Linda Hoang, the program head of the bacteriology and mycology laboratory at the B.C. Centre for Disease Control, recalls how a patient threw doctors for a loop back in 2006. He first visited a clinic in the Interior for what appeared to be an infected insect bite, which eventually healed. Six weeks later, he was back with a painful lump in his groin. Tests eventually revealed he had tularemia. The rare illness is caused by a bacterium that’s as lethal as anthrax and has the same potential for use in biological warfare.

“When this 58-year-old patient presented, the last thing we thought of was tularemia,” Hoang tells the Georgia Straight in a phone interview. “It’s below the radar”¦.It’s an unusual organism. The incidence is very low—we have one or two cases a year—but it can cause significant disease.

“It hasn’t been used the way anthrax has, but the potential is there,” adds Hoang, a doctor and medical microbiologist with a special interest in agents of bioterrorism. “It was one of the things we had to be prepared for during the Olympics.”

The 2006 diagnosis prompted a case report and review by the B.C. Centre for Disease Control’s public health microbiology and reference laboratory. Researchers looked at 16 other cases in the province between 1991 and 2007 and published their findings in the current issue of the B.C. Medical Journal.

Tularemia, caused by the Francisella tularensis bacterium, can be hard to detect because it can lead to many different symptoms: fever, lesions, enlarged lymph nodes, sore throat, nausea, vomiting, and bloody diarrhea among them. It has to be identified via lab tests and treated with appropriate antibiotics.

According to the BCMJ review, tularemia—which gets its name from Tulare County, California, and is today often called rabbit or muskrat fever—exists throughout the United States and Canada. First identified in 1912, it was described as causing a “plague-like illness” in ground squirrels.

Tularemia is not known to be spread from person to person. People are most commonly infected through insect bites or by handling or coming into contact with infected animals. Ticks are associated with about 90 percent of tularemia cases in the States, and F. tularensis has been found in ticks in B.C., Ontario, and Saskat ­chewan.

Eating or drinking contaminated food or water is another source of infection, and people can also get sick by inhaling the bacteria. It can exist, for example, on hay or soil that’s been contaminated by animal urine or feces.

Decaying animal carcasses are another source of airborne particles. An outbreak in Martha’s Vineyard, Massachusetts, in 2000 was traced to the inhalation of bacteria from the body of a dead rabbit after a man had been exposed while cutting brush. Lawn-mowing was found to be another risk factor in a subsequent study into that outbreak, which affected 15 people, one of whom died as a result.

More than 100 species of wild or domestic animals can carry the bacterium, including skunks, raccoons, rodents, sheep, beavers, muskrats, deer, and cats, and deer flies are also a vector.

The BCMJ report found that half of the cases reviewed were linked with animal or insect bites, and most were acquired in rural areas. All but two occurred between May and October. The ages of the patients ranged from 10 to 90. There was at least one death that likely resulted from tularemia-related acute respiratory distress syndrome. Many of the patients were treated with several ineffective courses of antibiotics.

People who hunt or trap animals, skin carcasses, or handle wild animals need to familiarize themselves with tularemia risk factors and symptoms, Hoang says. But she’s also encouraging health professionals and the public alike to be aware of the illness.

“In the summertime, people spending time in the woods and the wilderness of B.C. should be cautious,” Hoang says. “Take precautions to reduce the risk of insect bites by reducing exposure: wear long-sleeve shirts and pants and wear repellent.

“If you’ve had an insect bite and any unusual symptoms, let your doctor know so that they can think of possible diagnoses and send you for appropriate tests,” she adds.

“After contact with animals, wash your hands. If you come across a dead animal, don’t carry it away yourself. Contact your local public-health authority.”

When left untreated, tularemia causes death in 30 percent to 60 percent of cases.

The bacterium is extremely infectious. According to the U.S. Centers for Disease Control and Prevention, it could be used as an airborne weapon for mass exposure by inhalation.

“People who inhale an infectious aerosol would generally experience severe respiratory illness, including life-threatening pneumonia and systemic infection, if they are not treated,” the CDC’s Web site states. “The bacteria that cause tularemia occur widely in nature and could be isolated and grown in quantity in a laboratory, although manufacturing an effective aerosol weapon would require considerable sophistication.”

The biological agents of highest concern to the CDC include anthrax, smallpox, botulism, Ebola hemorrhagic fever, and tularemia.

After the September 11, 2001, terrorist attacks, the CDC recommended heightened surveillance for any unusual disease outbreaks.