Tularemia is a rare infectious disease. Also known as rabbit fever or deer fly fever, it typically attacks the skin, eyes, lymph nodes and lungs. Tularemia is caused by the bacterium Francisella tularensis.
The disease mainly affects rabbits, hares, and rodents, such as muskrats and squirrels. Tularemia can also infect birds, sheep and domestic animals, such as dogs, cats and hamsters.
Tularemia spreads to humans in several ways, including insect bites and direct exposure to an infected animal. Tularemia is highly contagious and potentially fatal, but can usually be treated effectively with specific antibiotics if diagnosed early.
Most people exposed to tularemia who become sick generally do so within three to five days, although it can take as long as 21 days. There are several types of tularemia, and which type you get depends on how and where the bacteria enter the body. Each type of tularemia has its own set of symptoms.
This is the most common form of the disease. Signs and symptoms include:
People with glandular tularemia have the same signs and symptoms of ulceroglandular tularemia, but without skin ulcers.
This form affects the eyes and may cause:
This form affects the mouth, throat and digestive tract. Signs and symptoms include:
This type of tularemia causes signs and symptoms typical of pneumonia:
Other forms of tularemia also can spread to the lungs.
This rare and serious form of the disease usually causes:
If you think you may have been exposed to tularemia, see a doctor as soon as possible. This is especially true if you have been bitten by a tick or have handled a wild animal in an area where tularemia is found and have developed a fever, skin ulcers or swollen glands.
Tularemia doesn't occur naturally in humans and isn't known to pass from person to person. However, tularemia occurs worldwide, especially in rural areas, because many mammals, birds and insects are infected with F. tularensis. The organism can live for weeks in soil, water and dead animals.
Unlike some infectious diseases that spread from animals to people in just one way, tularemia has several modes of transmission. How you get the disease usually determines the type and severity of symptoms. In general, you can get tularemia through:
Although anyone of any age can develop tularemia, engaging in certain occupations or activities or living in certain areas pose a greater risk.
Tularemia has been reported in the United States, Canada, Mexico, Japan and Europe. In the United States, it's usually more common in Arkansas, Missouri, Oklahoma and South Dakota, though there were outbreaks in Colorado, Nebraska and Wyoming in 2015. Tularemia has also been reported in parts of Massachusetts, including Martha's Vineyard and Nantucket.
The following can increase your risk of developing tularemia:
Left untreated, tularemia can be fatal. Other possible complications include:
There's currently no vaccine available for tularemia. If you work in a high-risk occupation or live in an area where tularemia is present, these measures may help reduce your chance of infection:
Protect yourself from insects. Tularemia in the United States is often related to a tick bite. In other parts of the world, tularemia is more commonly contracted through mosquito bites.
If you spend time in tick- or mosquito-infested areas, wear long-sleeved shirts and long pants, tuck your pants into your socks, and use a broad-brimmed hat to help protect your face and neck. Use an insect repellent with 20% to 30% DEET, picaridin or IR3535, but follow the manufacturer's directions carefully. Apply insect repellent in moderation, and wash it off at the end of the day.
Check yourself for ticks often and remove them immediately if you find any. Be sure to check your pets too.
Because it's rare and because it shares symptoms with other diseases, tularemia may be difficult to diagnose. If you've participated in any activities that increase your risk, such as hunting rabbit, let your doctor know.
Tularemia can usually be diagnosed through blood tests. One test looks for antibodies to the bacteria, and that test won't show that you've had the infection until several weeks later. You may also have a chest X-ray to look for signs of pneumonia.
Tularemia can be effectively treated with antibiotics given by injection directly into a muscle or vein. The antibiotic gentamicin is typically the treatment of choice for tularemia. Streptomycin is also effective, but can be hard to get and may have more side effects than other antibiotics.
Depending on the type of tularemia being treated, doctors may prescribe oral antibiotics such as doxycycline (Oracea, Vibramycin, others) or ciprofloxacin (Cipro) instead.
You'll also receive therapy for any complications such as meningitis or pneumonia. In general, you should be immune to tularemia after recovering from the disease, but some people may experience a recurrence or reinfection.
You're likely to start by seeing your primary care doctor. However, in some cases when you call to set up an appointment, you may be referred immediately to an infectious diseases specialist.
Here's information to help you prepare for your appointment.
Preparing a list of questions for your doctor will help you make the most of your time together. For tularemia, some basic questions to ask your doctor include:
Don't hesitate to ask any other questions you may have.
Your doctor is likely to ask you a number of questions, including: