Scientists lifting the veil on a sting operation that netted drugs counterfeiters in China said on Tuesday it was vital for Asia's police and pharmaceutical watchdogs to work more closely in tackling these dangerous cheats.
In a paper published in the US online journal the Public Library of Science (PLoS), the scientists describe an unprecedented undercover mission that led to the arrest of a Chinese gang peddling fake anti-malaria pills.
Bogus treatments for malaria are rampant in Southeast Asia, placing lives at risk, they warn.
These pills are unlikely to contain enough artesunate -- the active ingredient that kills resistant malaria parasites in the blood -- and may even contain toxic substances that could sicken or kill the patient.
The investigation, dubbed Operation Jupiter, was coordinated with the help of Interpol and the World Health Organisation (WHO).
Lab experts with Britain's University of Oxford and Wellcome Trust analysed 391 samples of genuine and counterfeit artesunate, collected in Myanmar, Laos, Vietnam, Cambodia and on the Thai-Myanmar border.
They used a spectrometer to get a chemical ID of the pills and found that 195 out of 391 samples -- 49.9 percent -- had no or only small amounts of artesunate.
They also put the pills' packaging through a battery of tests, finding changes in hologram seals that, only to the expert eye and with the help of a microscope and ultraviolet light, pointed to fakery.
Many of the fake seals bore the logo "Guilin Pharma," the name of a large pharmaceutical company in Guilin, southern China.
But the ace in the hole was to use a high-technique called forensic polynology that not only found minute traces of pollen in the samples but identified their origin.
At least some of the counterfeit artesunate came from southern China, and this was supported by examination of the mineral calcite, found in some of the samples.
Armed with this information, the Jupiter chiefs handed the evidence to China's ministry of public security in March 2006.
A police swoop netted a suspect in Yunnan province who had bought a quarter of a million fake "Guilin Pharma" blister packs from a man with a counterfeit factory in Guangdong province. The suspects are awaiting trial.
The packs had been sold across the border in Myanmar and probably accounted for as many as the genuine Guilin Pharma treatments sold there.
The paper says the unique collaboration between forensic scientists, detectives, doctors and pharmacists should be the model for future offensives against the scourge of counterfeit drugs.
But, they say, "there are very few laboratories (only one in Asia/Pacific) with the appropropriate reference collection [of genuine drugs] and ability to analyse pollen assemblages in tablets, and the work is very labour-intensive and specialised and therefore expensive."
"If a collaborative forensive approach is to succeeed, DRAs (drug regulatory authorities) and their international collaborations will need to be strengthened and regional laboratories able to provide actionable evidence will be required."
The problem of counterfeit artesunate in Southeast Asia first surfaced in 1998. Among the many concerns raised by this traffic is the fear that, by taking an insufficient dose of artesunate, patients will help the malaria parasite to become resistant to the only widely-available, cost-effective drug.