American Samoa's Department of Health is carrying out further testing to determine if there's a new type of dengue fever present in the territory following confirmation that two people died from dengue last month.
The Department's epidemiologist Scott Anesi says they are gathering more information about the two deaths to help with their investigation.
Mr Anesi says they are looking at their age groups, villages, correlation of where they worked, shop or went to school to seeing if there are similarities with the dengue virus occurring in the island countries where there have been recent outbreaks.
He says the deaths are unusual because of the sudden deterioration from flu like symptoms.
"So our case definition that we are coming up together is not really matching the sudden onset and deterioration of some of the cases that we are seeing so we are very surprised at how fast that the cases deteriorated and also leading to death and we are definitely interested in the serotying because what we are trying to see is if there's maybe possible co-infections as we are still in the outbreak of the flu or if its a serotype that we haven't seen in the territory before."
Our correspondent says the villages of the two people who died from dengue last month, a 37 year old man and a ten month old baby had not been disclosed.
Meanwhile, three people suspected to have dengue fever were admitted to the LBJ Hospital on Thursday.
LBJ's Infection Prevention nurse Sharmaine Mageo says the three were admitted so they can be closely monitored.
She also says a 16 year-old girl who had symptoms of the disease passed away last week, and the hospital is sending samples off-island for confirmation of the girl's cause of death.
Our correspondent says results will not be known for at least a week.
And in neighbouring Samoa, a public alert for dengue fever was issued yesterday afternoon by the Minister of Health after confirmation two people died from the disease American Samoa.
Samoa's Health Ministry has called clinicians and health personnel to be updated on the symptoms of and management practices for dengue fever, dengue haemorrhagic and dengue shock syndrome - and mentions the tests to be carried out.
Amongst the measures listed in the alert notice for non-health personnel are the spraying of flights between the two Samoas and other Pacific Island countries, the wearing of long sleeve shirts and pants to avoid mosquito bites - and for breeding sites of the insect to be destroyed.
The Health Ministry says the last dengue outbreak in Samoa occurred in 2008 with the circulating serotype 4.