Thirty-four percent of malaria-endemic countries are complying with WHO guidelines to monitor artemisinin resistance within their borders, the agency said in a report on Thursday, CBS News reports (11/18). Reuters reports that artemisinin “is the best drug available against malaria, especially when used in artemisinin combination therapy (ACT), which combines it with other drugs that finish off the [malaria] parasite” (Nebehay, 11/18).

“WHO guidelines state that countries should study patients for signs of resistance to first and second line malaria drugs at least once every two years,” Emerging Health Threats writes. But between 2008 and 2009, “just 31 of the 92 countries endemic for malaria worldwide carried out monitoring studies to check the efficacy of the drugs they use to treat the disease,” the WHO report found, according to the news service. “Without regular monitoring and reporting of antimalarial drug resistance, the disease burden and the economic costs of malaria will rise dramatically,” the report states (11/18).

The WHO’s malaria drug efficacy report “urges countries to be more vigilant in drug monitoring to allow for earlier detection of resistance to anti-malarial treatments,” the U.N. News Centre writes. Pascal Ringwald of WHO’s Global Malaria Program’s Drug Resistance and Containment Unit said, “A greater political commitment to support and sustain national monitoring of the efficacy of anti-malarial medicines is critical to prevent a wider emergence of artemisinin resistance.”

The report did find that overall ACTs endorsed by national malaria programs “remain effective against malaria, with cure rates generally above 90 percent,” the news service reports. “In countries with cure rates lower than 90 percent, policy change is ongoing to implement efficacious replacement malaria treatments,” according to the news service (11/18).

The WHO also warned that artemisinin resistance “appeared to be spreading in the region from the Cambodia-Thailand border, where it was first detected,” Agence France-Presse reports. “There is some early evidence that resistance to artemisinins may also be emerging on the Myanmar-Thailand border,” said the WHO in a press release. “There is also concern that resistance could spread from the Cambodia-Thailand border to Africa, as it did with anti-malaria drugs such as chloroquine and sulfadoxine-pyrimethamine in the 1960s and 1970s,” it continued (11/18). Ringwald said that authorities in Myanmar will meet in December or January to discuss a proposed strategy to contain the spread of drug-resistant malaria. Vietnam has also requested help to contain suspect cases in one of its provinces, he added, Reuters reports (11/18).