Wednesday, March 29, 2006
Bird flu vaccine only works at highest dose - study
An experimental vaccine against H5N1 bird flu only appears to work at the very highest doses, meaning it will be harder than feared to protect the population against a pandemic, researchers said on Wednesday.
The vaccine, made by a unit of Sanofi-Aventis
“It is a bit of muted good news in that we are going in the right direction, but the sobering news is we have a long way to go,” National Institute of Allergy and Infectious Diseases Director Dr. Anthony Fauci said in a telephone briefing before the findings appeared in the New England Journal of Medicine.
These findings mean there is only enough H5N1 vaccine now in the U.S. stockpile to protect about 4 million Americans in a pandemic, Fauci said. These would likely be key health-care workers and people working to make the vaccine.
Everyone else would have to wait while a pandemic spreads, relying on public-health measures such social distancing—meaning closing businesses, schools and using masks, gloves and other protective equipment—in the meantime.
The H5N1 avian influenza virus has spread in birds at an alarming rate in recent months, sweeping out of east Asia across to Europe and down into Africa. Officials believe it will become entrenched in wild birds across the globe within a year or two.
It remains difficult for humans to catch but has infected 186 people in eight countries and killed 105, according to the latest World Health Organization figures. Experts fear the virus could evolve into a form passed easily from human to human, causing a pandemic that could kill tens of millions.