaccination for outbreak control at an elementary school in Philadelphia, pennsylvania, 2006.

  Michael D Nguyen, Dana Perella, Barbara Watson, Mona Marin, Mia Renwick, C Victor Spain
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  ABSTRACT: In 2006, the Philadelphia Department of Public Health conducted an investigation of a varicella outbreak at an elementary school in which second-dose vaccination for outbreak control (VOC) was implemented. We evaluated the effectiveness of this intervention. Self-administered questionnaires collected varicella disease and vaccination information. Students eligible for second-dose VOC were 1-dose vaccine recipients without prior varicella disease. A breakthrough varicella case was defined as a maculopapulovesicular rash in a student with onset >42 days after 1-dose vaccination without other apparent cause. Vaccine effectiveness was evaluated using survival analysis techniques and analyzed by vaccine status (first dose versus second dose). Multivariable Cox proportional hazard models were used to identify statistical interactions and adjust for confounders. The questionnaire response rate was 92% (342/370). Of the 286 eligible students, 187 (65%) received a second-dose VOC. The crude attack rate was 9/187 (5%) among second-dose VOC recipients; 43/99 (43%) among 1-dose recipients, and 5/6 (83%) among unvaccinated students. Second-dose VOC recipients had milder rashes, compared with 1-dose or unvaccinated students. The adjusted incremental second-dose vaccine effectiveness was 76% (95% confidence interval: 44%-90%) for students with classroom exposure. Incremental effectiveness was similar (79%) when we extended the immune response time from 4 days to 7 days after second-dose VOC. Second-dose VOC resulted in a substantial reduction in varicella incidence for students with classroom exposure. Until high rates of routine second-dose vaccine coverage are achieved, clinicians should consider second-dose VOC an appropriate intervention to reduce disease transmission in institution-based outbreaks.
  The Pediatric Infectious Disease Journal 03/2010; 29(8):685-9. · 3.58 Impact Factor
• Article: Validity of reported varicella history as a marker for varicella zoster virus immunity among unvaccinated children, adolescents, and young adults in the post-vaccine licensure era.

  Dana Perella, Alexander G Fiks, Aisha Jumaan, Donovan Robinson, Paul Gargiullo, Jonathan Pletcher, Christine M Forke, D Scott Schmid, Mia Renwick, Foram Mankodi, Barbara Watson, C Victor Spain
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  ABSTRACT: We assessed the validity of reported varicella history as a marker for varicella zoster virus immunity among unvaccinated persons 1 to 29 years of age, and we examined varicella disease characteristics associated with varicella zoster virus immunity among those reporting positive histories. We conducted a cross-sectional study at 7 community-based sites in Philadelphia, Pennsylvania, between June 2004 and May 2006 and recruited 1476 participants 1 to 29 years of age who had not been vaccinated against varicella. Sensitivity, specificity, and positive predictive value were determined by comparing self-reported or parent-reported varicella histories from a standardized study interview with varicella zoster virus immunoglobulin G serological results for each participant. We performed multivariate logistic regression analyses to determine which disease characteristics best predicted seropositivity. The sensitivity of reported varicella history was highest (81%-89%) among participants > or =10 years of age, whereas specificity was highest among participants 1 to 4 years of age (99%) and > or =20 years (88%). Reported varicella history was highly predictive of seropositivity (>95%) only among participants > or =15 years of age. For participants 10 to 14 years of age, parental reports of a generalized itchy rash with 1 of the following were highly predictive of seropositivity: varicella transmission to another household member or being raised in a household with no other children. Among participants < or =9 years of age, no combination of disease characteristics was both highly predictive of seropositivity and common. The validity of reported varicella history varies according to age, and a reported history is no longer highly predictive of seropositivity among cohorts born since 1994 (participants < or =9 years of age). Universal varicella vaccination, regardless of history, for these children should be considered, as should simplified criteria for varicella zoster virus immunity among unvaccinated persons born before 1994.
  PEDIATRICS 05/2009; 123(5):e820-8. · 4.47 Impact Factor
• Article: New Advisory Committee on Immunization Practices guidelines for rotavirus vaccine allow more children to receive vaccine.

  Irini Daskalaki, Sarah S Long, Barbara Watson, Lance Chilton
  PEDIATRICS 02/2009; 123(1):e174-5. · 4.47 Impact Factor
• Article: Implementation of rotavirus immunization in Philadelphia, Pennsylvania: high levels of vaccine ineligibility and off-label use.

