Cambodia’s Dengue Fever Crisis

Cambodia has run out of its main weapon for fighting dengue fever, a chemical that kills mosquito larvae, as the aid-dependent country battles an unprecedented outbreak of the sometimes fatal disease that mainly affects children.

The medical staff at the national dengue control center are optimistic that the worst is over, however, and are hoping that the drop in new cases that began in the third week of July will continue.

Still, another 13,000 or so dengue cases are predicted during the next five months, bringing the total for the year to “not less than 40,000”, according to a forecast made over the weekend. Last year there were about 12,300 dengue cases in Cambodia.

“We’ve run out of Abate,” Dr. To Setha said on Monday, referring to the granular form of the chemical that is used to kill the larvae of the dengue mosquito in its main breeding site in Cambodia – water-storage containers.

His center, which has a staff of nine and an annual budget of $150,000, depends on various donor agencies, including the World Bank and the Asian Development Bank, for money to buy Abate, insecticide, spraying machines, and to conduct emergency public education.

The result is that Cambodia has to limit its dengue prevention efforts to “preemptive strikes” on areas of high population density. Its “Abate distribution area” is limited to 15 of its 23 provinces and even within these provinces it is further limited to districts with more than 200 people per square kilometer.

This year outbreaks began in districts adjacent to the abate distribution area, To Setha said.

Even though the rainy season arrived two months earlier than usual, a round of Abate distribution – which costs about US$1 million – had been completed in the targeted area, he said.

Staff at his center had known in mid January, and informed global health bodies, that a surge in dengue cases was likely in the coming rainy season due to a higher than usual number of cases in the preceding months, as well as a change in the prevailing serotype of the virus, which has four.

Dengue is a fast-moving disease that causes a sudden onset of fever and severe bone and muscle aches, followed by a bright red blood rash that often appears on the legs before spreading to the chest.

“We can’t do what we want to do [for prevention],” To Setha said. Cambodia lacks the resources to expand its prevention efforts and additional funding from donors does not arrive until after outbreaks begin, regional and local officials say.

Donor agencies are swift to send out press releases trumpeting their assistance, but those dependent on them say the funds are often slow in arriving and officials are sometimes left scrambling to borrow from other projects or paying out of pocket while they wait for the money to arrive.

To Setha identified the long time it took to import Abate is another hindrance. An order placed with a private company last year did not arrive until the end of June. All of that has been used, along with more than 30 tons Thailand rushed over, and it could be two months before Cambodia receives more Abate, he said.

The Abate is crucial because it can be safely added to containers storing drinking water. Most Cambodians lack piped water and collect rainwater in concrete storage containers. Researchers say the containers comprise 80 percent of the dengue mosquitoes’ breeding sites in Cambodia but their efforts to develop inexpensive and durable mosquito-proof lids have failed.

They have been testing alternatives to Abate for several years and believe they have found one that is cheap, effective, community-based and environmentally safe. A pilot project that began in a 14-village commune west of Phnom Penh in 2004 has used guppy fish to eliminate larvae from water-storage containers.

Some of the villages have been dengue-free this year and there have been only a few cases in the entire commune, say residents of Roilang Gruel village, where the project began, as well as researchers. The commune, Trapeng Kong, is in Kampon Speu province, which so far this year has had the fourth highest number of dengue cases per capita in Cambodia.

Researchers are excited by the project but say they lack the staff and funding to train the local volunteers needed to expand the project throughout rural Cambodia. They estimate the annual cost of maintaining the project at 20 US cents per household.

Meanwhile, hospitals continue to be overwhelmed with dengue patients, with shocked parents and grandparents filling in for nurses.

For example, at Kompang Cham Hospital, about 200 kilometers north of the capital, the death toll from dengue reached 47 last Wednesday, compared to 9 last year and 4 in 2005, said the chief of the Pediatric Department Dr Chroeng Norith. In the small provincial hospital, patients crowd in and there is no room left. The admissions ward has been shifted outdoors.

With timely and proper treatment dengue patients can be saved, but they are arriving at the hospital too late, says Dr. Chroeng, or after they have received the wrong treatment at privately-run clinics. The hospital has treated 1,109 dengue patients so far this year, most since May, he adds. The pediatric ward has just 25 beds. Nursing students have been recruited to pitch in and Medicins Sans Frontiers sent an emergency medical team.

Most of the children who died from dengue at this hospital did so in its bird flu ward – where the severe cases of dengue are treated. It was empty when the crisis began and, because it was built with overseas funding, well-equipped.