Tularemia

Tularemia (too-lab-REE-me-uh), sometimes called rabbit fever, is an infection caused by bacteria that can spread from wild animals to humans.

Do Rabbits Cause Rabbit Fever?

The bacterium Francisella tularensis (fran-sih-SEL-uh too-lah-REN-sis) causes tularemia. Most cases of tularemia in people in the United States result from contact with infected rabbits and deer, although the bacterium can also live in other small mammals and birds and in the soil.

Tularemia bacteria enter the body through the mucous membranes, the skin, the lungs, or the digestive system. Seven different forms of the disease exist:

* Ulceroglandular tularemia comes from handling an infected animal or from the bite of an infected tick, fly, or mosquito. An ulcer (an open sore) forms on the skin. Some symptoms include headache, fever, chills, and lack of energy.

* Glandular tularemia causes symptoms similar to those of the ulceroglandular form but an ulcer does not form. The bacteria may enter the body through small cuts in the skin. Most cases of rabbit fever in the United States are glandular or ulceroglandular tularemia.

* Oculoglandular tularemia comes from touching the eye with infected fingers. The eye becomes red and painful and has a discharge.

* Oropharyngeal tularemia arises from eating the undercooked meat of an infected animal or from drinking water contaminated by the bacterium. It causes digestive system symptoms, such as vomiting or diarrhea.

* Pneumonic tularemia results from inhaling spores (an inactive form of the germ enclosed in a protective shell) in dust from a contaminated area into the lungs. Other types of tularemia may also spread to the lungs.

* Typhoidal tularemia affects many organs of the body. This rare form of the disease occurs without any previous signs of infection in any specific part of the body.

* Septic tularemia is a severe form of the disease that affects the whole body. Someone with this form may go into shock and experience serious complications.

How Do People Contract Rabbit Fever?

People cannot catch tularemia from one another. Most cases in the United States occur when someone gets a bite from a tick, fly, or mosquito that has previously bitten an infected rabbit or deer. If a person is in contact with infected animals, the bacterium may be able to enter that person's body through small cuts on the skin. Hunters contract tularemia from handling carcasses or from cating undercooked, contaminated meat. In rare cases, people may breathe in bacterial spores that have been released into the air from the soil where the bacteria live. Drinking contaminated water is another rare but possible way to contract the discase.

Is Tularemia Common?

Tularemia occurs in the United States, Europe, and Asia, mainly in rural areas. Tularemia is highly infectious, but fewer than 200 cases in the United States are reported cach year (mostly from Missouri, Arkansas, and Oklahoma). Some additional cases may occur but remain unrecognized or unreported.

Tularemia affects people of every age, sex, and race. In spring and summer months, it occurs most often in children who become infected when playing outside. In fall and winter, hunters are more likely to contract the infection.