Scientists Testing New Poultry Vaccine Against "Bird Flu"

Microbiologist Mike Perdue of USDA's Agricultural Research Service traveled last week to Hong Kong to deliver for further tests a new poultry vaccine with potential to protect poultry against the "bird flu" (avian influenza H5N1).

The vaccine was jointly tested by scientists with the ARS Southeast Poultry Research Laboratory at Athens, Ga., and researchers at Protein Sciences Corporation, Meriden, Conn. In December 1997, the vaccine was shown to protect chickens from the virus in controlled studies at the ARS facility at Athens.

Under the research partnership between ARS and Protein Sciences, the scientists developed a previous vaccine to protect against a different avian influenza strain, one that appeared in Mexico in 1995. The Mexican strain is in the same genetic family--H5--as the Hong Kong virus, but gave no evidence of infecting people.

Scientists from the Hong Kong Department of Agriculture and Fisheries and zoo officials from Hong Kong's urban services department will test the vaccine's potential to protect poultry and other bird species from the bird flu strain. An effective vaccine could reduce the likelihood of the virus' spread in poultry if it returns. The virus is 100 percent lethal in chickens.

Perdue and other scientists at SEPRL have evaluated the genetic make-up of North American and Asian-origin H5 viruses. Protein Sciences Corporation researchers combined the researchers' insights and genetic material from the viruses with patented technology to develop their vaccines. The technology uses an insect virus, baculovirus, to produce huge quantities of a single viral protein. In ARS tests conducted in Athens, the vaccines have provided 100 percent protection to chicks exposed to H5. Unvaccinated exposed birds died.

The Protein Sciences vaccines for avian influenza are in the process of being evaluated for approval in the United States in case of another outbreak. One advantage of vaccination with these new vaccines is that the baculovirus-produced proteins will allow regulatory agencies to readily distinguish vaccinated birds from birds that have been infected naturally with the influenza virus.

Scientific contacts: Mike Perdue, ARS Southeast Poultry Research Laboratory, Athens, Ga. Phone (706) 546-3433, fax (706) 546-3161, mperdue@asrr.arsusda.gov; Bethanie Wilkinson, Protein Sciences Corporation, Meriden, Conn. Phone: (203) 686-0800, fax (203) 686-0268, bew@proteinsciences.com.