Aid organisations are buying in more supplies for Solomon Islands in the aftermath of deadly flooding but it may not arrive for weeks.
Up to 10,000 people are still living in evacuation centres since major flooding on 3 April which left more than 20 dead. Since then Pacific nation has been rattled by strong earthquakes, the largest at 7.6 magnitude on Sunday.
Lack of sanitation in evacuation centres is beginning to cause problems and outbreaks of disease are starting to occur.
World Vision country director Andrew Catford told Radio New Zealand's Morning Report programme 500 children in the centres have diarrhoea and there have also been outbreaks of conjuctivitus.Oxfam said there also cases of malaria and dengue fever and there were some concerns about diseases spread through an influx in the population of rats.
Save the Children emergencies manager in Honiara, Graham Kenna, said most of the centres are based in schools and in one, housing 2000 people, there were only two working toilets.
Mr Kenna said about 40 percent of the aid supplies needed as arrived or is on the way and aid organisations have started to buy in more provisions.
"That's coming from a long way away and may not be here for four or five weeks, so that is a worry."
The Red Cross said it was visiting affected communities and will distribute supplies such as shelter and hygiene kits based on what is found.
New Zealand medical workers fly to the Solomon Islands on Tuesday evening to deal with increasing levels of disease since floods devastated the nation. The Ministry of Health said the 10 medical staff workers will help bolster staff numbers at the main hospital in Honiara.
New Zealand will also provide a Bailey bridge between the airport and the centre of the capital.