Thursday, June 15, 2006
New vaccine protects ferrets from H5N1 bird flu virus: study
A US research team reported on Wednesday that they had successfully protected ferrets against the deadly H5N1 bird flu virus.
These findings were published in the June 15 edition of the Journal of Infectious Diseases.
The researchers, headed by Robert Webster, created the bird flu vaccine by recombining the HA and NA genes of an avian influenza virus strain acquired in Hong Kong, China, (A/HK/213/03) and weakening its virulence.
They then tested the bird flu vaccine’s effect using young adult ferrets. One group of ferrets that received a dose of the vaccine was tested with a wild-type H5N1 virus strain four weeks after vaccination. Another group that received two doses was tested with a bird flu virus strain one week after the last dose.
All vaccinated ferrets were protected against a most pathogenic “Vietnam” strain (A/Vietnam/1203/04), the researchers found.
“No clinical signs of infection were observed, virus replication was significantly reduced and was restricted to the upper respiratory tract, and spread of the virus to the brain was prevented,” they said.
Furthermore, the two-dose vaccination induced higher levels of antibodies that were cross-reactive to distinctly different H5N1 virus strains, they added.
Sources for this avian influenza story: