It has long been known that cholera outbreaks can be initiated when Vibrio cholerae, the bacterium that causes cholera, is present in drinking water in sufficient numbers to constitute an infective dose, if ingested by humans. Outbreaks associated with drinking or bathing in unpurified river or brackish water may directly or indirectly depend on such conditions as water temperature, nutrient concentration, and plankton production that may be favorable for growth and reproduction of the bacterium. Although these environmental parameters have routinely been measured by using water samples collected aboard research ships, the available data sets are sparse and infrequent. Furthermore, shipboard data acquisition is both expensive and time-consuming. Interpolation to regional scales can also be problematic. Although the bacterium, V. cholerae, cannot be sensed directly, remotely sensed data can be used to infer its presence. In the study reported here, satellite data were used to monitor the timing and spread of cholera. Public domain remote sensing data for the Bay of Bengal were compared directly with cholera case data collected in Bangladesh from 1992-1995. The remote sensing data included sea surface temperature and sea surface height. It was discovered that sea surface temperature shows an annual cycle similar to the cholera case data. Sea surface height may be an indicator of incursion of planktonladen water inland, e.g., tidal rivers, because it was also found to be correlated with cholera outbreaks. The extensive studies accomplished during the past 25 years, confirming the hypothesis that V. cholerae is autochthonous to the aquatic environment and is a commensal of zooplankton, i.e., copepods, when combined with the findings of the satellite data analyses, provide strong evidence that cholera epidemics are climate-linked. C holera is an acute intestinal disease caused by the bacterium Vibrio cholerae. The disease frequently strikes in the form of severe epidemics, in Bangladesh and other developing countries, that occur with a more or less annual periodicity. The seventh pandemic of cholera started in 1961 and currently affects six continents (1, 2). Cholera is one of a number of infectious diseases that appears to be influenced by climatic changes (2-4). The study reported here was undertaken to gather data needed to develop a cholera prediction model that would monitor ocean parameters, based on remote sensing (RS) data, and provide early warning of conditions associated with cholera outbreaks. Therefore, the focus of the study was on public domain data sources to determine what, if any, relationship could be detected between remotely sensed ocean parameters and cholera case data for Bangladesh. These relationships are important in model development. When such a model for Bangladesh is extended to the global scale, it can serve as an early warning system for cholera, enabling an effective deployment of resources to minimize or prevent cholera epidemics in cholera endemic regions.Ideally, to verify the sequ...

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