NUKU‘ALOFA – Tonga has declared a zika epidemic after confirming five cases from testing nearly 260 people for the mosquito-borne virus, which has been linked to birth defects.

Dr Reynold Ofanoa, the chief medical officer at Tonga’s Department of Public Health, said none of the confirmed cases were pregnant women.

“The reason why we declared it a zika epidemic is we noticed an increase in patients coming in with acute fever and rash,” he said.

“According to the statistics that we received up until January 31, we have 259 cases with symptoms of zika virus.

“We took some blood tests and we had five confirmed cases,” Dr Ofanoa said.

There have been zika outbreaks in the Pacific region over the past few years, particularly in French Polynesia and Vanuatu.

In French Polynesia ,42 people developed Guillaume-Barre as a result of the infection. Guillain–Besyndrome (GBS) is a rapid-onset muscle weakness as a result of damage to the peripheral nervous system.

The territory’s health ministry said 18 malformed babies were born to zika patients, and about 10 to 12 of them had signs of microcephaly.

It said when zika struck the territory also had an outbreak of chikungunya and dengue.

American Samoa’s Department of Health has recorded 25 suspected cases of the Zika virus, but complications in the process of sending lab specimens to Honolulu to test for the virus has caused delays.

According to a health official the delay in sending specimens overseas is because the Honolulu laboratory which American Samoa uses has not been paid.

There are no confirmed cases of Zika in American Samoa.

An official from the US Centres for Disease Control and Prevention, Robert Chen, has arrived in territory to help the Department of Health.

Dr Chen said the response to protecting the public is already happening, and the health department is not waiting till the tests have confirmed the presence of this virus in the territory.

“I think the delay in specimens which will be resolved through the work of the Department of Health, and the CDC will be happy to support, and that’s not delaying the actions and response and those will continue to move forward quickly.”

The Health Department said it will again work with other departments as they did during the dengue and chikungunya outbreaks to get families to clean their own environments and get rid of mosquito breeding sites.

Samoa, which reported its first transmission last November, has been added to a list of more than 20 countries where transmission of the virus is ongoing.

Scientists suspect that when zika strikes a pregnant woman, it can cause her baby to be born with microcephaly, or an abnormally small head.

Dr Reynold Ofanoa said Tongan health authorities were monitoring pregnant women for signs of infection.

“We’re working with obstetricians to identify any cases of pregnant mothers who present with symptoms of zika to be tested and also to follow up their pregnancies until delivery.”

This week the World Health Organisation (WHO) declared the spread of the virus a global emergency.

A number of drug companies have since announced that they are working on a vaccine for the virus.

An Indian biotech firm claimed to have developed a vaccine for Zika, but says it will not be available for a few years without help from the government and the UN health agency.

The WHO advises prevention through using mosquito nets, protective clothing and insect repellent. - ABC