What is tularemia?
Tularemia is an infectious disease caused by the bacterium Francisella tularensis, and is considered to be one of the most infectious disease-causing bacteria known. These bacteria are most commonly found in rabbits, hares, voles, muskrats and other wild rodents, but can also be found in sheep, cattle, and cats. About 200 cases of tularemia in humans are reported each year in the United States, mostly in people who live in the south-central and western states. However, tularemia occurs sporadically through the United States, including West Virginia. Tularemia is also know as “rabbit fever” and “deerfly fever”. In addition to causing natural disease, F. tularensis has been implicated as a possible agent for use in bioterrorism. Use of tularemia as a biological weapon would most likely occur as an aerosol release of the bacterium, although the potential for alternate delivery also exists.
What are the symptoms of tularemia?
A skin ulcer and swollen, painful lymph glands are common symptoms of tularemia when the bacteria are introduced into the skin. If the tularemia bacteria are eaten or consumed in drinking water, they can cause sore throat, abdominal pain, vomiting, diarrhea, and mouth ulcers. If the tularemia bacteria are inhaled, symptoms would include fever, chills, headache, muscle aches, joint pain, dry cough, weakness, and pneumonia. Swollen and painful eyes can result from bacteria being introduced into the eyes.
How soon after exposure would symptoms begin?
Symptoms generally develop between 3 and 5 days after exposure, but possible as long as 14 days following exposure.
How is tularemia treated?
Tularemia can be treated with antibiotics from a physician. If you think you have tularemia, consult your doctor immediately.
How is tularemia spread?
People can get tularemia by being bitten by ticks, deerflies and some other insects that have fed on an animal that has the disease. The disease is also spread to humans by handling dead infected animals, by eating or drinking contaminated food or water, or by inhaling the bacteria. People have not been known to transmit the infection to other people.
Who is most at risk for tularemia?
People of all ages can get tularemia. People are more at risk if:
- They hunt or trap rabbits or other rodents.
- They are exposed to ticks and biting insects.
- They eat undercooked rabbit meat or meat from other wild rodents.
- They skin, process, or cook rabbit meat or meat from other wild rodents.
How can I protect myself?
- Protect against tick and deerfly bites by wearing protective clothing and by using insect repellents.
- Tell children not to handle dead or sick animals.
- Wear rubber glovers when handling dead rabbits or other possibly infected animals.
- Cook game meats thoroughly. Freezing does NOT kill the bacteria — frozen killed rabbit meats can remain infective for more than three years.
How could an intentional release of tularemia be managed?
Early recognition by physicians is key to managing this disease. Infected patients can be treated with antibiotics, and exposed individuals may take antibiotics to prevent disease.
Tularemia Information for Public Health Officials
Unique Epidemiological Characteristics
- Natural reservoir in West Virginia – squirrels, voles, rats, mice, rabbits, hares
- A newly-reported case should by investigated urgently considering:
- contact with animals,
- aerosol exposure from contaminated hay/grass,
- Incubation: 1-14 days
- No person-to-person transmission
- Mortality: 30-60% without treatment (pneumonic or systemic disease) – emergency
- Environmentally hardy in moist, cold environments
- Prophylaxis: effective only if initiated within 24 hours of exposure (ciprofloxacin or doxycycline)
- Treatment: effective if begun early with Streptomycin, gentamicin > ciprofloxacin, doxycycline
- Initial screening by hospital laboratories; confirmation by OLS
Employee Health Considerations:
- Exposed employees should be started on antibiotics id they can be identified within 24 hours of exposure; if identified after 24 hours, they should be placed under surveillance and begun on treatment if symptoms develop
- Employees doing environmental investigation should have personal protective equipment and training if exposure is likely / possible
- Standard precautions
Lifesaving interventions – in order:
- Recognition / reporting / case-finding + early appropriate therapy
- Collect and analyze risk information to identify source ANDidentify the exposed population to be placed under surveillance
- Physicians: recognition / reporting / treatment
- ICPs: reporting, active surveillance procedures
- Labs: screening tests and procedure for referral of specimens to OLS.
- Local health departments, regional epidemiologists: Investigation / NPS issues
- IDEP / DSDC / BPH: investigation / communication / prioritization of control measure