Smallpox vaccine study goes nationwide

ST. LOUIS -- With concerns heightened about the potential use of the smallpox virus in a terrorist attack, researchers this month will begin a national study to see if diluted vaccine can boost the immunity of those inoculated decades ago.

The clinical trial, sponsored by the National Institutes of Health, will involve 927 volunteers and will be conducted at Saint Louis University Medical Center and six other sites. It is a follow-up to a 90-person pilot study conducted at Saint Louis earlier this year.

Concern about a potential biological attack involving smallpox, an often deadly virus declared eradicated two decades ago, has prompted the White House to consider making the vaccine available to health care workers and the public.