Our award-winning reporting has moved

Context provides news and analysis on three of the world’s most critical issues:

climate change, the impact of technology on society, and inclusive economies.

Malaria treatment fails in Cambodia because of drug resistance - researchers

by Alex Whiting | @AlexWhi | Thomson Reuters Foundation
Thursday, 7 January 2016 23:30 GMT

In a 2010 file photo, a patient is comforted in the only hospital in Pailin in western Cambodia. Research shows artemisinin-based therapies - currently the most effective treatment against malaria - are taking longer to cure some of the patients in this town bordering Thailand. REUTERS/Damir Sagolj

Image Caption and Rights Information

Researchers find treatment fails because of resistance to piperaquine, as well as artemisinin

LONDON, Jan 7 (Thomson Reuters Foundation) - Malaria-carrying parasites in parts of Cambodia have developed resistance to a major drug used to treat the disease in Southeast Asia, according to research published on Thursday in The Lancet Infectious Diseases journal.

The drug piperaquine, used in combination with the drug artemisinin, has been the main form of malaria treatment in Cambodia since 2008.

The combination is also one of the few treatments still effective against multi drug-resistant malaria which has emerged in Southeast Asia in recent years, and which experts fear may spread to other parts of the world.

"(Treatment) failures are caused by both artemisinin and piperaquine resistance, and commonly occur in places where dihydroartemisinin-piperaquine has been used in the private sector," researchers said.

Artemisinin resistance has been found in five countries in Southeast Asia - Cambodia, Laos, Myanmar, Thailand and Vietnam.

Resistance to both artemisinin and drugs used in combination with it has developed in parts of Cambodia and Thailand.

Experts are particularly concerned that artemisinin resistance will spread to sub-Saharan Africa where about 90 percent of malaria cases and deaths occur.

"Because few other artemisinin combination therapies are available, and because artemisinin resistance will probably accelerate resistance to any partner drug, investigations of alternative treatment approaches are urgently needed," the researchers said.

They suggest an alternative treatment should be tested, comprising artesunate, a form of artemisinin, combined with mefloquine, a different long-acting partner drug.

"The intensive spread of artemisinin resistance in Cambodia is rapidly threatening to reduce the efficacy of all artemisinin combination therapies used in this country and in bordering areas of Vietnam, Laos, and Thailand," the article said.

Malaria patients in areas with drug-resistant malaria should be treated in hospital, the researchers said.

"... intensified efforts are needed to discourage what appears to be a highly ineffective approach of self-treatment in the private sector."

The research was produced by the U.S. National Institute of Allergy and Infectious Diseases.

About 3.2 billion people - almost half the world's population - are at risk of malaria, according to the World Health Organization.

(Reporting by Alex Whiting, editing by Tim Pearce. Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women's rights, trafficking, corruption and climate change. Visit www.trust.org)

Our Standards: The Thomson Reuters Trust Principles.