[Show description][Hide description]DESCRIPTION: On January 29, 2015, the city of Tampere environmental health officers were informed of a possible foodborne outbreak among customers who had eaten lunch in restaurant X. Employees of electric companies A and B had a sudden onset of gastrointestinal symptoms. We conducted a retrospective cohort study to identify the vehicle, source, and causative agent of the outbreak. A case was defined as an employee of companies A or B with diarrhea and/or vomiting who ate lunch at Restaurant X on January 26, 2015. All employees of the companies attending the implicated lunch were invited to participate in the cohort study. Environmental investigation was conducted. Twenty-one responders were included in statistical analysis, of which 11 met with the case definition. Of the 15 food items consumed by participants, four food items were associated with gastroenteritis. Of four kitchen staff, three tested positive for norovirus GIP7, the strain was found earlier in the community. No patient samples were obtained. Level of hygiene in the kitchen was inadequate. Infected kitchen staff probably transmitted norovirus by inadequate hygiene practices. No new cases associated with Restaurant X were reported after the hygiene practices were improved.
[Show abstract][Hide abstract]ABSTRACT: On January 29, 2015, the city of Tampere environmental health officers were informed of a possible foodborne outbreak among customers who had eaten lunch in restaurant X. Employees of electric companies A and B had a sudden onset of gastrointestinal symptoms. We conducted a retrospective cohort study to identify the vehicle, source, and causative agent of the outbreak. A case was defined as an employee of companies A or B with diarrhea and/or vomiting who ate lunch at Restaurant X on January 26, 2015. All employees of the companies attending the implicated lunch were invited to participate in the cohort study. Environmental investigation was conducted. Twenty-one responders were included in statistical analysis, of which 11 met with the case definition. Of the 15 food items consumed by participants, four food items were associated with gastroenteritis. Of four kitchen staff, three tested positive for norovirus GIP7, the strain was found earlier in the community. No patient samples were obtained. Level of hygiene in the kitchen was inadequate. Infected kitchen staff probably transmitted norovirus by inadequate hygiene practices. No new cases associated with Restaurant X were reported after the hygiene practices were improved.
[Show abstract][Hide abstract]ABSTRACT: The baseline national invasive pneumococcal disease (IPD) incidence rate, serotype distribution and serotype coverage of pneumococcal vaccines were evaluated in patients with Hodgkin's and non-Hodgkin's lymphomas, myeloma and leukaemia within 1 year after haematological diagnosis during 1995-2002, before introduction of pneumococcal conjugate vaccines. Pneumococcal serotype distribution among these patients was different from serotypes causing IPD in the general population. The serotype coverages of PCV13 and PPSV23 were 57% and 64%, respectively, lower than in the general population. This reflects a higher predisposition to IPD in vaccinated patients with haematological malignancies and possibly less benefit of herd immunity gained with the wide use of pneumococcal conjugate vaccines in the general population. This data will be useful as a baseline for determining the future role of adult PCV vaccination in these patient groups.
[Show abstract][Hide abstract]ABSTRACT: Background:
Most of the commonly used diabetes mellitus screening tools and risk scores have been developed with American or European populations in mind. Their applicability, therefore, to low and middle-income countries remains unquantified. Simultaneously, low and middle-income countries including Mongolia are currently witnessing rising diabetes prevalence. This research aims to develop and validate a diabetes risk score for the screening of undiagnosed type 2 diabetes mellitus in the Mongolian adult population.
Blood glucose measurements from 1018 Mongolians, as well as information on demography and risk factors prevalence was drawn from 2009 STEPS data. Existing risk scores were applied, measuring sensitivity using area under ROC-curves. Logistic regression models were used to identify additional independent predictors for undiagnosed diabetes. Finally, a new risk score was developed and Hosmer-Lemeshow tests were used to evaluate the agreement between the observed and predicted prevalence.
The performance of existing risk scores to identify undiagnosed diabetes was moderate; with the area under ROC curves between 61-64 %. In addition to well-established risk factors, three new independent predictors for undiagnosed diabetes were identified. Incorporating these into a new risk score, the area under ROC curves increased to 77 % (95 % CI 71 %-82 %).
