The increasing prevalence of a strain of malaria resistant to the conventional anti-malarial drug artemisinin, is worrying health experts both here and regionally and prompting a fresh approach.

The World Health Organization tomorrow is set to launch an “emergency response” to combat anti-malarial drug resistance, the organisation said yesterday.

Artemisinin – a traditional Chinese herbal drug – is the most effective way to combat the disease currently. Used in combination with a partner anti-malarial drug such as teraquine, it kills the majority of malarial parasites at the start of treatment while its partner clears up the remainder.

But resistance to the drug is growing in the Greater Mekong Subregion – which includes Cambodia, Myanmar, Thailand, Vietnam, Laos, and China’s Yunan and Guangxi provinces.

If the drug-resistant parasite is not contained and spreads elsewhere, “the consequences for global health could be incalculable,” said Dr Shin Young-soo, WHO regional director for the Western Pacific.

While parameters of the “emergency response” won’t be made public until tomorrow, WHO malaria scientist and team leader Dr Steven Bjorge said it would focus around bolstering monitoring efforts and taking steps to control the resistance.

“This emergency response is to prolong the life of artemisinin as a treatment or if possible, to eliminate artemisinin resistance as a problem altogether,” added Bjorge.

“If we lose [artemisinin-based treatments], we will have trouble replacing it.”

In Cambodia, artemisinin resistance is most apparent in Pailin and Battambang, said Dr Char Meng Chour, head of the National Centre for Parasitology, Entomology and Malaria Control (CNM).

In some areas, drug resistance has reached “critical levels”, said Meng Chour, forcing authorities to completely switch to a different anti-malarial drug – malarone.

“We are hoping that by removing the drug from the market, the drug-resistant form of the parasite might die out and we can use artemisinin again.”

In Battambang, the situation is being monitored closely. But provincial health department director Kuy Sok said malarone is only a stop-gap measure, as it is much more expensive than conventional artemisinin treatments.

That said, Cambodia has seen dramatic results in its battle against malaria. In the first three months of this year, only three died from the disease – compared with 22 in the same period last year, according to data from the CNM.

The advance means the Kingdom is on track to eliminating the disease altogether by 2025, said Meng Chour.

Funding for this fight has been secured through to 2015, he said, even though major donor Global Fund announced as of this month it would no longer channel funds though the CNM due to findings of “serious financial wrongdoing” last year. 

ADDITIONAL REPORTING BY MOM KUNTHEAR