A look at malaria drugs being used in places that are hotbeds for the mosquito-borne illness finds that many of them are substandard or even fake.

And that's a big problem. Combinations of well-made drugs, including those that contain arteminisin, are a cornerstone of malaria treatment. But when some of the drugs are of poor quality or are outright fakes, people don't get well. Ineffective combinations can promote drug-resistant malaria.

From 20 to 42 percent of the malaria medicines examined in Southeast Asia and sub-Saharan Africa were crummy or counterfeit, according to a review of various studies conducted there. The analysis was just published online by the journal The Lancet Infectious Disease.

In countries where malaria is prevalent, 25 percent of all drugs consumed are malaria medicines, the researchers noted. "Poor-quality antimalarial drugs are an immediate and urgent threat...." they wrote.

They recommend that governments take action to "better define and eliminate both criminal production and poor manufacturing of antimalarial drugs."

Last month, researchers published findings that malaria parasites resistant to the last, best drug treatment, called artemisinin combination therapy, or ACT, are infecting people along the border of Thailand and Myanmar.

That's distant from a previously discovered bunch of cases in Cambodia. And it's a different type of resistant malaria, which means it arose independently of the Cambodian type rather than spreading from there.

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