Existing European or American diabetes risk tools cannot be adopted in Asian countries without prior validation in the specific population. With this in mind, a low-cost, reliable screening tool for undiagnosed diabetes was developed and internally validated for Mongolians. The potential for cost and morbidity savings could be significant.
Full-text · Article · Sep 2015 · BMC Public Health
[Show abstract][Hide abstract]ABSTRACT: To describe the epidemiology of intussusception before introduction of the rotavirus vaccine, we reviewed the records of 280
patients younger than 5 years who were hospitalized in Kenya between 2002 and 2013. The patients who died (18 [6.4%]) had
sought care later after symptom onset than the patients who survived (median, 5 vs 3 days, respectively; P = .04). Seeking prompt care may improve therapeutic outcomes.
[Show abstract][Hide abstract]ABSTRACT: Increasing immigration from high tuberculosis (TB) incidence countries is a challenge for surveillance and control in Finland. Here, we describe the epidemiology of TB in immigrants by using national surveillance data. During 1995–2013, 7030 (84·7%) native and 1199 (14·4%) immigrant cases were identified. The proportion of immigrant cases increased from 5·8% in 1995 to 32·1% in 2013, consistent with increasing immigrant population (2·1–5·6%) and decreasing incidence of TB in the native population (from 12·1 to 3·5/100 000). TB cases in immigrants were significantly younger, more often female, and had extrapulmonary TB more often than native cases (
< 0·01 for all comparisons); multidrug resistance was also more common in immigrants than natives (
< 0·01). Immigrant cases were born in 82 different countries; most commonly in Somalia and the former Soviet Union/Russia. During 2008–2013, 433
isolates from immigrants were submitted for spoligotyping; 10 different clades were identified. Clades were similar to those found in the case's country of birth. Screening immigrants from high-incidence countries and raising awareness of common characteristics and symptoms of TB is important to ensure early diagnosis and to prevent transmission.
No preview · Article · Jul 2015 · Epidemiology and Infection
[Show abstract][Hide abstract]ABSTRACT: Frequent foodborne outbreaks occurring in large canteens of factories and schools are a public health concern in Vietnam. Potential for contamination of food during the preparation phase has not yet been addressed by public health authorities, particularly the food-handlers’ knowledge, attitudes and practices (KAP) regarding food safety. To identify training needs, we conducted an analytical cross-sectional study assessing KAP of food-handlers in large canteens of schools and factories in 2012. From a sampling frame of 169 large canteens (50 in schools and 119 in factories; a total of 3,399 employees) in Southern Vietnam, 40 schools and 26 factories were selected on the basis of type of establishment; all food-handlers (N=909) in the selected canteens were interviewed by using standard questionnaire. After descriptive analysis, potential confounders were controlled by using logistic regression models to calculate prevalence odds ratios (PORs) and 95% confidence intervals (CI) for differences in KAP between employees in schools and factories. A qualitative study of ten focus groups with participants selected by using maximum variation sampling was also conducted to identify training needs. Of the 909 food-handlers participating the study, 76% were females, 84% had secondary school or higher education; median age and work experience were 38 years and 36 months, respectively. Proportions of all participants whose KAP were considered adequate were 26%, 36%, and 26%, respectively. There were associations between knowledge and attitudes, and knowledge and practices. After controlling for gender, age, educational level, and length of work experience in logistic regression models, the odds of food-handlers in schools reporting adequate KAP were about twice as high as those for food-handlers in factories. Among 66 investigated canteens, 9% did not separate raw food from cooked food area and 52% did not have standard rest rooms. Food-handlers’ suggestions for training needs included appropriate location of the training venue at the work place, involvement of managers, fewer trainees per course, more practical exercises, and longer course duration. KAP of food-handlers were generally poor, especially among food-handlers working in factories. Public health authorities in Vietnam should prioritize for food-handlers in factories for training courses.
[Show abstract][Hide abstract]ABSTRACT: The ten-valent pneumococcal conjugate vaccine (PCV10) was introduced into the Finnish National Vaccination Program (NVP) in September 2010 with a 2+1 schedule (3, 5, 12 months) without catch-up vaccinations. We evaluated the direct and indirect effects of PCV10 on invasive pneumococcal disease (IPD) among children ≤5 years of age during the first three years after NVP introduction.
