Experimental virus material contained live bird flu virus, flu vaccine maker confirms

Baxter International, a major manufacturer of flu vaccines, admitted this past week that it released a contaminated product containing a combination of H3N2 seasonal flu viruses and unlabelled H5N1 viruses from a plant in Austria. Portions of that product were supplied to the Austrian research firm, Avir Green Hills Biotechnology. Avir then sent portions of it to its subcontractors in the Czech Republic, Slovenia and Germany.  When the firm in the Czech Republic inoculated ferrets with the product, they died, alerting scientists to the possibility that the product contained live H5N1 avian flu virus. Baxter's Director of Global Bioscience Communications Christopher Bona confirmed in an email that it was live. The incident is being described as a "serious error" on the part of Baxter, which is trying to secure a European license for an H5N1 vaccine.

The fact that human H3N2 and avian H5N1 viruses co-mingled causes great concern to public health experts, which describe the co-mingling as a "dangerous practice that should not be allowed to happen." In fact, the release of the virus combination could have had dire consequences. Although H5N1 doesn't easily infect humans, H3N2 viruses do. Should a person be vaccinated with a mixture of the H5N1 and H3N2 viruses, that individual could "serve as an incubator for a hybrid virus able to transmit easily to and among people," say experts. And that process, called re-assortment, can result in the creation of a pandemic virus.

Fortunately, it appears that none of the 36 or 37 people exposed to the contaminated product became infected. Says Medical Officer Roberta Andraghetti from Copenhagen, Denmark, "At this juncture we are confident in saying that public health and occupational risk is minimal at present. We have no evidence of any reassortment having occurred. And we have no evidence of any increased transmissibility of the viruses that were involved in the experiment with the ferrets in the Czech Republic." To date, Baxter has not publicly released information on how the incident occurred. Christopher Bona said that concerns about revealing proprietary information about Baxter's production process precludes the company from making additional information available to the general public.

The incident is under investigation by the four European countries involved. Those investigating governments are working in close collaboration with the WHO and the European Centre for Disease Control in Stockholm, Sweden. Says Andraghetti, "We are in very close contact with Austrian authorities to understand what the circumstances of the incident in their laboratory were. And the reason for us wishing to know what has happened is to prevent similar events in the future and to share lessons that can be learned from this event with others."

News Release: Baxter admits contaminated seasonal flue product contained live bird flu virus  www.google.com  February 28, 2009