  Irini Daskalaki, C Victor Spain, Sarah S Long, Barbara Watson
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  ABSTRACT: Our goal was to predict, using delayed diphtheria-tetanus-acellular pertussis vaccination as an indicator, whether the current narrowly defined age limits for pentavalent rotavirus vaccine exclude a substantial proportion of children from complete immunization against rotavirus and to assess adherence of providers to recommended age limits by examining the first 6 months of use of pentavalent rotavirus vaccine in Philadelphia, Pennsylvania. Data from a computerized children's immunization registry in Philadelphia were analyzed. Demographics and age at immunization with first 3 diphtheria-tetanus-acellular pertussis doses were examined from 2001 to 2005. Similar characteristics were evaluated for children who received pentavalent rotavirus vaccine doses during the first 6 months of its availability (August 2006 through January 2007). During the 5-year period, 24 403 of 103 967 recipients of first diphtheria-tetanus-acellular pertussis vaccine were >12 weeks of age; only 56 411 of 79 564 first diphtheria-tetanus-acellular pertussis recipients <or=12 weeks of age received the first 3 doses at ages that they could have completed the pentavalent rotavirus vaccine series if vaccines were given at the same visit. Children using public providers were more likely to have delayed immunization. During the first 6 months of pentavalent rotavirus vaccine implementation, 5566 pentavalent rotavirus vaccine doses were recorded in the Kids Immunization Database/Tracking System: 3912 first doses, 1419 second doses, and 235 third doses. Of 3912 first-dose pentavalent rotavirus vaccine recipients, 770 were >12 weeks of age. Hospital-based providers were less likely to administer pentavalent rotavirus vaccine off-label. With the current level of vaccine implementation and current pentavalent rotavirus vaccine recommendations for series initiation, a substantial proportion of children are expected to be excluded from receiving any pentavalent rotavirus vaccine or completing the series. In the first 6 months of availability, pentavalent rotavirus vaccine frequently was used off-label for age, underscoring the importance of education of immunization providers. Current outreach programs for finding 10-month-old toddlers delinquent for immunizations will not improve the possibility of protection against rotavirus.
  PEDIATRICS 08/2008; 122(1):e33-8. · 4.47 Impact Factor
• Article: Effect of accessibility of influenza vaccination on the rate of childcare staff vaccination.

  Ingi Lee, Sarah Thompson, Ebbing Lautenbach, Leanne B Gasink, Barbara Watson, Neil O Fishman, Zhen Chen, Darren R Linkin
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  ABSTRACT: We assessed the impact of free on-site influenza vaccination on childcare staff vaccination prevalence using 2 before-and-after studies. Vaccination was offered during the 2003-2004 and 2006-2007 influenza seasons. Staff vaccination prevalence was higher in each intervention season compared to the prior, nonintervention season. No baseline characteristics were associated with receipt of vaccination.
  Infection Control and Hospital Epidemiology 06/2008; 29(5):465-7. · 3.67 Impact Factor
• Article: Humoral and cell-mediated immune responses in children and adults after 1 and 2 doses of varicella vaccine.

  Barbara Watson
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  ABSTRACT: Humoral and cell-mediated immune responses to varicella-zoster virus (VZV) have been evaluated after 1 and 2 doses of live attenuated varicella vaccine, Oka strain, in several studies. One dose of varicella vaccine, however, elicits detectable immune responses that are low and, in some cases, may be insufficient for complete protection against the virus after the normal decline in humoral and cell-mediated immunity with time. In contrast, immune responses after 2 doses are significantly higher and approximate the levels seen after natural disease. These investigations of vaccine-induced immunity suggest that 2 doses of VZV vaccine will better achieve the goals of the VZV vaccination program, by reducing the VZV burden of disease in childhood and preventing accumulation of young adults who are susceptible to or only partially protected from varicella.
  The Journal of Infectious Diseases 04/2008; 197 Suppl 2:S143-6. · 6.41 Impact Factor
• Article: Performance of an algorithm for assessing smallpox risk among patients with rashes that may be confused with smallpox.

