Transmission and Spread of Anthrax

How is anthrax transmitted?

Infection occurs when the spores enter the body through a cut, abrasion, or open sore, referred to as cutaneous anthrax, or by ingestion or inhalation of the spores. Once inside the body, anthrax spores germinate into bacteria that then multiply and secrete three proteins: protective antigen (PA), lethal factor (LF), and edema factor (EF). Individually these proteins are non-toxic, but they can become lethal if allowed to combine and interact on and within the cells of the exposed human or animal.

Is anthrax disease contagious?

No. Inhalational anthrax disease is not considered a communicable disease that is spread from person-to-person like the flu or common cold. Even if you have symptoms of anthrax disease, you are not contagious to anyone with whom you come in contact.

Can anthrax spores be spread?

While the disease itself is not a communicable disease, it is possible for anthrax spores to be re-aerosolized or spread long distances through the air. An analysis of the anthrax attack on the Hart Senate Office Building revealed that people outside the building were exposed to the anthrax spores released inside the building ^5,6. This finding supports both the idea that the anthrax spores used could travel long distances through the air and the idea of cross-contamination, whereby individuals outside the building may have been exposed through contact with re-aerosolized spores from individuals who had been inside the building.

How can I help protect myself against anthrax?

The best way to protect against infectious diseases is to get vaccinated before exposure. A vaccine is currently available for pre-exposure protection against anthrax. It is called BioThrax^® (Anthrax Vaccine Adsorbed).

BioThrax may not protect all individuals vaccinated, particularly patients with impaired immune responses due to congenital or acquired immunodeficiency, or immunosuppressive therapy. Individuals are not considered protected until they have completed the full vaccination series.

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