However, since most probably in a biological warfare situation, communications and support services will degenerate to a point of complete chaos, in vitro data would not be available. Recent tests with anthrax raise fears that U.S. vaccine can be defeated. The concern stems from recent evidence that Russia may have mixed together several strains of anthrax, presumably to enhance the lethality of its germ weapon. There is evidence also that Russian scientists have produced strains of anthrax genetically engineered to produce new toxins. The vaccine works by disabling a component of anthrax known as protective antigen, which helps the microbe's two toxins penetrate the cells they are attacking.
Anthrax is one of the most effective and lethal bioweapons in existence.
Smallpox Smallpox is caused by a virus. The virus spread when an uninfected person comes in direct contact with a sick person and breath in the virus. After two weeks, the incubation period of the smallpox virus, the infected person develops high fever, muscle aches and pains. After about three days of fever the person breaks out in a rash all over the body. At first it looks like red spots, and the spots gradually become blisters about the size of a pencil eraser.