Health officials in the U.S. have expressed concern that with the current panic in many countries regarding bird flu, a counterfeit industry to produce the drug Tamiflu may already be in existence.
It is believed at present that Tamiflu is one of the few drugs that can treat the feared avian influenza.
U.S. Food and Drug Administration Director Dr. Andrew von Eschenbach has therefore set up a "rapid response team" to make sure enough of the legitimate drug will be manufactured in the case of a pandemic of H5N1 avian flu.
Officials are apparently confident that there will be enough of the antiviral medication to treat Americans in the annual epidemic of seasonal flu, which kills an average of 36,000 people in the United States alone every year.
However Health and Human Services Secretary Michael Leavitt says there is some concern that there may be a threat of counterfeiting with respect to Tamiflu.
The H5N1 strain of avian influenza which is affecting flocks of poultry in many parts of Asia and some parts of eastern Europe, has killed more than 60 people so far in four countries and millions of birds have been destroyed.
As yet it does not easily infect humans, but experts fear it will acquire this ability and cause a pandemic.
The virus while it appears resistant to one of four available influenza drugs, amantadine, two other drugs, Roche's Tamiflu, and GlaxoSmithKline's Relenza, work against the virus, and there is evidence that another older influenza drug called rimantadine may also work.
Media headlines about Tamiflu have of course encouraged the panic, and countries are now scrambling to stockpile the drug which is great news for drug company Roche who cannot make the drug fast enough to meet all the demand.
The company says it will talk to other companies about licensing it to meet demand.
Meanwhile the FDA is worried about supplies, and concerned that counterfeiters using the Internet may see an opportunity.
Apparently the FDA is not aware at present of any counterfeit Tamiflu cases in the United States, but they say steps are in place to deter counterfeiters and parties who sell fraudulent products to treat or prevent Avian flu.
The agency has also promised to fast-track any potential new influenza drugs, and say that in the event of a pandemic, such new medications could be made available under Emergency Use Authorization.
The Centers for Disease Control and Prevention Director Dr. Julie Gerberding, says people should not worry about a shortage of influenza drugs, and while there have been more prescriptions for Tamiflu this year than last year, the manufacturer still has several million doses in the pipeline.
According to Von Eschenbach people should not try to get Tamiflu prescriptions from their doctors in order to stockpile for themselves.
He has concerns is that if people stockpile or accumulate the drug and begin to self-medicate, that will not only undermine the effect of the drug, but will also increase the possibility of adverse effects.