  Sonja S Hutchins, Iddrisu Sulemana, Katherine L Heilpern, William Schaffner, Gary Wax, E Brooke Lerner, Barbara Watson, Robert Baltimore, Rachel A Waltenburg, Dominik Aronsky, Susan Coffin, Gladys Ng, Allen S Craig, Amy Behrman, James Meek, Eileen Sherman, Sandra S Chavez, Rafael Harpaz, Scott Schmid
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  ABSTRACT: After the 2001 anthrax bioterror attacks, the Centers for Disease Control and Prevention developed an algorithm to evaluate patients rapidly for suspected smallpox. A prospective, multicenter study examined the performance of this algorithm in assessing patients with an acute, generalized vesicular or pustular rash (AGVPR) admitted to emergency departments and inpatient units of 12 acute-care hospitals in 6 states. Of 26,747 patients (3.5% of all admissions) with rashlike conditions screened, 89 (1.2 patients per 10,000 admissions) had an AGVPR. Physicians or study staff classified none of 73 enrolled patients as being at high risk for having smallpox; 72 (99%) were classified as being at low risk, and 1 was classified as being at moderate risk. The discharge diagnosis for 55 (75%) of these 73 participants was varicella illness. Use of the algorithm did not result in misclassification of AGVPR as high risk for smallpox. The algorithm is a highly specific tool for clinical evaluation of suspected smallpox disease.
  Clinical Infectious Diseases 04/2008; 46 Suppl 3:S195-203. · 9.15 Impact Factor
• Source

  Available from: unjbg.edu.pe

  Article: Routine laboratory testing data for surveillance of rotavirus hospitalizations to evaluate the impact of vaccination.

  Manish M Patel, Jacqueline E Tate, Rangaraj Selvarangan, Irini Daskalaki, Mary Anne Jackson, Aaron T Curns, Susan Coffin, Barbara Watson, Richard Hodinka, Roger I Glass, Umesh D Parashar
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  ABSTRACT: The recent implementation of a rotavirus vaccination program in the United States makes it imperative to assess the impact of immunization on the incidence of severe rotavirus disease leading to hospitalization. Active surveillance for laboratory-confirmed rotavirus hospitalizations is the ideal approach for surveillance, but requires substantial resources to implement. We examined laboratory and hospital discharge data for 2 tertiary care pediatric hospitals to assess the utility of routine laboratory testing data for surveillance of rotavirus gastroenteritis and to estimate rotavirus disease burden. We obtained all discharge records of hospitalizations for acute gastroenteritis among children <5 years of age at Children's Mercy Hospital (CMH), Kansas City, from July 2000 to June 2005 and at Children's Hospital of Philadelphia (CHOP) from July 2004 to June 2006. We linked these discharge records to laboratory results of rotavirus testing to evaluate epidemiologic differences in children who were tested and not tested for rotavirus and to estimate overall rotavirus burden by extrapolating clinical testing results to the untested group. At CMH, of the 3702 children with acute gastroenteritis, 69% (n = 2552) were discharged during the winter (January through May) months, when rotavirus is most common. Similarly, at CHOP, 62% (n = 779) of the 1261 gastroenteritis discharges occurred during the winter months. During these months, 47% (n = 1197 of 2552) of the discharges at CMH and 56% (n = 438 of 779) of the discharges at CHOP were tested for rotavirus and of those tested, 71% (n = 853 of 1197) and 55% (n = 242 of 438) were positive, respectively. At both hospitals, children with and without rotavirus testing had similar gender and race/ethnicity, but the rate of testing differed by age at CHOP and by month of admission at CMH. After adjusting for these differences, we estimate that 56%-70% of winter and 34%-48% of year-round gastroenteritis in children <5 years can be attributable to rotavirus. Overall, 3%-5% of all hospitalizations in children <5 years of age were caused by rotavirus. Sentinel hospitals where a large proportion of children hospitalized for gastroenteritis are routinely tested for rotavirus could provide a useful and cost-efficient platform to complement ongoing active surveillance efforts to evaluate the impact of rotavirus vaccination. The data reaffirm the substantial burden of rotavirus hospitalizations in US children and the potential health benefits of vaccination.
  The Pediatric Infectious Disease Journal 11/2007; 26(10):914-9. · 3.58 Impact Factor
• Article: Hepatitis A outbreak activity in the United States: responding to a vaccine-preventable disease.

