Travellers heading to the Pacific are being urged to protect themselves from mosquito bites, as dengue fever cases in the region reach their highest level in almost a decade.

Several Pacific Island nations — including Samoa, American Samoa, Cook Islands, French Polynesia, Kiribati, Nauru, Tonga and Tuvalu — are experiencing a sharp increase in infections.

New Zealand health authorities have also reported a significant rise in returning travellers who have picked up the sometimes deadly disease while overseas.

National Clinical Director for the National Public Health Service Dr Susan Jack said Samoa had been particularly affected, with over 2000 cases recorded since an outbreak was declared on 17 April.

“Sadly, some people have also died from the disease,” Dr Jack said.

New Zealand does not have mosquitoes capable of spreading dengue, and the virus cannot be passed from person to person. However, people can be infected by mosquitoes in regions where dengue is present. There is currently no dengue vaccine available in New Zealand.

Dr Jack said Auckland had seen a noticeable surge in dengue cases among returning travellers.

“There were 34 confirmed cases of dengue reported in Auckland in July among people coming back into New Zealand – with approximately half acquired in Samoa – compared with just five cases at the same time in 2024,” Dr Jack said.

“Between 1 January and 31 July this year, there have been 103 cases recorded in Auckland – almost double the total for all of 2024, which saw 54 cases. About a third of this year’s cases have required hospitalisation.”

Nationally, 208 cases of dengue have been confirmed so far this year.

“This is why it's important that people living in New Zealand who are travelling to these areas where dengue is widespread take precautions to avoid being bitten by mosquitoes and follow local public health advice,” Dr Jack said.

Children aged 10 and under, and adults over 60, are particularly vulnerable to severe forms of the illness.

Travellers are advised to sleep in screened areas or under mosquito nets, keep windows and doors closed, wear light-coloured clothing that covers arms and legs, and apply insect repellent containing less than 35 per cent DEET.

Dr Jack said most people infected with dengue do not show symptoms, but those who do may experience a sudden high fever, severe headache, pain behind the eyes, muscle and joint pain, nausea, vomiting, tiredness and a fine, itchy rash.

Anyone experiencing symptoms while travelling should seek medical advice promptly.