A team of Spanish, US and Bangladeshi researchers have shown that the relationship between climatic variation on cholera epidemics has become stronger over the past few years. The same scientists had already provided evidence to show that a relationship between climatic variation associated with the El Niño-Southern oscillation (ENSO) and the outbreak of cholera epidemics exists. The new research indicates that the relationship has become stronger as levels of ENSO have intensified on account of climate change. Dr Xavier Rodó, coordinator of the research group believes that this study is 'one of the first demonstrations of the possible effects of climatic change on the incidence of infectious diseases.' The study has led to the development of a new statistical tool, evidence from which has shown that the correlation between cholera and climate is three times as strong as previously believed. The study also resulted in a predictive model, which could be used to plan health measures in the areas affected by cholera. Since the end of the 1970s, warm periods induced by ENSO have become progressively more intense. In South east Asia, the regional rise in temperature as a result of climatic change and ENSO can lead to the proliferation of bacteria that inhabit salty waters and thrive at high temperatures. These findings, together with the fact that people tend to have more contact with water during hot periods, may explain the higher correlation between ENSO and cholera in recent decades.