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What is anthrax?

Anthrax is an infection caused by the bacterium Bacillus anthracis. The bacteria form spores that can live in the soil for many years. The spores are extremely tiny and are invisible to the naked eye. In large quantities, the spores are usually brown and powdery and may look like cinnamon or cocoa. However, the colour may be different if the spores are mixed with another substance. They do not have an odour and you cannot smell them. The infection is spread by the spores.

Anthrax usually occurs in farm animals such as cows and sheep. It is uncommon in humans.

Can anthrax spread from person to person?

No, anthrax cannot spread from one person to another.

Why is there concern about anthrax now?

Since the terrorist events of September 11, some people in the United States have received letters or packages that contain anthrax spores. To date, this has not happened in Canada. There have been false alarms and hoaxes in Canada but no one has received anthrax in the mail and no one has been infected with anthrax.

The chances of something like this happening in Canada are very low, but we know that you are concerned. We are providing you with these facts in order to keep you informed.

What are the signs of anthrax?

Anthrax spores can affect the skin (cutaneous infection), the stomach (gastrointestinal infection) or the lungs (inhalational infection).

In a skin infection, a small painless bump appears on the skin. This bump then becomes a blister and then an ulcer with a black centre. This is the most common type of infection.

In a stomach infection, the signs are fever, loss of appetite, vomiting and diarrhea.

In a lung infection, the first signs resemble the flu. Symptoms may include fever, sore throat and feeling unwell. After several days, this is followed by having trouble breathing. This is the most serious type of infection.

Can anthrax be treated?

Anthrax can be treated with several common antibiotics. It is important that antibiotics be started right away. Taking antibiotics "just in case" ahead of time is not recommended. This could lead to an increased risk of side effects, it could increase the drug resistance of the bacteria, and the increased use of antibiotics could also lead to a shortage of supplies.

How do I get anthrax?

Usually, the people who get anthrax are those who work with infected animals. Spores from infected animal hides may get into broken skin and cause skin infections. Eating meat contaminated with spores can cause stomach infections. Breathing in a large quantity of spores can cause a lung infection.

Signs of illness usually do not appear until 1 to 7 days after exposure to the anthrax spores.

If you receive a letter or package that contains anthrax spores, you may get a skin or lung infection if you touch or breathe in the spores.

Read the following fact sheet on what to do about suspicious letters or packages in your mail.