The World Health Organisation is rushing drugs and equipment to Papua New Guinea amid fears that tens of thousands of people may be at risk from malaria.
WHO officials say there have been many deaths from the disease recently, despite locals saying conditions have improved in some areas since early May, when the mass distribution, of anti-malarial drugs, began with Australian aid assistance.
They say clinics, in some remote Highlands villages, have been overrun with cases.
A WHO malariologist, Dapeng Luo, says the outbreak there, seems to have reached epidemic proportions.
He says in the Waghi River Valley, in Chimbu Province, around thirty thousand people, in 60 village,s are believed to be threatened by the disease.