What is tularemia?

Causes and Symptoms

Tularemia is a bacterial
disease, caused by Francisella tularensis, that is of significant concern as a potential biological weapon because it is easily spread via airborne routes and is highly infectious—inhaling as few as ten bacterial cells is enough to cause disease in humans. If the bacteria were released in a densely populated area, then large numbers of people could fall ill within days.

The bacterium F. tularensis was discovered following a plaguelike disease that swept through ground squirrels in Tulare County, California, in 1911. Shortly after its initial discovery, it was demonstrated to cause disease in humans. The organism is common throughout North America and Eurasia. The disease is transmitted via a number of routes: bites of infected insects, contact with the carcasses of infected animals, eating contaminated food or drinking contaminated water, and breathing in the bacteria. The disease is not spread via person-to-person contact.

After infection, symptoms typically appear within two weeks. They include fever, chills, aches, pain, headaches, diarrhea, coughing, and, as the disease progresses, increasing weakness. Some individuals develop skin ulcerations and swollen lymph nodes, as well as pneumonia with accompanying chest pain, bloody sputum, and difficulty breathing—sometimes leading to respiratory failure.

Treatment and Therapy

Tularemia can be treated with a number of antibiotics, but preventing infections is ideal. Infection may be prevented by controlling exposure to insect and animal carriers of the bacterium, eating thoroughly cooked food, and drinking clean water.

Vaccines may also be used to prevent the disease. Russia has used a tularemia vaccine in areas where the disease naturally occurs since the 1930’s. A vaccine has been under review by the Food and Drug Administration (FDA) but is not yet available in the United States.

Perspective and Prospects

Since tularemia is easily contracted via inhalation of a small number of bacterial cells, it has been tested by some countries as a weapon to be released via the air. Japanese germ warfare units researched the use of tularemia as a weapon in Manchuria from 1932 through 1945. Tens of thousands of German and Russian troops were sickened by the disease on the Eastern Front in World War II, and some researchers suspect that the infections were intentional rather than natural. The United States and other countries have continued to research tularemia as a weapon since the war.

Bibliography

Farlow, Jason, et al. “Francisella tularensis in the United States.” Emerging Infectious Diseases 11, no. 12 (December, 2005): 1835-1841.

Henderson, Donald A., Thomas V. Inglesby, and Tara Jeanne O’Toole. Bioterrorism: Guidelines for Medical and Public Health Management. Chicago: American Medical Association, 2002.

Sidell, Frederick R., and Ernest T. Takafuji. Medical Aspects of Chemical and Biological Warfare. Washington, D.C.: Borden Institute, Walter Reed Army Medical Center, 1997.

Siderovski, Susan Hutton. Tularemia (Deadly Diseases and Epidemics). New York: Chelsea House Publishers, 2006. Print.