Prevalence of HBV and HCV infections, Bhutan, 2017: Progress and next steps.

BACKGROUND: Bhutan is committed to eliminating hepatitis B and hepatitis C, though recent baseline estimates of disease burden in the general population are unknown. In 2017, we carried out a biomarker survey in the general population to estimate the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) biomarkers to evaluate the impact of immunization and guide further efforts. METHODS: In 2017, a cross-sectional, population-based, three-stage cluster survey was undertaken of the general population (1-17 and 20+ years of age). We visited households, collected blood specimens and administered a standard questionnaire. Specimens were collected for hepatitis B surface antigen (HBsAg) and hepatitis C virus antibody (anti-HCV) testing. We calculated prevalence of infection and selected characteristics, along with confidence intervals (CIs). RESULTS: Of 1372 individuals approached, 1358 (99%) participated. Of those, 1321 (97%) had a specimen tested for HBsAg, and among 1173 enrolled individuals 5 years of age or older, 1150 (98%) individuals were tested for anti-HCV. The prevalence of HBsAg was 2.0% in 775 persons 20 years of age or older (95% CI: 1.0-4.0) and 0.5% in 546 persons 1-17 years of age (95% CI: 0.1-1.8). The prevalence of anti-HCV was 0.3% (95% CI: 0.1-0.8) among persons ≥5 years. CONCLUSIONS: Universal hepatitis B immunization of infants has resulted in a low prevalence of chronic HBV infection in persons 1-17 years of age and the prevalence of anti-HCV is low among persons aged ≥5 years. Efforts should continue to reach high coverage of the timely birth dose along with completion of the hepatitis B vaccine series. To reduce the chronic liver disease burden among adults, HBV and HCV testing and treatment as indicated might be restricted to pregnant women, blood donors, individuals with chronic liver diseases, and other groups with history of high-risk exposures.

Immunity to polio, measles and rubella in women of child-bearing age and estimated congenital rubella syndrome incidence, Cambodia, 2012.

Significant gaps in immunity to polio, measles, and rubella may exist in adults in Cambodia and threaten vaccine-preventable disease (VPD) elimination and control goals, despite high childhood vaccination coverage. We conducted a nationwide serological survey during November-December 2012 of 2154 women aged 15-39 years to assess immunity to polio, measles, and rubella and to estimate congenital rubella syndrome (CRS) incidence. Measles and rubella antibodies were detected by IgG ELISA and polio antibodies by microneutralization testing. Age-structured catalytic models were fitted to rubella serological data to predict CRS cases. Overall, 29.8% of women lacked immunity to at least one poliovirus (PV); seroprevalence to PV1, PV2 and PV3 was 85.9%, 93.4% and 83.3%, respectively. Rubella and measles antibody seroprevalence was 73.3% and 95.9%, respectively. In the 15-19 years age group, 48.2% [95% confidence interval (CI) 42.4-54.1] were susceptible to either PV1 or PV3, and 40.3% (95% CI 33.0-47.5) to rubella virus. Based on rubella antibody seroprevalence, we estimate that >600 infants are born with CRS in Cambodia annually. Significant numbers of Cambodian women are still susceptible to polio and rubella, especially those aged 15-19 years, emphasizing the need to include adults in VPD surveillance and a potential role for vaccination strategies targeted at adults.

Surveillance during an era of rapidly changing poliovirus epidemiology in India: the role of one vs. two stool specimens in poliovirus detection, 2000-2010.

Since 2004, efforts to improve poliovirus detection have significantly increased the volume of specimen testing from acute flaccid paralysis (AFP) patients in India. One option to decrease collection and testing burden would be collecting only a single stool specimen instead of two. We investigated stool specimen sensitivity for poliovirus detection in India to estimate the contribution of the second specimen. We reviewed poliovirus isolation data for 303984 children aged <15 years with AFP during 2000-2010. Using maximum-likelihood estimation, we determined specimen sensitivity of each stool specimen, combined sensitivity of both specimens, and sensitivity added by the second specimen. Of 5184 AFP patients with poliovirus isolates, 382 (7.4%) were identified only by the second specimen. Sensitivity was 91.4% for the first specimen and 84.5% for the second specimen; the second specimen added 7.3% sensitivity, giving a combined sensitivity of 98.7%. Combined sensitivity declined, and added sensitivity increased, as the time from paralysis onset to stool collection increased (P = 0.032). The sensitivity added by the second specimen is important to detect the last chains of poliovirus transmission and to achieve certification of polio eradication. For sensitive surveillance, two stool specimens should continue to be collected from each AFP patient in India.