We conducted a population-based, observational follow-up study. The cohort of vaccine-eligible children (all children born June 1, 2010 or later) was followed from 3 months of age until the end of 2013. For the indirect effect, another cohort of older children ineligible for PCV10 vaccination was followed from 2011 through 2013. Both cohorts were compared with season- and age-matched reference cohorts before NVP introduction. National, population-based laboratory surveillance data were used to compare culture-confirmed serotype-specific IPD rates in the vaccine target and reference cohorts by using Poisson regression models.
The overall IPD rate among vaccine-eligible children was reduced by 80% (95%CI 72 to 85); the reduction in vaccine-type IPD was 92% (95%CI 86 to 95). However, a non-significant increase in non-vaccine type IPD was observed. During 2012-2013, we also observed a 48% (95%CI 18 to 69) reduction in IPD among unvaccinated children 2 to 5 years of age, which was mostly attributable to the ten vaccine serotypes.
This is the first population-based study investigating the impact of PCV10 introduction without prior PCV7 use. A substantial decrease in IPD rates among vaccine-eligible children was observed. A smaller and temporally delayed reduction among older, unvaccinated children suggests that PCV10 also provides indirect protection against vaccine-type IPD. Changes in serotype distribution warrant continuous monitoring of potential increases in non-vaccine serotypes.
[Show abstract][Hide abstract]ABSTRACT: Objectives
To identify the vehicle, source, and causative agent of a community-wide food-borne outbreak of gastroenteritis.
We conducted a case–control study. Cases were city residents diagnosed with gastroenteritis and hospitalized in Ben Tre City from 22 to 25 May 2013; 41 cases were selected randomly from a list of hospitalized patients. Controls were age- and gender-matched healthy neighbours of cases. Participants were interviewed using a standard questionnaire. Samples from patients and food were tested at reference laboratories. We used conditional logistic regression to calculate matched odds ratios (mORs) for the association of gastroenteritis with food items consumed.
Of the 41 cases enrolled in the study, 61% were males and the median age was 33 years; cases resided in 12 wards of the City. Of 13 food items consumed by the cases, only stuffed bread was significantly associated with gastroenteritis (mOR 21.3, 95% confidence interval 6.3–71.8). Among the 29 cases who ate stuffed bread, the median time to illness onset was 9 h. Patient stool samples and bread samples were positive for Salmonella species.
Stuffed bread was the likely vehicle of the outbreak. The laboratory testing capacity for serotypes of Salmonella should be strengthened in Vietnam. Food-handler training in basic food safety measures should be improved.
Full-text · Article · Jul 2014 · International Journal of Infectious Diseases
[Show abstract][Hide abstract]ABSTRACT: An outbreak of gastroenteritis occurred among workers of company X after eating lunch prepared by a catering service. Of 430 workers attending the meal, 56 were hospitalized with abdominal pain, diarrhea, vomiting, and nausea, according to the initial report. We conducted an investigation
to identify the extent, vehicle, and source of the outbreak. In our case-control study, a case was a worker who attended the meal and who was hospitalized with acute gastroenteritis; controls were randomly selected from non-ill workers. Cases and controls were interviewed using a standard
questionnaire. We used logistic regression to calculate adjusted odds ratios for the consumption of food items. Catering service facilities and food handlers working for the service were inspected. Food samples from the catering service were tested at reference laboratories. Of hospitalized
cases, 54 fulfilled the case definition, but no stool specimens were collected for laboratory testing. Of four food items served during lunch, only “squash and pork soup” was significantly associated with gastroenteritis, with an adjusted odds ratio of 9.5 (95 % CI 3.2, 27.7).
The caterer did not separate cooked from raw foods but used the same counter for both. Cooked foods were kept at room temperature for about 4 h before serving. Four of 14 food handlers were not trained on basic food safety principles and did not have health certificates. Although no microbiological
confirmation was obtained, our epidemiological investigation suggested that squash and pork soup caused the outbreak. Hospitals should be instructed to obtain stool specimens from patients with gastroenteritis. Food catering services should be educated in basic food safety measures.
