Arsenic exposure through drinking water has generated excess adult mortality after 20-30 years of exposure.

BackgroundThe objective of this population-based case–referent study in Matlab, Bangladesh, was to assess the susceptibility to arsenic-induced skin lesions by age and sex, in a population drinking water from As-contaminated tube wells.MethodsIdentification of As-related skin lesions was carried out in three steps: a) screening of the entire population > 4 years of age (n = 166,934) by trained field teams; b) diagnosis of suspected As-related cases by physicians; and c) confirmation by experts based on physicians’ records and photographs. A total of 504 cases with skin lesions were confirmed. We randomly selected 2,201 referents from the Matlab health and demographic surveillance system; 1,955 were eligible, and 1,830 (94%) were available for participation in the study. Individual history of As exposure was based on information obtained during interviews and included all drinking-water sources used since 1970 and concentrations of As (assessed by atomic absorption spectrophotometry) in all the tube wells used.ResultsCases had been exposed to As more than referents (average exposure since 1970: male cases, 200 μg/L; female cases, 211 μg/L; male referents, 143 μg/L; female referents, 155 μg/L). We found a dose–response relationship for both sexes (p < 0.001) and increased risk with increasing socioeconomic status. Males had a higher risk of obtaining skin lesions than females (odds ratio 10.9 vs. 5.78) in the highest average exposure quintile (p = 0.005). Start of As exposure (cumulative exposure) before 1 year of age was not associated with higher risk of obtaining skin lesions compared to start of As exposure later in life.ConclusionsThe results demonstrate that males are more susceptible than females to develop skin lesions when exposed to As in water from tube wells.

SummaryBackgroundThe rates of influenza illness and associated complications are high among children in Bangladesh. We assessed the clinical efficacy and safety of a Russian-backbone live attenuated influenza vaccine (LAIV) at two field sites in Bangladesh.MethodsBetween Feb 27 and April 9, 2013, children aged 2–4 years in urban Kamalapur and rural Matlab, Bangladesh, were randomly assigned in a 2:1 ratio, according to a computer-generated schedule, to receive one intranasal dose of LAIV or placebo. After vaccination, we monitored children in weekly home visits until Dec 31, 2013, with study clinic surveillance for influenza illness. The primary outcome was symptomatic, laboratory-confirmed influenza illness due to vaccine-matched strains. Analysis was per protocol. The trial is registered with ClinicalTrials.gov, number NCT01797029.FindingsOf 1761 children enrolled, 1174 received LAIV and 587 received placebo. Laboratory-confirmed influenza illness due to vaccine-matched strains was seen in 93 (15·8%) children in the placebo group and 79 (6·7%) in the LAIV group. Vaccine efficacy of LAIV for vaccine-matched strains was 57·5% (95% CI 43·6–68·0). The vaccine was well tolerated, and adverse events were balanced between the groups. The most frequent adverse events were tachypnoea (n=86 in the LAIV group and n=54 in the placebo group), cough (n=73 and n=43), and runny nose (n=68 and n=39), most of which were mild.InterpretationThis single-dose Russian-backbone LAIV was safe and efficacious at preventing symptomatic laboratory-confirmed influenza illness due to vaccine-matched strains. LAIV programmes might reduce the burden of influenza illness in Bangladesh.FundingThe Bill & Melinda Gates Foundation.

Background Epidemiologic research suggests that increased cancer risk due to chronic arsenic exposure persists for several decades even after the exposure has terminated. Observational studies suggest antioxidants exert a protective effect on arsenical skin lesions and cancers among those chronically exposed to arsenic through drinking water. This study reports on the design, methods, and baseline analyses from the Bangladesh Vitamin E and Selenium Trial (BEST), a population based chemoprevention study conducted among adults in Bangladesh with visible arsenic toxicity. Materials and methods BEST is a 2×2 full factorial double-blind randomized controlled trial of 7,000 adults having manifest arsenical skin lesions evaluating the efficacy of 6-year supplementation with alpha-tocopherol (100 mg daily) and L-selenomethionine (200 μg daily) for the prevention of non-melanoma skin cancer. Results In cross-sectional analyses, we observed significant associations of skin lesion severity with male sex (female prevalence odds ratio (POR)=0.87; 95% CI=0.79–0.96), older age (aged 36–45 POR=1.27; 95% CI=1.13–1.42; aged 46–55 POR=1.44; 95% CI=1.27–1.64; and aged 56–65 POR=1.50; 95% CI=1.26–1.78 compared to aged 25–35), hypertension (POR=1.29; 95% CI=1.08–1.55), diabetes (POR=2.13; 95% CI=1.32–3.46), asthma (POR=1.55; 95% CI=1.03–2.32), and peptic ulcer disease (POR=1.20; 95% CI=1.07–1.35). Conclusions We report novel associations between arsenical skin lesions with several common chronic diseases. With the rapidly increasing burden of preventable cancers in developing countries, efficient and feasible chemoprevention study designs and approaches, such as employed in BEST, may prove both timely and potentially beneficial in conceiving cancer chemoprevention trials in Bangladesh and beyond.

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