Seasonal and interannual cycles of endemic cholera in Bengal 1891-1940 in relation to climate and geography

摘要: Unravelling the epidemiology of cholera has been one most elusive problems in tropical medicine. The early contest between ‘contagionists’ and ‘localists’ last century finds a modern equivalent on-going debate on whether significant environmental determinants. This study investigates role climate geography seasonality interannual variations cholera, using historical mortality data 1891 1940 from 24 districts Bengal. coastal exhibit bi-annual seasonal cycle, as previously described for this region, but with dominant peak spring. Spring mortality, particularly shows correlations (r=0.50, p 0.001) sea temperatures Pacific (an El Nino index) cholera’s spring deaths, at frequency approximately 1 /4.2 years power spectrum, support influence climatic forcing. Cholera’s winter peak, further away estuary, appears less consistently associated water Bay Bengal, accounts variation geographical spread differences our results suggest possibility different aquatic reservoirs pathogen. As temperature can only explain part variability is similar to that other parameters, studies elucidate causal pathways are warranted. Here, we provide climatological hypothesis factors important dynamics endemic cholera.