Health Information

Q Fever

What is Q Fever?

Q fever is caused by a specific type of bacteria carried by animals, most commonly sheep, goats and cattle. When you inhale barnyard dust particles contaminated by infected animals, you may become infected.

Most people with Q fever have no initial symptoms, but some experience flu-like symptoms or develop pneumonia or hepatitis. This acute form of Q fever can lead to chronic Q fever, which is a serious disease that can last three to four years, can affect your heart, liver, brain and lungs, and is often fatal.

Acute Q fever usually clears up within a few weeks with no treatment. If you have symptoms, your doctor will likely prescribe antibiotics. Chronic Q fever requires specific antibiotic treatment, multiple follow-up tests and possibly surgery.

What causes Q Fever?

Coxiella burnetii bacteria typically infect animals. The infection most commonly affects sheep, goats and cattle, but can also affect pets, such as cats, dogs, birds and rabbits. These mammals transmit the bacteria through their urine, feces, milk and birth products, such as placenta and amniotic fluid. When these substances dry, the bacteria in them become part of the barnyard dust that floats in the air. The infection is transmitted to humans through the lungs, when you inhale contaminated barnyard dust.

Rarely, you can get Q fever from drinking large amounts of unpasteurized milk or by being bitten by an infected wood tick.

Treatment of Q Fever

Treatment for Q fever depends on whether the infection is acute or chronic and whether you're pregnant.

a) Acute Q fever treatment
Mild or non symptomatic cases of acute Q fever often get better in about two weeks with no treatment. However, even if you have no symptoms your doctor may want to provide treatment in order to prevent future complications.

The standard treatment for acute Q fever is doxycycline, an antibiotic. The severity of your infection will determine the length of time you need to take the antibiotic, but the usual medication course is two to three weeks. It's important to get treatment as soon as you notice symptoms, because the antibiotics are the most effective when they're initiated within one week of symptoms' onset.

Sometimes, acute Q fever can come back. Your doctor may ask you to return in six months for serologic testing. If Q fever bacteria antibodies are found again, you'll likely need another round of antibiotics.

b) Chronic Q fever treatment
Chronic Q fever is treated with a combination of antibiotics taken for at least 18 months. In more-advanced cases, you may need to take the antibiotics for as long as four years.

If you have Q fever endocarditis, you may need surgery to remove or graft damaged heart valves or repair an aneurysm. Although treatments are available, complications can quickly multiply, and they may prove fatal. Even after successful chronic Q fever treatment, you'll need to go back for follow-up tests for years in case the infection returns.

c) Treatment of Q fever during pregnancy
Treating Q fever during pregnancy can be a challenge, because the usual antibiotics prescribed for Q fever are not recommended during pregnancy. Some women elect to wait until after delivery to treat Q fever, but that decision has risks as well. Pregnancy is a risk factor for developing chronic Q fever, and acute Q fever can cause multiple complications for the baby as well. If you're pregnant and have Q fever, be sure you understand all of your treatment options and their risks.