A novel method of protection against bird flu has been studied and the findings are being reported by scientists at the University of Rochester. This involves a way of getting around the problem that if an epidemic of bird flu hits, it would take months to develop a vaccine. Also, two doses of vaccine would be required to prevent infection.
The idea behind this study is a" prime and boost" method of vaccination. An initial dose of the vaccine is given to introduce the body's defences to the new type of flu. Then if there is an epidemic, a second shot specified for that strain of flu can be given, which would result in quicker results in protection. People most likely to be infected can thus be prepared.
The study was done on 37 people who were inoculated with one dose of the vaccine in 1998.They were given a booster dose with a vaccine for a different strain of the virus in 2005.Rochester volunteers were given their first doses of the vaccine made from the strain which appeared in Hong Kong. The people given the booster doses responded better than those inoculated for the first time.
More than 50% of the booster dose recipients had better defences against bird flu than those given their first dose and even those given two doses. Dr. Anthony Fauci at the National Institutes Of Health says that these findings add scientific credibility to the idea of "prime and boost" though policy decisions require further work.
The principle is similar to that used for protection against flu. Though different strains of the virus appear every year, a single initial dose of vaccine followed by an annual booster keeps the immune system effective.