PHNOM PENH – A little-known battle being fought in Cambodia could have global ramifications. The fight is against drug-resistant malaria.
The problem is more severe in Cambodia than anywhere else in the world, says Steven Bjorge, the World Health Organization's malaria team leader in Cambodia.
About 17 percent of all cases in the Cambodian-Thai border area of Pailin were drug-resistant in 2011, up from 10 percent the year before, according to Char Meng Chuor, director of the government’s National Malaria Center
. He says the drug-resistant disease has also spread to parts of Preah Vihear and Pursat, border provinces in Cambodia’s north and west.
Drug-resistant malaria first evolved in Cambodia in the 1950s and 1960s, according to Bjorge.
“Since then, every new drug seems to first become resistant in Cambodia or on the Thai-Cambodian border before anywhere else in the world,” he said.
Drug resistance occurs when a patient infected with the Plasmodium falciparum
parasite takes an incomplete or incorrect course of anti-malarial drugs. This allows the parasite to evolve resistance to that medicine, so patients must take another course of drugs under the supervision of a doctor, says Char Meng Chuor.
The problem is greatest in border towns with a lot of traffic. Here, migrant workers might buy the wrong drugs without seeing a doctor, or misuse treatment in other ways, says Uth Sophal, Pailin field officer for the health group the Malaria Consortium.
“Migrant people move from one province to another, so when they come to Pailin, which already has resistant malaria, when the mosquitoes bite those people, they will get that parasite and pass it from one province to another province, from one country to another,” he said.
With some help, health workers are hoping that will change.
The Malaria Consortium has created a network of volunteers at Pailin’s border crossing to check and evaluate migrant workers and treat them if they have malaria.
“When Cambodians cross the border, we measure their temperature,” Uth Sophal said. “If they have any kind of illness, we have to immediately treat them.”
University Research, a global health company fighting drug-resistant malaria in sub-Mekong Region countries, is trying to ensure migrant workers are given bed nets before they move through malaria-prone areas. It is also training local people to provide malaria.
Char Meng Chuor says Pailin is the key to stopping the spread of the drug-resistant disease. And the stakes are high.
“Don’t be confused, the resistance is not just one person’s issue,” he said. “Malaria drug resistance is a problem for the whole community ... If mosquitos are imported to other countries, it will go to other countries … This is a concern of the world about Cambodia now.”
Worldwide, malaria infects more than 200 million people each year and kills more than half a million, most of them in Africa, according to the World Health Organization
The WHO has been changing standard drug treatments to stay ahead of the parasite. Two months ago, it started using a drug called Malarone in Pailin, in the hopes of seeing a decrease.
In a normal case of malaria, a course of drug treatment can eliminate the parasite from the patient’s blood within three days. But in drug-resistant cases, this is not enough to clear the parasite. With these patients, it can take anywhere from five to 28 days to flush out the malaria parasite.
In Cambodia, the overall number of cases of malaria continues to drop, and with proper control, even the numbers of drug-resistant cases should fall, says Bjorge of the WHO.
“It is not a hopeless situation,” he said. “I am actually hopeful about the future because we are having a lot of success in Cambodia, despite the headlines saying that drug resistance is growing. The main message is that malaria is dropping in Cambodia, and the few cases that remain are the drug-resistant cases.”