Fresh outbreaks of dengue fever - a serious viral disease spread by the bite of infected mosquitoes - at two Pacific destinations favoured by New Zealand tourists are causing concern.
Three cases of the fever have been confirmed on Rarotonga in the Cook Islands and public health officials there expect more cases.
And the New Caledonian Government has issued an alert for an impending epidemic there.
It says six new cases have been confirmed two days after an initial outbreak when five people were reported infected.
People with dengue fever typically suffer flu-like symptoms such as irregular high fever, muscle or joint pains, severe headaches and rashes on various parts of the body. But a potentially lethal form known as "severe dengue" (previously known as dengue haemorrhagic fever) affects most Asian and Latin American countries, according to international health authorities.
New Zealand travellers are regularly warned on the Government's SafeTravel website seasonal outbreaks in North Queensland and in many parts of the Pacific, and are told there is no vaccine to protect against dengue.