The web is studded with so-called online pharmacies that promise to ship Tamiflu - as well as Viagra, painkillers and a whole range of other powerful drugs - to anywhere in the world, with few and sometimes no questions asked.
Some of these companies are legal and fulfill a useful social role by pushing down prices, especially in the United States where tens of millions of poor people have little or no health insurance.
Yet many operate illegally, using the border-free realm of the internet to make a fast and potentially dangerous buck.
They promise to sell these drugs without first requiring a doctor's prescription or even a cursory assessment of any symptoms; all that's needed is a mailing address and a credit-card number.
The goods are readily dispatched across frontiers, in itself an illegal act in some jurisdictions.
Risk of scams
Health experts and many in the pharmaceutical industry itself are aghast at seeing vital drugs peddled like sweets.
They say people are being exposed to the risk of scams, of bogus medication and of possible side-effects from complex drugs that often should only be taken under a doctor's supervision.
"It is a concern, a real concern, and we are taking it very seriously," said David Reddy, a senior executive at Tamiflu's maker, Roche, who is in charge of the company's strategy for a flu pandemic.
European governments say
there will not be drug shortages
"Tamiflu is a prescription drug. People should go to their physicians, get their prescriptions and get it from a bona-fide pharmacy, because no one can vouch that what they obtain from the internet is in fact the real drug."
Reddy, in a phone interview with AFP, said Roche had heard of
reports of internet sales "of a drug that was purported to be Tamiflu but in fact was not". He declined to give details until the matter had been investigated.
"It is a risk that exists for all drugs, not just Tamiflu," World Health Organisation (WHO) spokesman Maria Cheng told AFP.
"It's a very clear loophole ... it's obviously something that needs to be regulated."
The American Medical Association (AMA) and its British counterpart are campaigning vigorously about online drug sales.
"Consumers who turn to illegal internet pharmacies to fill prescriptions run the risk of exposure to drugs that may be counterfeit, altered or contaminated," says the AMA.
The British Medical Association (BMA) has taken an even tougher line, warning the public not to buy drugs anywhere online.
People have been warned not to
buy drugs online
"One of the reasons is of course that the patient does not have the benefit of a full medical consultation and nor does the supplier have certainty that the information supplied by the buyer is correct," the BMA said.
Governments around the world are building up stockpiles of Tamiflu in fear that the H5N1 avian influenza virus, currently restricted to poultry and wild birds and to humans in close proximity, may eventually mutate into a global killer.
No one knows how many prescription drugs are sold online or how many companies or individuals have been punished for illegal sales.
Web pharmacies rarely show an address or even a telephone number.
"There's no way of monitoring purchases over the internet," a spokesman for Britain's Department of Health said. "There's no way you could come up with even a guess."
The anecdotal evidence is that the business is booming in the US - a figure of 1% of the total market for prescription drugs is aired by people in the industry.
Interest in Europe appears to be far smaller, explicable because of universal health coverage and the far lower cost of medications there.
"There's no way of monitoring purchases over the internet"
Department of Health,
Despite this, and repeated pledges by European governments that no one will go short of Tamiflu if the pandemic erupts, there seems to be a clear eagerness for buying Tamiflu online in Europe.
Several online pharmacies pitching to clients in France said on Tuesday that they could not cope with transactions because of their payment system was overloaded.
Governments are aware of the problem of online abuse but turn a blind eye to it, especially if it involves a cross-border case where prosecution is costly and may be impossible, said a source in the French pharmaceutical industry.