Vanuatu's Ministry of Health says the number of confirmed dengue fever cases in the country has climbed to 313.
At the end of last month the number of cases of the disease was just 20.
Health officials have also confirmed the disease has spread to the island of Santo in the north, with 71 cases confirmed in the town of Luganville.
The Ministry of Health has ordered all households and schools there to trim their lawns and destroy any areas where mosquitoes are likely to breed.