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Plague is an infectious disease of animals and humans caused by a bacterium called Yersinia pestis. People usually get plague from being bitten by a rodent flea that is carrying the plague bacterium, by handling an infected animal or by inhaling respiratory droplets containing the bacteria. 

Outbreaks in people still occur in rural communities or in cities.

Wild rodents in certain areas around the world are infected with plague. Rock squirrels and their fleas are the most frequent sources of human infection in the southwestern U.S. 

Domestic cats (and sometimes dogs) are readily infected by fleas or from eating infected wild rodents. Cats may serve as a source of infection to persons exposed to them. 

Pets may also bring plague-infected fleas into the home. In the United States, most human cases of plague occur in northern New Mexico, northern Arizona, southern Colorado and California.

There are three forms of plague:
A person usually becomes ill with bubonic plague two to six days after being infected. This form is characterized by fever, chills and enlarged, painful lymph nodes. This form can progress to pneumonic or septicemic plague.

Pneumonic plague usually results when the bacteria in the body moves to the lungs and causes severe respiratory disease. Inhalation of respiratory droplets from cats and humans with pneumonic plague is another way of contracting the pneumonic form. Symptoms are fever, chills, cough and difficulty breathing. Rapid shock and death can occur if not treated early.

Septicemic plague occurs as a result of the bacteria entering the bloodstream and results in the following symptoms: fever, chills, prostration, abdominal pain and shock.

Modern antibiotics are effective against plague, but if an infected person is not treated promptly, the disease is likely to cause illness or death. There is no licensed vaccine against plague.

Plague is listed as one of the Centers for Disease Control and Prevention's bioterrorism agents.

For more information on plague, see the CDC's Web site at http://www.cdc.gov/ncidod/dvbid/plague/index.htm .

If you have any questions or concerns, call the Public Health Flight at 846-3461.