  Allen S Craig, Barbara Watson, Thomas K Zink, Jeffrey P Davis, Chang Yu, William Schaffner
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  ABSTRACT: The occurrence of hepatitis A in the United States is heterogeneous because of disease cycles with substantial variation in incidence among states and involvement of numerous behavioral risk factors. In spite of the Advisory Committee on Immunization Practices' (ACIP) 1999 recommendation for routine hepatitis A immunization in states with high rates of disease and the fact that disease rates are at a historic low, outbreaks continue to occur. We reviewed outbreaks of hepatitis A in the United States occurring from 1994 through 2004. We searched PubMed, ProMed, Google, and the CDC Foodborne Disease Outbreak and Epi-X Internet sites to ascertain the number and type of hepatitis A outbreaks. The CDC's MMWR publication and the Hepatitis Control Report were also searched. A total of 256 hepatitis A outbreaks were identified from 1994 through 2004. The mean number of outbreaks was 23 per year (median 25). The number of outbreaks in states with traditionally low/intermediate endemic rates of hepatitis A remained relatively constant during the study period. Outbreaks declined significantly (P = 0.01) in states with previously high rates of disease--most of which have implemented hepatitis A vaccination programs. Outbreaks of hepatitis A continue to occur in the United States despite the licensure of two safe and effective vaccines in 1995 and the apparent decline in the number of outbreaks in states with previously high rates of hepatitis A. The recent ACIP recommendation for universal hepatitis A vaccination at age 1 year in all states will contribute to a further reduction in hepatitis A outbreaks.
  The American Journal of the Medical Sciences 10/2007; 334(3):180-3. · 1.39 Impact Factor
• Article: Neurologic complications in children hospitalized with influenza: characteristics, incidence, and risk factors.

  Jason G Newland, V Matt Laurich, Anna W Rosenquist, Kateri Heydon, Daniel J Licht, Ron Keren, Theoklis E Zaoutis, Barbara Watson, Richard L Hodinka, Susan E Coffin
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  ABSTRACT: To determine the characteristics, incidence, and risk factors for influenza-related neurologic complications (INC). A retrospective cohort study of INC in children hospitalized with laboratory-confirmed influenza infection (LCI) from June 2000 to May 2004 was conducted. Systematic chart review was performed to identify clinical characteristics and outcomes. A neighborhood cohort was constructed to estimate the incidence of INC. Logistic regression was used to identify independent risk factors for INC. Of 842 patients with LCI, 72 patients had an INC: influenza-related encephalopathy (8), post-infectious influenza encephalopathy (2), seizures (56), and other (6). Febrile seizures were the most common type of seizures (27). No patient died from an INC. In our neighborhood cohort, the incidence of INC was 4 cases per 100,000 person-years. An age of 6 to 23 months (odds ratio [OR], 4.2; 95% CI, 1.4-12.5) or 2 to 4 years (OR, 6.3; 95% CI, 2.1-19.1) and an underlying neurologic or neuromuscular disease (OR, 5.6; 95% CI, 3.2-9.6) were independent risk factors for the development of INC. Seizures are the most common neurologic complication experienced by children hospitalized with influenza. In the United States, encephalopathy is uncommon. Young children and patients with neurologic or neuromuscular disease are at increased risk for INC.
  The Journal of pediatrics 04/2007; 150(3):306-10. · 4.02 Impact Factor
• Article: Incidence, complications, and risk factors for prolonged stay in children hospitalized with community-acquired influenza.

