What Is Anthrax?

Anthrax is an infectious disease caused by the bacterium Bacillus anthracis. It can occur in humans when they have been exposed to contaminated animals or tissue from these animals.

Anthrax is mostly found in South and Central America, Southern and Eastern Europe, Asia, Africa, the Caribbean, and the Middle East. It has even been found in wild livestock in the United States, although it is rare. It is mostly found in agricultural areas of these regions.

The bacteria can be transmitted to humans through inhalation, skin contact, or ingestion. The bacteria can infect a human who breathes in spores from a contaminated animal, touches one of these animals (alive or dead), or eats undercooked meat from them.

Symptoms of anthrax include:

• A skin infection that initially looks like an insect bite may occur. It then turns into an ulcer with black, necrotic skin in the center.
• If the bacteria are inhaled, initial symptoms may seem like a common cold.
• Anthrax that has been ingested causes severe abdominal cramping, vomiting, vomiting blood, nausea, diarrhea, and fever.

Anthrax is treated with antibiotics. If diagnosed and treated early, the disease may be cured. Without treatment or delays in starting medicine, anthrax can be fatal.

What Is the Anthrax Vaccine?

The anthrax vaccine does not contain dead, weakened, or living bacteria. It is called a cell-free filtrate vaccine. This means that the bacteria used to make the vaccine cannot cause disease.

The vaccine also contains elements that allow for easy storage: aluminum, aluminum hydroxide in a solution of sodium chloride, benzethonium chloride, and formaldehyde.

It should be stored in a cool place, 36ºF-46ºF, but it should not be frozen.

In December 2008, the FDA approved the use of an anthrax vaccine adsorbed (BioThrax, manufactured by Emergent BioSolutions). The vaccine is given into the muscle. The schedule for this vaccine is 0 and 4 weeks and 6, 12, and 18 months.

Who Should Get Vaccinated and When?

The following people (aged 18 to 65 years) should get vaccinated. Those who:

• Are lab workers who may come into contact with B. anthracis
• Come into contact with animal meat, hide, or fur that may have been exposed to anthrax spores
• Work with animals and animal products in areas where anthrax infection commonly occurs (not common in the US)
• Are in the military run the risk of exposure to anthrax as a biological warfare weapon

What Are the Risks Associated With the Anthrax Vaccine?

• Common, mild side effects include soreness or redness at the injection site.
• A more severe reaction may be significant swelling in the arm where the shot was given.
• Rare, but serious risks include systemic reaction—This condition is usually associated with anaphylaxis, which can cause extreme allergic response, including interrupted breathing, hives, dizziness, and arrhythmic heart rate.
• Other serious adverse events may also occur.

Who Should Not Get Vaccinated?

Those who should not get vaccinated include:

• The general public who are not at significant risk of exposure to anthrax
• Very young children, the elderly, or people with compromised immune systems
• Pregnant women should not be routinely vaccinated

What Other Ways Can Anthrax Be Prevented Besides Vaccination?

• Take precautions when dealing with animals or animal products that could possibly be contaminated with B. anthracis.
• Begin a course of antibiotic treatment if you have been exposed to anthrax.

What Happens in the Event of an Outbreak?

It is not believed that anthrax can be spread from person to person. If an outbreak occurred and a large number of people were exposed to the bacteria, the US would administer antibiotics to everyone exposed.