Australian facility plays key role in bird flu research

CSIRO's Australian Animal Health Laboratory (AAHL) is hosting a project aimed at reducing the impact of the H5N1 avian influenza virus.

AAHL's high security disease biocontainment facility in Geelong is hosting Cornell University's Professor Ton Schat, an expert in avian virology and immunology, for six months as he investigates the disease-causing potential of a mutated form of H5N1.

Schat recently arrived at the Geelong facility, starting the project which will involve two three-month stints of research.

The genetic makeup of the H5N1 viruses obtained from lethal human influenza cases showed that in approximately 50% of cases there was a specific change in one amino acid in the pB2 gene. This change was also associated with high rates of mortality in Chinese birds, including barheaded geese, cormorants and gulls. Typically these birds are carriers of H5N1 and do not suffer any ill-effects.

Schat says the research aims to determine the disease-causing potential of the changed virus using reverse genetics to generate two isogenic viruses which differ only in the one amino acid.

"The mutation has been found in a majority of the lethal human cases, but we don't know if the mutation occurred in the patient or in the bird before it was passed on to the patient," Schat says.

"This project hopes to determine if this change in the virus influences its ability to cause disease in chickens and ducks. We will investigate if the mutated virus changes again when reintroduced to birds and if birds can carry the changed form."

He believes that learning more about the changed form of H5N1 could help develop a better vaccine for chickens. A new vaccine for poultry would also have benefits for humans.

"If we can protect the chicken population, this will also protect people as exposure to the virus will be removed or reduced," Schat says.

Schat will perform all of the animal research with H5N1 wearing a breathing air hood, working inside special sealed laboratories at AAHL. The virus samples will be supplied by the Centres for Disease Control (CDC) in Atlanta, Georgia.