An epidemiologist fears Pacific people could be facing a potentially life threatening dengue outbreak not seen in more than a decade.
There are four types of dengue fever, with symptoms including fever, headache, aches, nausea and eye and joint muscle pain.
The World Health Organisation's Dr Eric Nilles says the region could be on the verge of an outbreak of type 2 dengue, that has been confirmed in the Federated States of Micronesia.
He says elsewhere type 1 and type 4 dengue have been found.
Dr Nilles says a person infected with one type of dengue will subsequently only be immune to that type, but not necessarily to other types while at a higher risk of developing more severe symptoms.
"We at the Fiji WHO office are continuing to work closely with the various other countries and territories in the Pacific to monitor the dengue situation and provide technical and material support when possible to those countries."
Dr Eric Nilles says dengue samples have been sent to Australia for analysis and people with symptoms should seek medical attention immediately.