Study reaffirms data on resistant malaria

Photo by: SOVAN PHILONG
A woman in Chamkarmon district treats a mosquito net with repellant.

The Phnom Penh Post
Friday, 31 July 2009
JAMES O'TOOLE

Research in New England Journal of Medicine offers more evidence of drug-resistance trend.

ANEW study has confirmed that malaria parasites in western Cambodia are becoming increasingly resistant to drug treatment, underscoring the urgency of treatment and containment efforts already under way in the Kingdom.

In an article published Thursday in the New England Journal of Medicine, a group of doctors detailed a study in which they compared the effectiveness of artemisinin, the drug most commonly used in malaria treatment, in the cases of infected patients from western Cambodia and from northwestern Thailand.

In 40 patients from Pailin province, the median time that the drug took to clear the parasite was 84 hours, with 55 percent of patients still infected after three days of treatment. In 40 patients from Wang Pha, in Thailand's Nan province, by contrast, the median clearance time was the expected 48 hours, with only 8 percent of patients still infected after three days.

Ros Seyha of the World Health Organisation (WHO) said the presence of artemisinin-resistant malaria in Cambodia had already been discussed in the scientific community, but he stressed the importance of continuing research on this issue.

"Monitoring drug sensitivity is not something that should be done in just one study. There must be ongoing observations of what's going on as treatment is being delivered to the target group," he said.

Duong Socheat, director of the National Malaria Centre (NMC) , said the results in the Journal were "not really surprising".

Since February, he has been supervising a US$22 million effort to contain artemisinin-resistant malaria in western Cambodia, in partnership with the WHO and with a grant from the Bill and Melinda Gates Foundation.

Duong Socheat told the Post in May that a fully artemisinin-resistant strain of malaria would be "a disaster". He said malaria centre and its partner organisations hoped to rid Cambodia of the disease by 2015, but that costs remained an obstacle.

Drug resistance in the Kingdom has been exacerbated by the fact that some patients can only afford a partial course of treatment, killing all but the most resilient parasites.

Though the WHO and the NMC have worked to educate pharmacists about the importance of full treatment, costs remain prohibitive for many Cambodians, Duong Socheat said.