No preview · Article · Jul 2014 · Journal of food protection
[Show abstract][Hide abstract]ABSTRACT: On July 20, 2010, three cases of cholera were reported from a district hospital in Ca Mau province, Vietnam. We investigated the likely source and mode of transmission of the outbreak. All hospitals in the province were requested to notify cases of acute watery diarrhoea. Epidemiological, clinical, and laboratory data were collected. Between July 12 and 22, seven cases with positive culture for Vibrio cholera were identified. Six cases were epidemiologically linked to the index case. Basic infection control practices were not in place at the hospital. Clinicians and public health staff should consider the possibility of nosocomial cholera transmission even in non-endemic areas.
Full-text · Article · Dec 2013 · The Journal of Infection in Developing Countries
[Show abstract][Hide abstract]ABSTRACT: SUMMARY Few population-based data are available on factors associated with pneumonic and ulceroglandular type B tularaemia. We conducted a case-control study during a large epidemic in 2000. Laboratory-confirmed case patients were identified through active surveillance and matched control subjects (age, sex, residency) from the national population information system. Data were collected using a self-administered questionnaire. A conditional logistic regression model addressing missing data with Bayesian full-likelihood modelling included 227 case patients and 415 control subjects; reported mosquito bites [adjusted odds ratio (aOR) 9·2, 95% confidence interval (CI) 4·4-22, population-attributable risk (PAR) 82%] and farming activities (aOR 4·3, 95% CI 2·5-7·2, PAR 32%) were independently associated with ulceroglandular tularaemia, whereas exposure to hay dust (aOR 6·6, 95% CI 1·9-25·4, PAR 48%) was associated with pneumonic tularaemia. Although the bulk of tularaemia type B disease burden is attributable to mosquito bites, risk factors for ulceroglandular and pneumonic forms of tularaemia are different, enabling targeting of prevention efforts accordingly.
Full-text · Article · Dec 2013 · Epidemiology and Infection
[Show abstract][Hide abstract]ABSTRACT: Background:
Nasopharyngeal (NP) carriage and invasive pneumococcal disease (IPD) attributable to serotypes in the 7-valent pneumococcal conjugate vaccine (PCV7) declined dramatically after vaccine introduction, whereas non-PCV7 serotypes increased modestly. Characteristics of pneumococcal carriage and IPD among children in Atlanta, GA, were compared during 2 time periods: before PCV7 introduction and before 13-valent PCV (PCV13) introduction.
NP swabs from 231 and 451 children 6-59 months old receiving outpatient medical care were obtained in 1995 and 2009, respectively. A total of 202 and 47 IPD cases were identified in children younger than 5 years of age in 1995 and in 2008 to 2009, respectively, through active, population-based surveillance in Atlanta. Isolates were serotyped, sequence-typed (ST) and tested for antimicrobial susceptibility.
Forty percent (93/231) of children in 1995 and 31% (139/451) in 2009 were colonized with Streptococcus pneumoniae; 60% and 0.7% were PCV7 serotypes, respectively. In 1995, PCV7 serotypes accounted for 83% and 19A accounted for 5% of IPD compared with no PCV7 serotypes and 19A accounting for 49% of IPD in 2009 (P < 0.001). In 2009, PCV13 serotypes accounted for 22% of carriage (mostly 19A) and 60% of invasive isolates (P < 0.001). ST320 accounted for 66% and 52% of 19A carriage and IPD isolates in 2009, respectively; all ST320 isolates were multidrug-resistant. No ST320 NP or IPD isolates were identified before PCV7.
Serotype distribution among NP and IPD isolates in Atlanta has shifted to non-PCV7 serotypes; 19A was the leading serotype for both. The multidrug-resistant ST320 strain was responsible for two-thirds of 19A carriage isolates and half of IPD isolates. The predominance of serotype 19A in carriage and IPD among children in Atlanta highlights the potential direct and indirect benefits anticipated by implementation of PCV13 in the community.
