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 , 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, a review of various studies conducted there. The 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 findings that malaria parasites resistant to the last, best drug treatment, called , 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.

"Anti-malarial control efforts are vitally dependent on artemisinin combination treatments," and of Columbia University wrote in a Lanceteditorial last month. "Should these regimens fail, no other drugs are ready for deployment, and drug development efforts are not expected to yield new antimalarials until the end of this decade."

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