Water-borne diseases can occur through poor hygiene due to water shortages. Viral and bacterial contamination of shellfish can occur with warmer waters. Some water-borne diseases that have increased with a change in climate include Cryptosporadia, Giardia, and Cholera. Vibrio cholerae causes cholera, a disease in which the symptoms are voluminous water stool output and thus dehydration. People infected with cholera become lethargic with sunken eyes and cheeks and dry mucous membranes.
Urine flow is decreased or absent.
With warmer waters a chain reaction begins that increases the incidences of cholera. Warming of the seas surface temperature can increase algae and plankton blooms. Copepods, or zooplankton, feed on algae and can serve as reservoirs for Vibrio cholerae . Global warming can increase coastal areas susceptibility to this disease. With warmer temperatures, heat-related deaths and illnesses are expected to rise.