Aid workers fear a shortage of fresh water in Papua New Guinea's East Sepik could worsen a cholera outbreak there.
Cholera is transmitted by a bacteria often found in contaminated water and the World Health Organisation has confirmed that the main river, the Sepik, is carrying the bacteria.
More than 600 people have been infected and about 16 people have died since cholera appeared in the province four months ago.
The Sepik Programme Manager for the aid organisation Oxfam, Andrew Rankin, says other possible fresh water sources have dried up.
"There has been a lack of rain in the last few months, so although Oxfam has been looking at options such as setting up temporary water catchments as a short term fix to give more fresh water sources, that's a problem if there's a lack of rain to be able to actually start this process."
Andrew Rankin of Oxfam.
Outbreaks in two other provinces, Madang and Morobe, are continuing.