The Secretariat of the Pacific Community, or SPC, says the number of dengue fever outbreaks in the region over the past year is unprecedented, and the reason for the increase in cases is unknown.
The team leader for surveillance at SPC, Adam Roth, says in the last 14 months, all four types of dengue fever have circulated the region at different times.
He says more research needs to be done on what caused the current outbreak, but says it could have been influenced by humidity, heat or urbanisation.
Dr Roth says dengue three has not spread in the region for more than 20 years, which makes people more susceptible to it.
"You have circulation of two dengue types - dengue one and dengue three. And also if you look for the past 14 months, you've had something like 14 dengue epidemics, and furthermore if you look at mosquito-borne viruses, you've had three chikungunya and two zika virus outbreaks."
Adam Roth says it is not known how many people have died in the region over this 14 month period, but hundreds of people have been sick, which has put a huge strain on public health systems.