27 research outputs found
Pertussis infection in fully vaccinated children in day-care centers, Israel.
We tested 46 fully vaccinated children in two day-care centers in Israel who were exposed to a fatal case of pertussis infection. Only two of five children who tested positive for Bordetella pertussis met the World Health Organization's case definition for pertussis. Vaccinated children may be asymptomatic reservoirs for infection
Estimating the Duration of Pertussis Immunity Using Epidemiological Signatures
Case notifications of pertussis have shown an increase in a number of countries with high rates of routine pediatric immunization. This has led to significant public health concerns over a possible pertussis re-emergence. A leading proposed explanation for the observed increase in incidence is the loss of immunity to pertussis, which is known to occur after both natural infection and vaccination. Little is known, however, about the typical duration of immunity and its epidemiological implications. Here, we analyze a simple mathematical model, exploring specifically the inter-epidemic period and fade-out frequency. These predictions are then contrasted with detailed incidence data for England and Wales. We find model output to be most sensitive to assumptions concerning naturally acquired immunity, which allows us to estimate the average duration of immunity. Our results support a period of natural immunity that is, on average, long-lasting (at least 30 years) but inherently variable
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The ameliorating effect of lumbar puncture in viral meningitis
To test the hypothesis that lumbar puncture in viral meningitis results in symptomatic improvement, a group of 48 children was studied. Twenty-six patients had proved aseptic meningitis, and 22 had infections outside the central nervous system. Before and after lumbar puncture each subject was repeatedly scored for symptoms independently by the attending pediatrician and a parent. Marked symptomatic improvement in children with meningitis was demonstrated following lumbar puncture, while no significant change was demonstrated in the control group. The mechanism underlying this improvement is not clear; however, we consider a number of possible explanations
Evaluating the utility of self-reported questionnaire data to screen for dysglycemia in young adults: Findings from the US National Health and Nutrition Examination Survey
Dysglycemia, including prediabetes and type 2 diabetes, is dangerous and widespread. Yet, the condition is transiently reversible and sequelae preventable, prompting the use of prediction algorithms to quickly assess dysglycemia status through self-reported data. However, as current algorithms have largely been developed in older populations, their application to younger adults is uncertain considering associations between risk factors and dysglycemia vary by age. We sought to identify sex-specific predictors of current dysglycemia among young adults and evaluate their ability to screen for prediabetes and undiagnosed diabetes. We analyzed 2005–2014 data from the National Health and Nutrition Examination Survey for 3251 participants aged 20–39, who completed an oral glucose tolerance test (OGTT), had not been diagnosed with diabetes, and, for females, were not pregnant. Sex-specific stepwise logistic models were fit with predictors identified from univariate analyses. Risk scores were developed using adjusted odds ratios and model performance was assessed using area under the curve (AUC) measures. The OGTT identified 906 (27.9%) and 78 (2.4%) participants with prediabetes or undiagnosed diabetes, respectively. Predictors of dysglycemia status for males were BMI, age, race, and first-degree family history of diabetes, and, in addition to those, education, delivered baby weight, waist circumference, and vigorous physical activity for females. Our male- and female-specific models demonstrated improved validity to assess dysglycemia presence among young adults relative to the widely-used American Diabetes Association test (AUC = 0.69 vs. 0.61; 0.92 vs. 0.71, respectively). Thus, age-specific scoring algorithms employing questionnaire data show promise and are effective in identifying dysglycemia among young adults
An outbreak of pertussis among young Israeli soldiers.
In winter 2001, an outbreak of pertussis involving an estimated 75 people occurred among soldiers serving in an infantry regiment of the Israeli Defense Forces (IDF). Nasopharyngeal swabs were obtained from patients and contacts for culture and PCR. Serum samples were obtained and assayed by ELISA for the presence of IgA, IgM and IgG antibodies to a lysate antigen of Bordetella pertussis. The calculated attack rate was 21% based on clinical signs alone (cough lasting 30 days or longer) and 9.5% based on clinical signs with laboratory confirmation (by PCR, IgA or IgM). A high carriage rate was observed; 20% of the asymptomatic and previously symptomatic subjects were PCR-positive for B. pertussis. These findings emphasize the importance of B. pertussis as a causative agent of epidemic respiratory infections in young adults and reveal the occurrence of a significant proportion of pertussis transient carriers during an outbreak of the disease