No preview · Article · Oct 2012 · The Pediatric Infectious Disease Journal
[Show abstract][Hide abstract]ABSTRACT: Since 1997, the Advisory Committee on Immunization Practices has recommended the 23-valent pneumococcal polysaccharide vaccine (PPSV23) for nonelderly adults with certain medical conditions. In 2008, the Committee added asthma and cigarette smoking to the list of indications for PPSV23 vaccination. Using data from the 2009 National Health Interview Survey, the authors assessed PPSV23 uptake in people with established and new indications. To identify factors independently associated with receiving PPSV23, they used multivariable logistic regression and predictive marginal analyses. In 2009, a total of 35.2 million adults 18-64 years of age (18.6%) had established PPSV23 indications; adding asthma and smoking to the list of indications increased the high-risk population to 71.6 million people (37.9%). Overall, 26.1% of people with established indications for PPSV23 and 17.4% of people with any indication (those previously established, as well as asthma and smoking) had received the vaccine; overall coverage among persons 50-64 years of age was significantly higher than that among persons 18-49 years of age (34.6% vs. 16.7%; P < 0.001) and for all specific indications except cancer. For persons who had asthma or who smoked but had no other indications, rates of coverage were 12.3% and 8.5%, respectively. In persons who had established indications, being older, white, and unemployed and having more physician visits, a prior hospitalization, a regular physician, and health insurance were independently associated with PPSV23 receipt. PPSV23 uptake varies substantially by age and indication but remains low overall, with approximately 59 million unvaccinated high-risk working-age adults. Effective strategies to increase pneumococcal vaccination coverage among at-risk groups are needed.
No preview · Article · Mar 2012 · American journal of epidemiology
[Show abstract][Hide abstract]ABSTRACT: The cost-effectiveness of 13-valent pneumococcal conjugate vaccine (PCV13) compared with 23-valent pneumococcal polysaccharide vaccine (PPSV23) among US adults is unclear.
To estimate the cost-effectiveness of PCV13 vaccination strategies in adults.
A Markov state-transition model, lifetime time horizon, societal perspective. Simulations were performed in hypothetical cohorts of US 50-year-olds. Vaccination strategies and effectiveness estimates were developed by a Delphi expert panel; indirect (herd immunity) effects resulting from childhood PCV13 vaccination were extrapolated based on observed PCV7 effects. Data sources for model parameters included Centers for Disease Control and Prevention Active Bacterial Core surveillance, National Hospital Discharge Survey and Nationwide Inpatient Sample data, and the National Health Interview Survey.
Pneumococcal disease cases prevented and incremental costs per quality-adjusted life-year (QALY) gained.
In the base case scenario, administration of PCV13 as a substitute for PPSV23 in current recommendations (ie, vaccination at age 65 years and at younger ages if comorbidities are present) cost $28,900 per QALY gained compared with no vaccination and was more cost-effective than the currently recommended PPSV23 strategy. Routine PCV13 at ages 50 and 65 years cost $45,100 per QALY compared with PCV13 substituted in current recommendations. Adding PPSV23 at age 75 years to PCV13 at ages 50 and 65 years gained 0.00002 QALYs, costing $496,000 per QALY gained. Results were robust in sensitivity analyses and alternative scenarios, except when low PCV13 effectiveness against nonbacteremic pneumococcal pneumonia was assumed or when greater childhood vaccination indirect effects were modeled. In these cases, PPSV23 as currently recommended was favored.
Overall, PCV13 vaccination was favored compared with PPSV23, but the analysis was sensitive to assumptions about PCV13 effectiveness against nonbacteremic pneumococcal pneumonia and the magnitude of potential indirect effects from childhood PCV13 on pneumococcal serotype distribution.
No preview · Article · Feb 2012 · JAMA The Journal of the American Medical Association
[Show abstract][Hide abstract]ABSTRACT: Sindbis virus (SINV) is an arthropod-borne alphavirus that causes rash and arthritis. In Finland, epidemics occur cyclically, but factors associated with clinical SINV infection are largely unknown. We conducted a population-based case-control study during the epidemic year 2002.
SINV cases were serologically confirmed and reported to the National Infectious Disease Registry. Five control subjects, matched for age, sex, and residence, were selected from the National Population Information System. Data were collected using a self-administered mail survey. Conditional logistic regression models were used to identify independent risk factors; missing data were addressed using Bayesian full-likelihood modeling.
