Patients with dengue fever resting under mosquito nets in a gym in Maasin, a town in the Philippine province of Iloilo, yesterday. On Monday, the Philippine Department of Health issued a national alert to warn of an outbreak of dengue fever, with more than 106,630 cases recorded in the first half of this year and 456 deaths - most of them children under five. The outbreak is in five of the six provinces of Western Visayas region: Aklan, Antique, Capiz, Guimaras and Iloilo. Health Secretary Francisco Duque III said the number of dengue cases was an 85 per cent increase from the 57,564 cases reported over the same period last year. Western Visayas had the most number of reported cases so far, with 13,164, followed by Calabarzon (11,474 cases), Central Visayas (9,199 cases), Soccsksargen (9,107 cases) and Northern Mindanao (8,739 cases), reported the Philippine Daily Inquirer.

Dengue is the world's fastest-growing infectious disease, causing an average of over half a million potentially fatal infections annually and around 20,000 deaths, most of them children. In Singapore, the number of dengue cases in a week has hit a 31/2-year high, with 666 cases recorded from July 7 to 13, the National Environment Agency said. As of Sunday, there were 7,374 dengue cases this year, about five times more than the 1,481 cases seen over the same period last year. In Sri Lanka, the dengue death toll has risen to 58, while over 29,000 people have been infected with the virus so far this year. In Laos, Health Minister Bounkong Syhavong said the capital Vientiane is experiencing an outbreak of the Type 2 dengue virus, the most toxic strain of the virus.