Could drug pirates wreck the world's best hope of combatting malaria? A new drug, artesunate, developed from traditional Chinese medicine, is being hailed as the best chance of tackling malaria - which kills millions of people every year in Africa and SE Asia.

But it's being undermined by widespread counterfeiting, particularly by counterfeit drugs containing a small amount of artesunate which then allow the disease to develop a resistance to the drug. And ironically it's Chinese drug pirates who are believed to be largely responsible.

A WHO health official says there'll be a public health catastrophe if resistance to artesunate is allowed to develop. Interpol tell us ethnic Chinese criminal gangs, operating across borders, are largely to blame for the counterfeits.

Jill McGivering travels to SE Asia, where conterfeit drugs are widely sold - and where resistance first developed to quinine and chloroquin, the drugs previously used against malaria. Could history be about to repeat itself with artesunate?

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