Lesser doses of anthrax vaccine give the same protection as higher doses. People who got the former kind of injection experienced less pain but the protection against the disease remained the same. Since anthrax can be used as a biological weapon, the U S military is getting the vaccine made by Emergent BioSolutions, Maryland.

A study was conducted by Conrad Quinn of the U.S. Centers for Disease Control and Prevention on1,005 U.S. adults. It was observed that those who received three doses over six months showed the same immune response to those given the usual four doses over the same time.

"If you have a certain amount of vaccine and now you don't have to give all of that to complete one series, you have more vaccine," Quinn added.

Researchers said their research raises hopes that the vaccine which is routinely given to military personnel to defend them against biological warfare, will help in gaining a widespread acceptance and lessen the fear of side effects.

Anthrax can be a fatal infection caused by Bacillus anthracis bacteria. The fears in the minds of the people are based on a study of its spores which can be used as a biological weapon and are most deadly when inhaled.