  Susan E Coffin, Theoklis E Zaoutis, Anna B Wheeler Rosenquist, Kateri Heydon, Guillermo Herrera, Carolyn B Bridges, Barbara Watson, Russell Localio, Richard L Hodinka, Ron Keren
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  ABSTRACT: Few studies have examined the characteristics and clinical course of children hospitalized with laboratory-confirmed influenza. We sought to (1) estimate the age-specific incidence of influenza-related hospitalizations, (2) describe the characteristics and clinical course of children hospitalized with influenza, and (3) identify risk factors for prolonged hospitalization. Children < or = 21 years of age hospitalized with community-acquired laboratory-confirmed influenza at a large urban children's hospital were identified through review of laboratory records and administrative data sources. A neighborhood cohort embedded within our study population was used to estimate the incidence of community-acquired laboratory-confirmed influenza hospitalizations among children < 18 years old. Risk factors for prolonged hospitalization (> 6 days) were determined by using logistic regression. We identified 745 children hospitalized with community-acquired laboratory-confirmed influenza during the 4-year study period. In this urban cohort, the incidence of community-acquired laboratory-confirmed influenza hospitalization was 7 per 10,000 child-years of observation. The median age was 1.8 years; 25% were infants < 6 months old, and 77% were children < 5 years old. Many children (49%) had a medical condition associated with an increased risk of influenza-related complications. The incidence of influenza-related complications was higher among children with a preexisting high-risk condition than for previously healthy children (29% vs 21%). However, only cardiac and neurologic/neuromuscular diseases were found to be independent risk factors for prolonged hospitalization. Influenza is a common cause of hospitalization among both healthy and chronically ill children. Children with cardiac or neurologic/neuromuscular disease are at increased risk of prolonged hospitalization; therefore, children with these conditions and their contacts should be a high priority to receive vaccine. The impact on pediatric hospitalization of the new recommendation to vaccinate all children 6 months to < 5 years old should be assessed.
  PEDIATRICS 04/2007; 119(4):740-8. · 4.47 Impact Factor
• Article: Varicella-zoster vaccine in the USA: success for control of disease severity, but what next?

  Barbara Watson
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  ABSTRACT: In the period from 1990 to 1994, before the introduction of a varicella vaccine to the USA, approximately 100 deaths in otherwise healthy individuals, children and adolescents under 20 years of age, were attributable to varicella complications. The administration of a single-dose vaccine has now been widespread in the USA for nearly 10 years; however, since the effectiveness of a single dose in children under 13 years of age in an outbreak situation is approximately 80%, consideration of a second booster dose is in progress although not yet recommended. Licensure of a measles-mumps-rubella-varicella vaccine may hasten the recommendation.
  Expert Review of Anticancer Therapy 03/2005; 3(1):105-15. · 3.28 Impact Factor
• Article: Chickenpox outbreak in a highly vaccinated school population.

  Karl Heath, Barbara Watson
  PEDIATRICS 11/2004; 114(4):1130-1; author reply 1131. · 4.47 Impact Factor
• Article: Ten year follow-up of healthy children who received one or two injections of varicella vaccine.

  Barbara Kuter, Holly Matthews, Henry Shinefield, Steve Black, Penelope Dennehy, Barbara Watson, Keith Reisinger, Lee Lian Kim, Lisa Lupinacci, Jonathan Hartzel, Ivan Chan
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  ABSTRACT: The rate of varicella and persistence of varicella antibody after a one dose vs. a two dose regimen of varicella virus vaccine live Oka/Merck (VARIVAX; Merck & Co., Inc., West Point, PA) in approximately 2000 children were compared during a 9- to 10-year follow-up period. Children 12 months to 12 years of age with a negative history of varicella were randomized in late 1991 to early 1993 to receive either one or two injections of varicella vaccine given 3 months apart. Subjects were actively followed for varicella, any varicella-like illness or zoster and any exposures to varicella or zoster on a yearly basis for 10 years after vaccination. Persistence of varicella antibody was measured yearly for 9 years. Most cases of varicella reported in recipients of one or two injections of vaccine were mild. The risk of developing varicella >42 days postvaccination during the 10-year observation period was 3.3-fold lower (P < 0.001) in children who received two injections than in those who received one injection (2.2% vs. 7.3%, respectively). The estimated vaccine efficacy for the 10-year observation period was 94.4% for one injection and 98.3% for two injections (P < 0.001). Measurable serum antibody persisted for 9 years in all subjects. Administration of either one or two injections of varicella vaccine to healthy children results in long term protection against most varicella disease. The two dose regimen was significantly more effective than a single injection.
  The Pediatric Infectious Disease Journal 03/2004; 23(2):132-7. · 3.58 Impact Factor
• Article: Safety, immunogenicity and efficacy in healthy infants of G1 and G2 human reassortant rotavirus vaccine in a new stabilizer/buffer liquid formulation.

