Work underway on single-dose smallpox vaccine

Researchers at St. Louis University are experimenting with a new, single-dose smallpox vaccine that could help stop infection during bioterrorist attacks.

The researchers are currently studying IMVAMUNE, a single injection of a high-dose vaccine. reports.

The difference between a single injection as opposed to traditional smallpox vaccines, which call for two low-dose injections, could be crucial if smallpox is ever released in the public, the researchers told

Dr. Sharon Frey, the principal investigator and professor of infectious diseases at Saint Louis University School of Medicine, said that speed will be essential during a bioterrorist attack.

“If there is a smallpox outbreak, getting people vaccinated as quickly as possible will be a matter of urgency,” Frey told “Giving a single injection of a much stronger vaccine could allow us to protect people much more quickly, when time is of the essence.”

The high-dose vaccine has not yet been tested in people, Frey said. Studies with animals showed, however, that the vaccine is well tolerated, according to the report.

Clinical trials will be performed on 90 volunteers at two centralized locations, Frey said.  Half of the volunteers will be given the high-dose version of IMVAMUNE and half will be given the standard dose.