Cholera outbreaks 'not caused' by warmer seas - AlertNet

[SANTIAGO] The conclusion that cholera outbreaks are linked to global warming has been challenged by a study that has found that warmer sea temperatures that correlate with the outbreaks do not cause them.

Outbreaks follow the blooming of phytoplankton which is associated with warmer seas in the Bay of Bengal — but these blooms are driven by river discharges rather than warmer seas, say authors of the study, published last week (3 August) in the American Journal of Tropical Medicine and Hygiene.

Previous studies have suggested that periods of warmer sea temperature could be one of the conditions for promoting the disease, such as in the recent outbreak in Haiti, and that such knowledge could help set up an early warning system.

But it was not clear why this happens, as phytoplankton, microscopic plants that feed tiny crustaceans to which Vibrio cholerae bacteria attach, thrive in cold, not warm, water.