Double jab needed for bird flu pandemic

Frontline healthcare staff should have a double flu jab to protect them against a future bird flu pandemic, suggest UK researchers.

Giving an initial injection against one strain of avian flu years in advance may 'prime' the immune system to fight a range of bird flu strains, said the team from the University of Leicester.

When a pandemic arrives, pre-vaccinated people could then be given a booster shot and be protected much more quickly.

The researchers compared the outcomes of people who received a booster jab - following an initial vaccine up to seven years ago - with people receiving the vaccine for the first time.

'We found that a single low dose booster vaccine, given seven years later, generated a very rapid response,' said lead researcher Iain Stephenson, consultant in infectious diseases at Leicester Royal Infirmary. 'Within one week of vaccination, over 80% of subjects had an excellent response to all strains of the H5 virus.

'In comparison, the unprimed subjects who were vaccinated for the first time needed two doses of vaccine and achieved protective levels of antibody after six weeks as expected,' he added.

The researchers said that hospitals and GP surgeries should stockpile pre-pandemic vaccines to proactively prime key personnel and first responders initially, followed by all members of the public.

New England Journal of Medicine (2008) 359: 1631-1633