  H Fred Clark, Carl J Burke, David B Volkin, Paul Offit, Richard L Ward, Joseph S Bresee, Penelope Dennehy, W Manfred Gooch, Edgardo Malacaman, David Matson, Emmanuel Walter, Barbara Watson, David L Krah, Michael J Dallas, Florian Schödel, karen M Kaplan, Penny Heaton
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  ABSTRACT: A refrigerator-stable rotavirus (RV) vaccine that withstands gastric acid is anticipated to permit more widespread use of RV vaccine. We investigated for the first time in infants an oral, liquid formulation of G1 and G2 human bovine reassortant rotavirus vaccine (HRRV) with a new stabilizer/buffer (S/B) containing sucrose, sodium phosphate and sodium citrate. During 1997 through 1998, 731 healthy infants approximately 2 to 4 months of age were enrolled at 19 US sites to receive 3 HRRV or placebo doses approximately 6 to 8 weeks apart in a partially double blinded study. Infants were randomized to: (1) HRRV with no S/B but with prefeeding; (2) HRRV plus 1 of 3 different concentrations/volumes of S/B; or (3) placebo. No serious vaccine-related adverse experiences or intussusception cases were reported. No statistically significant differences were observed between vaccine and placebo recipients for fever (> or =38.1 degrees C) 0 to 7 days after any dose, irritability, vomiting or diarrhea incidence 0 to 42 days after any dose. Vaccine virus shedding among vaccine recipients was uncommon. Among S/B vaccine groups, proportions of infants with a > or =3-fold titer rise from baseline to Postdose 3 for G1 serum-neutralizing antibody (SNA), G2 SNA, WC3 SNA, serum anti-RV IgA, serum anti-RV IgG and stool anti-RV IgA were generally similar to those of the prefed non-S/B group. HRRV with a new S/B was generally well-tolerated; immunogenicity was generally similar to the prefed non-S/B group. No intussusception cases were reported, but the small sample size precluded a definitive conclusion. A large international clinical study is under way to address safety and efficacy of an S/B formulation of a pentavalent version of HRRV.
  The Pediatric Infectious Disease Journal 10/2003; 22(10):914-20. · 3.58 Impact Factor
• Article: A cluster of primary varicella cases among healthcare workers with false-positive varicella zoster virus titers.

  Amy Behrman, D Scott Schmid, Anne Crivaro, Barbara Watson
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  ABSTRACT: Five cases of primary varicella zoster virus (VZV) we re diagnosed among hospital healthcare workers (HCWs). All had complied with a pre-employment VZV screening program and had been considered immune. To summarize the investigation of VZV among un-immunized HCWs and to provide recommendations for avoiding false-positive serologic tests. Risk of transmission of VZV to susceptible HCWs is minimized through serologic screening. Varicella vaccine is recommended for susceptible HCWs. A commercially available latex bead agglutination assay (LA) is widely used because it is rapid and easy to perform. LA was compared with the whole-cell varicella ELISA standardized in the Centers for Disease Control and Prevention (CDC) National Herpes Laboratory. SETTING/POPULATION: Large inner-city, tertiary-employee population. In a year, 5 HCWs presented with laboratory-confirmed primary varicella infection. Four had VZV exposures 2 weeks prior to presentation. All had documented positive VZV titers by LA performed at hire. None were offered VZV vaccination. The original LAs were judged false-positives. INTERVENTION/FOLLOW-UP INVESTIGATION: Fifty-three consecutive VZV LA samples from the hospital laboratory were retested at the CDC. Forty-four samples concurred. Of the remaining 9, 4 were positive by hospital LA but negative by CDC IgG ELISA. Four were equivocal by hospital LA but negative by CDC IgG ELISA and LA. One was positive by hospital LA but negative by LA and equivocal by ELISA at the CDC. LA may be prone to false-positive results and inappropriate for screening hospital HCWs.
  Infection Control and Hospital Epidemiology 04/2003; 24(3):202-6. · 3.67 Impact Factor
• Article: Varicella: a vaccine preventable disease?

