CANBERRA, Jan 15 (Reuters) - Widespread destruction caused by a tropical cyclone that hit the South Pacific island nation of Tonga last week is raising fears of a disease outbreak in the island kingdom.
Tropical Cyclone Ian, a category-five cyclone, appears to have destroyed up to 90 percent of homes on the northern Ha'apai Islands, which are home to about 8,000 people, the regional governor said on Wednesday.
An emergency response team from British aid group Oxfam said the outer islands of Foa, Ha'ano and Mo'unga'one in the Ha'apai Islands chain had been 90 percent destroyed. Pangai, the capital of Ha'apai, suffered about 80 percent damage, it said.
International aid organisations, which have just begun to reach the worst-affected areas, are appealing for assistance as it becomes more likely that damage to the water and sanitation systems could lead to widespread illness.
Many of the homes on Ha'apai, about 2,630 km (1,630 miles) northeast of the New Zealand capital, Wellington, rely on rooftop collection systems for drinking water. The destruction of those systems, aid workers say, is a cause for alarm.
"The main problem right now is water," Vanessa Lolohea, a member of the Tonga National Youth Council who is working with Oxfam, said in an email to Reuters.
"Mosquitoes and other insects are becoming a problem. The waterborne diseases like dengue, etc, may become a problem in the coming weeks."
There are five stages of tropical storm, with Typhoon Haiyan, which killed more than 4,000 people and caused widespread destruction in the Philippines in November rated at five, the most powerful.
(Reporting by Matt Siegel in CANBERRA and Thuy Ong in SYDNEY; Editing by Jane Wardell and Robert Birsel)