These mill workers were mainly at risk for cutaneous (“skin”) anthrax.

In this vaccine study, 25 out of 754 unvaccinated workers got infected with anthrax, but only 1 out of 379 vaccinated workers did (92.5% protection).


The 92.5 % protection level was combined, for both cutaneous and
inhalational anthrax infection.

There was an unexpected outbreak of inhalational anthrax during this study.

In the mill-workers study, 5 unvaccinated workers developed inhalational anthrax, but no vaccinated worker did.

Four of the 5 unvaccinated workers died of inhalational anthrax (80% fatal).

The anthrax vaccine originally tested is basically the same as the one used today.

The current vaccine is more potent and more pure than the 1950’s original vaccine.


The vaccine used by Brachman used the same basic ingredients as today’s vaccine.