Scientists said a “universal” flu vaccine that protects against numerous strains of the virus for decades could be available in as little as three years.
Early trials of the two-step immunisation are already under way, with tests on human patients possible in 2013.
A US team working with mice, ferrets and monkeys primed subjects’ immune systems by introducing influenza DNA. A “booster” consisting of a regular seasonal flu vaccine was then administered.
The combination proved to be effective against flu viruses of different subtypes and from different years, the researchers reported in the journal Science.
Although the “priming” vaccine came from a 1999 virus, antibodies were generated that neutralised other strains. Mice and ferrets produced antibodies not only against viruses dating from before 1999, including one that emerged in 1934, but also strains from 2006 and 2007.
Study leader Dr Gary Nabel, from the US National Institute of Allergy and Infectious Diseases in Bethesda, Maryland, said: “We are excited by these results. The prime-boost approach opens a new door to vaccinations for influenza that would be similar to vaccination against such diseases as hepatitis, where we vaccinate early in life and then boost immunity through occasional, additional inoculations in adulthood.”
Copyright Press Association 2010