An expected July and August outbreak of dengue fever cases was less severe than officials had feared, according to Dr Chang Moh Seng, dengue officer for the World Health Organization.
Health officials have been warning since April that Phnom Penh, Battambang and other urban areas could face a dengue epidemic during this year’s rainy season. In past epidemics in Cambodia—in 1995 and 1998—the number of dengue fever cases took a sharp leap upward in August.
Clear, stagnant water provides ideal breeding conditions for the tiger mosquito, which carries the dengue virus. But the distribution of millions of tablets of the larvicide Abate in April and July, as well as an education campaign and an insecticide-spraying program, apparently minimized the number of dengue cases, Chang Moh Seng said.
“This year it peaked in June and July because of some rural outbreaks. The Abate distribution has also played an effective role in the urban areas,” he said.
Because human immunity to the virus normally lasts only three years, officials feared an epidemic this year would be just as deadly as the 1998 outbreak, when the country suffered its worst dengue outbreak ever.
That year, there were 16,215 dengue cases and 475 child deaths nationwide. In 1995, which until then had been Cambodia’s worst epidemic, more than 10,000 people contracted the disease and 447 died.
This year, the number of cases in Phnom Penh have been low—just 34 cases in August and 140 in July, Chang Moh Seng said. So far, there have been 521 cases in the capital, he said.
Nationwide, there were 6,249 cases and 144 deaths from the beginning of the year through the end of August, according to Dr Ngan Chantha, dengue program manager at the National Malaria Center.
Dengue usually affects small children and foreigners who have not built up resistance to the disease. Dengue is most common where population is dense.