  Barbara Watson
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  ABSTRACT: To present a review of varicella disease, vaccine development and implementation of universal vaccination, discuss common questions about the vaccine and the epidemiology of the disease since licensure of the varicella vaccine. Review the incidence of complications from varicella disease prior to vaccine licensure, safety of the varicella vaccine from clinical trials and post-marketing surveillance data, the impact of the vaccine on disease incidence where high vaccine coverage has been achieved, and address some barriers to vaccination. Raise issues that developed since 1995. The safety data gathered during the 20-year-gestation period of this vaccine prior to licensure has been confirmed. The vaccine works-in areas where vaccine coverage is over 70%, there has been a decline in disease, most marked in the age group with the best vaccine coverage (the 1-4-year olds), leading to a concern that unexposed susceptible children may reach adulthood and remain susceptible unless better practice of universal vaccination of ALL susceptible is practiced. Varicella disease has declined in areas with moderate vaccine coverage. Continued implementation of existing vaccine policies will lead to further reductions of varicella morbidity and mortality throughout the USA.
  Journal of Infection 06/2002; 44(4):220-5. · 4.13 Impact Factor
• Article: Validity of self-reported varicella disease history in pregnant women attending prenatal clinics.

  Barbara Watson, Rachel Civen, Meredith Reynolds, Karl Heath, Dana Perella, Tina Carbajal, Laurene Mascola, Aisha Jumaan, Laura Zimmerman, Abike James, Carlene Quashi, Scott Schmid
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  ABSTRACT: The purpose of this study was to assess the validity of self-reported history for varicella disease relative to serological evidence of varicella immunity in pregnant women attending antenatal care at clinics located in two diverse geographical locations in the U.S. (Antelope Valley, California, and Philadelphia) with high varicella vaccination coverage. Pregnant women attending prenatal care appointments who needed blood drawn as part of their routine care were eligible to participate. Self-reported varicella disease history was obtained via questionnaire. Varicella serostatus was determined using a whole-cell enzyme-linked immunosorbent assay to test for varicella zoster virus-specific immunoglobulin G (VZV IgG) antibodies. Of the 309 study participants from Antelope Valley and the 528 participants from Philadelphia who self-reported having had chickenpox disease, 308 (99.7%; 95% confidence interval [CI]: 98.2, 100) and 517 (97.9%; 95% CI: 96.3, 99.0), respectively, had serological evidence of immunity to varicella. Only 6.8% (95% CI: 3.9, 11.0) and 17.4% (95% CI: 13.1, 22.5) of women who self-reported having a negative or uncertain varicella disease history in Antelope Valley and Philadelphia, respectively, were seronegative for varicella antibodies. Despite the dramatic changes in the epidemiology of varicella that have occurred since 1995 due to the introduction and subsequent widespread use of the varicella vaccine, self-reported history of varicella continues to be a strong predictor of VZV IgG antibodies in pregnant women. Negative or uncertain history remains poorly predictive of negative serostatus.
  Public Health Reports 122(4):499-506. · 1.27 Impact Factor
• Source

  Available from: Susmita Pati

  Article: Identifying infants at increased risk for late initiation of immunizations: maternal and provider characteristics.

  Kristen A Feemster, C Victor Spain, Michael Eberhart, Susmita Pati, Barbara Watson
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  ABSTRACT: We identified maternal, provider, and community predictors among infants for late initiation of immunizations. We performed a retrospective cohort study of infants born between January 1, 2002, and December 31, 2004, in Philadelphia, Pennsylvania. Primary outcomes were age in days at first office-based immunization and status as a late starter (i.e., initiating office-based immunizations after 90 days of age). Candidate predictors included sociodemographic and prenatal characteristics, immunization provider practice type and size, and neighborhood factors. We performed hierarchical logistic regression and Cox regression models to identify independent predictors for being a late starter and prolonged time to first immunization. Of the 65,519 infants from this birth cohort in Philadelphia's immunization registry, 54,429 (88.1%) were included in analysis and 12.6% of these were late starters. Infants whose mothers were younger, received less than five prenatal visits, had less than a high school education, had more than two children, and who smoked cigarettes prenatally were significantly more likely to be late starters. Receiving care at hospital/university-based or public health clinics was also significantly associated with likelihood of being a late starter. Neither distance between infant's residence and practice nor neighborhood socioeconomic indicators was independently associated with the outcomes. Common risk factor profiles based on practice type and four maternal characteristics were found to reliably identify infant risk. Maternal receipt of fewer prenatal care visits, younger maternal age, higher birth order, and receiving care at public health clinics were the strongest predictors of being a late starter and time to first immunization. Risk factor profiles based on information already collected at birth can be used to identify higher-risk infants. Early intervention and potentially partnering with prenatal care providers may be key strategies for preventing underimmunization.
  Public Health Reports 124(1):42-53. · 1.27 Impact Factor