Identification of serologic markers for school-aged children with congenital rubella syndrone

BACKGROUND: Congenital rubella syndrome (CRS) case identification is challenging in older children since laboratory markers of congenital rubella virus (RUBV) infection do not persist beyond age 12 months. METHODS: We enrolled children with CRS born between 1998 and 2003 and compared their immune responses to RUBV with those of their mothers and a group of similarly aged children without CRS. Demographic data and sera were collected. Sera were tested for anti-RUBV immunoglobulin G (IgG), IgG avidity, and IgG response to the 3 viral structural proteins (E1, E2, and C), reflected by immunoblot fluorescent signals. RESULTS: We enrolled 32 children with CRS, 31 mothers, and 62 children without CRS. The immunoblot signal strength to C and the ratio of the C signal to the RUBV-specific IgG concentration were higher (P < .029 for both) and the ratio of the E1 signal to the RUBV-specific IgG concentration lower (P = .001) in children with CRS, compared with their mothers. Compared with children without CRS, children with CRS had more RUBV-specific IgG (P < .001), a stronger C signal (P < .001), and a stronger E2 signal (P ≤ .001). Two classification rules for children with versus children without CRS gave 100% specificity with >65% sensitivity. CONCLUSIONS: This study was the first to establish classification rules for identifying CRS in school-aged children, using laboratory biomarkers. These biomarkers should allow improved burden of disease estimates and monitoring of CRS control programs. Published by Oxford University Press on behalf of the Infectious Diseases Society of America 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Microbiologic effectiveness of boiling and safe water storage in South Sulawesi, Indonesia.

In Indonesia, where diarrhea remains a major cause of mortality among children <5 years, the government promotes boiling of drinking water. We assessed the impact of boiling on water quality in South Sulawesi. We surveyed randomly selected households with at least one child <5 years old in two rural districts and tested source and stored water samples for Escherichia coli contamination. Among 242 households, 96% of source and 51% of stored water samples yielded E. coli. Unboiled water samples, obtained from 15% of households, were more likely to yield E. coli than boiled samples [prevalence ratios (PR) = 2.0, 95% confidence interval (CI) 1.7-2.5]. Water stored in wide-mouthed (PR = 1.4, 95% CI = 1.1-1.8) or uncovered (PR = 1.8, 95% CI = 1.3-2.4) containers, or observed to be touched by the respondent's hands (PR = 1.6, 95% CI = 1.3-2.1) was more likely to yield E. coli. A multivariable model showed that households that did not boil water were more likely to have contaminated stored water than households that did boil water (PR = 1.9, 95% CI = 1.5-2.3). Although this study demonstrated the effectiveness of boiling in reducing contamination, overall impact on water quality was suboptimal. Future studies are needed to identify factors behind the success of boiling water in Indonesia to inform efforts to scale up other effective water treatment practices.

Multistate outbreak of Escherichia coli O157:H7 infections associated with a national fast-food chain, 2006: a study incorporating epidemiological and food source traceback results.

A multistate outbreak of Escherichia coli O157:H7 infections occurred in the USA in November-December 2006 in patrons of restaurant chain A. We identified 77 cases with chain A exposure in four states - Delaware, New Jersey, New York, and Pennsylvania. Fifty-one (66%) patients were hospitalized, and seven (9%) developed haemolytic uraemic syndrome; none died. In a matched analysis controlling for age in 31 cases and 55 controls, illness was associated with consumption of shredded iceberg lettuce [matched odds ratio (mOR) 8·0, 95% confidence interval (CI) 1·1-348·1] and shredded cheddar cheese (mOR 6·2, CI 1·7-33·7). Lettuce, an uncooked ingredient, was more commonly consumed (97% of patients) than cheddar cheese (84%) and a single source supplied all affected restaurants. A single source of cheese could not explain the regional distribution of outbreak cases. The outbreak highlights challenges in conducting rapid multistate investigations and the importance of incorporating epidemiological study results with other investigative findings.

On the use of zero-inflated and hurdle models for modeling vaccine adverse event count data.

