The World Health Organisation says the problem of water-borne diseases is far worse for low-lying small Pacific Island states, who remain highly susceptible to the effect of climate change.
The WHO attended this month's Asia Pacific Water Summit that was called to help solve the region's water and sanitation problems.
Steve Iddings, the environmental engineer for the WHO's Pacific office in Fiji, says water sources in countries like Tuvalu, Kiribati and the Marshall Islands are more vulnerable to salt water, variable weather patterns and increased population demands.
He says industries, like tourism, also increases the risk of pollution.
Mr Iddings says the WHO is working with the South Pacific Applied Geoscience commission and governments to try to reduce the effects of pollution, and better manage clean water sources.
"The theme of water and climate were very important for health because of the incidences of diarrhoeal diseases and includes even cholera which does occur in the Pacific as well as to other diseases related to water and sanitation."
Steven Iddings says although efforts are focussed on prevention measures, the situation for island states remains critical.