Just why the attacks failed is not known, but some experts suspect the cult did not sufficiently refine the particle size of its agents and that it was working with an avirulent strain of anthrax.

Just why the attacks failed is unclear, but some experts suspect the cult did not sufficiently refine the particle size of its agents and that it was working with an avirulent strain of anthrax.

but not in commensal (i.e., avirulent) strains? What genes are highly expressed during infection of the human (or animal) host? What genes are required for growth in the host? The answers to these ...

For example, highly virulent (harmful) pathogens will almost always lead to disease when they hit the body and have a short incubation period. Less virulent pathogens or avirulent (not harmful) ones ...