We compared several modeling strategies for vaccine adverse event count data in which the data are characterized by excess zeroes and heteroskedasticity. Count data are routinely modeled using Poisson and Negative Binomial (NB) regression but zero-inflated and hurdle models may be advantageous in this setting. Here we compared the fit of the Poisson, Negative Binomial (NB), zero-inflated Poisson (ZIP), zero-inflated Negative Binomial (ZINB), Poisson Hurdle (PH), and Negative Binomial Hurdle (NBH) models. In general, for public health studies, we may conceptualize zero-inflated models as allowing zeroes to arise from at-risk and not-at-risk populations. In contrast, hurdle models may be conceptualized as having zeroes only from an at-risk population. Our results illustrate, for our data, that the ZINB and NBH models are preferred but these models are indistinguishable with respect to fit. Choosing between the zero-inflated and hurdle modeling framework, assuming Poisson and NB models are inadequate because of excess zeroes, should generally be based on the study design and purpose. If the study's purpose is inference then modeling framework should be considered. For example, if the study design leads to count endpoints with both structural and sample zeroes then generally the zero-inflated modeling framework is more appropriate, while in contrast, if the endpoint of interest, by design, only exhibits sample zeroes (e.g., at-risk participants) then the hurdle model framework is generally preferred. Conversely, if the study's primary purpose it is to develop a prediction model then both the zero-inflated and hurdle modeling frameworks should be adequate.

Incidence of invasive aspergillosis following hematopoietic stem cell and solid organ transplantation: interim results of a prospective multicenter surveillance program.

The incidence of invasive aspergillosis was estimated among 4621 hematopoietic stem cell transplants (HSCT) and 4110 solid organ transplants (SOT) at 19 sites dispersed throughout the United States, during a 22 month period from 1 March 2001 through 31 December 2002. Cases were identified using the consensus definitions for proven and probable infection developed by the Invasive Fungal Infections Cooperative Group of the European Organization for Research and Treatment of Cancer and the Mycoses Study Group of the National Institute of Allergy and Infectious Diseases. The cumulative incidence (CI) of aspergillosis was calculated for the first episode of the infection that occurred within the specified time period after transplantation. To obtain an aggregate CI for each type of transplant, data from participating sites were weighted according to the proportion of transplants followed-up for specified time periods (four and 12 months for HSCT; six and 12 months for SOT). The aggregate CI of aspergillosis at 12 months was 0.5% after autologous HSCT, 2.3% after allogeneic HSCT from an HLA-matched related donor, 3.2% after transplantation from an HLA-mismatched related donor, and 3.9% after transplantation from an unrelated donor. The aggregate CI at 12 months was similar following myeloablative or non-myeloablative conditioning before allogeneic HSCT (3.1 vs. 3.3%). After HSCT, mortality at 3 months following diagnosis of aspergillosis ranged from 53.8% of autologous transplants to 84.6% of unrelated-donor transplants. The aggregate CI of aspergillosis at 12 months was 2.4% after lung transplantation, 0.8% after heart transplantation, 0.3% after liver transplantation, and 0.1% after kidney transplantation. After SOT, mortality at three months after diagnosis of aspergillosis ranged from 20% for lung transplants to 66.7% for heart and kidney transplants. The Aspergillus spp. associated with infections after HSCT included A. fumigatus (56%), A. flavus (18.7%), A. terreus (16%), A. niger (8%), and A. versicolor (1.3%). Those associated with infections after SOT included A. fumigatus (76.4%), A. flavus (11.8%), and A. terreus (11.8%). In conclusion, we found that invasive aspergillosis is an uncommon complication of HSCT and SOT, but one that continues to be associated with poor outcomes. Our CI figures are lower compared to those of previous reports. The reasons for this are unclear, but may be related to changes in transplantation practices, diagnostic methods, and supportive care.

Recognition of pallor associated with severe anaemia by primary caregivers in western Kenya.

OBJECTIVES: To explore which pallor signs and symptoms of severe anaemia could be recognized by primary caregivers following minimal instructions. METHODS: Data from three community-based cross-sectional surveys were used. Test characteristics to predict haemoglobin (Hb) concentrations < 5 and < 7 g/dl were compared for different combinations of pallor signs (eyelid, tongue, palmar and nailbed) and symptoms. RESULTS: Pallor signs and haemoglobin levels were available for 3782 children under 5 years of age from 2609 households. Comparisons of the sensitivity and specificity at a range of haemoglobin cut-offs showed that Hb < 5 g/dl was associated with the greatest combined sensitivity and specificity for pallor at any anatomical site (sensitivity = 75.6%, specificity = 63.0%, Youden index = 38.6). Higher or lower haemoglobin cut-offs resulted in more children being misclassified. Similar results were obtained for all individual pallor sites. Combining a history of soil eating with pallor at any site improved the sensitivity (87.8%) to detect Hb < 5 g/dl with a smaller reduction in specificity (53.3%; Youden index 41.1). Other combinations including respiratory signs or poor feeding resulted in lower accuracy. CONCLUSION: Primary caregivers can recognize severe anaemia (Hb < 5 g/dl) in their children, but only with moderate accuracy. Soil eating should be considered as an additional indicator of severe anaemia. The effect of training caretakers to improve recognition of severe anaemia and care-seeking behaviour at the household level should be assessed in prospective community-based studies.