A total of 337 case patients (58% female; age range, 1-94 y) and 934 control subjects were enrolled. Reported exposure to mosquito bites (matched odds ratio [mOR], 16.7; 95% confidence interval [CI], 9.1-33.4) and spending time in woods or marshland (mOR, 1.8; 95% CI, 1.3-2.5) were independently associated with SINV infection in the multivariable model. The population-attributable risk for mosquito bites was 87.2%. There were dose-response relations for increased number of insect bites (mOR, 23.8-72.5) and increased time spent in woods or marshland (mOR, 1.3-2.2).
Educating the public in endemic areas to avoid mosquito exposure and use protective measures remain important prevention measures for SINV infection.
Full-text · Article · Aug 2011 · The Journal of Infectious Diseases
[Show abstract][Hide abstract]ABSTRACT: Alaska Native and some American Indian (AI/AN) populations suffer disproportionately high rates of invasive pneumococcal disease (IPD) in both the pediatric and adult populations compared to the general U.S. population. Two pneumococcal vaccines are currently available in the U.S.: a 23-valent pneumococcal polysaccharide vaccine (PPSV23), available since 1983 and recommended for the elderly and those over 2 years of age with underlying medical conditions, and a 13-valent pneumococcal conjugate vaccine (PCV13), used in the routine infant immunization schedule since 2010. The U.S. Advisory Committee on Immunization Practice (ACIP) previously recommended use of PPSV23 for persons living in special environments or social settings, including AN and certain AI persons 2-64 years of age, on the basis of higher disease rates. The recommendation for routine PPSV23 use among AI/AN persons <65 years of age, regardless of underlying conditions, was removed in 2008, although the option for use among those 50-64 years of age living in areas with high pneumococcal disease rates was maintained. The rationale for the revised recommendations lay in the recognition that much of the excess disease burden occurs among those with an existing medical indication for PPSV23. Other considerations for the change were the potential risks of giving multiple PPSV23 doses and the considerable heterogeneity in pneumococcal disease risk among American Indian populations requiring a more tailored approach to local recommendations based on local epidemiology.
[Show abstract][Hide abstract]ABSTRACT: Although recent reports suggest that the incidence of parapneumonic empyema has increased in several regions of the USA, national trends in disease burden are unknown. National trends in the incidence of parapneumonic empyema hospitalisations and changes in empyema by associated pathogens were examined.
National hospitalisation data (1996-2008) were analysed and rates estimated using census estimates as denominators. Incidence rate ratios (IRR) compared 2008 with 1996 rates. Discharge diagnosis codes were used to characterise pathogens associated with empyema hospitalisations.
Overall, national parapneumonic empyema-related hospitalisation rates increased from 3.04 per 100,000 in 1996 to 5.98 per 100,000 in 2008, a 2.0-fold increase (95% CI 1.8 to 2.1). The increases were observed among children (IRR 1.9 (95% CI 1.4 to 2.7)) and adults aged 18-39, 40-64 and ≥65 years (IRR 1.8 (95% CI 1.5 to 2.1), 2.0 (95% CI 1.6 to 3.1) and 1.7 (95% CI 1.5 to 2.0), respectively). Overall, pneumococcal empyema rates remained relatively stable in all age groups whereas streptococcal- (non-pneumococcal) and staphylococcal-related empyema rates increased 1.9-fold and 3.3-fold, respectively, with consistent increases across age groups. The overall in-hospital case fatality ratio for parapneumonic empyema-related hospitalisations was 8.0% (95% CI 6.4% to 9.5%) in 1996 and 7.2% (95% CI 6.3% to 8.1%) in 2008 (p=0.395). Of the empyemas where study pathogens were listed (37.6%), staphylococcal-related empyema had the largest absolute increases across age groups and was associated with longer hospital stay and higher in-hospital mortality than other empyemas.
Although parapneumonic empyema-related hospitalisations remained relatively rare, they increased substantially during the study period. A number of pathogens, especially staphylococcus, contributed to this increase.