Q Fever

What is Q fever?

Q fever is an illness you get from dust or animal products containing the bacterium Coxiella burnetii (C. burnetii). Sheep, goats, cattle and other animals can carry C. burnetii. It can get into the soil around them, allowing it to spread to people.

Why is it called Q fever?

The “Q” in Q fever stands for query. It got the name “query fever” when people first started coming down with it (in the 1930s in Australia and the 1940s in the U.S.) because doctors didn’t know what caused it. So they had questions (or “queries”) about the cause of the fever.

What is chronic Q fever?

Chronic Q fever is a serious form of Q fever that can affect your heart, your blood vessels, your bones and other parts of your body. It affects 1 to 5% of people who’ve had a C. burnetii infection. It can start months or years after your initial symptoms go away and can lead to life-threatening complications. Sometimes people with chronic Q fever had no symptoms with their initial infection. The most common form causes inflammation in your heart (endocarditis).

What happens when you get Q fever?

Q fever can cause a wide variety of symptoms, but the most common ones are flu-like. The bacterium that causes it, C. burnetii, can infect your lungs, heart, brain, bones or other parts of your body and cause symptoms there. Some people have extreme tiredness (fatigue) and other symptoms for months or years. Chronic Q fever can be life-threatening.

Who does it affect?

Q fever most commonly affects people who live or work near farms or who come in contact with farm animals. This includes veterinarians, anyone who helps with animal birthing, and farm, ranch or slaughterhouse workers.

Who is at higher risk for severe Q fever?

Some people are at higher risk of serious effects of Q fever. Pregnant people are at higher risk for pregnancy complications and miscarriage. You’re at higher risk for chronic Q fever, a more serious illness than acute Q fever, if you:

• Have a history of endocarditis, heart valve issues, aneurysms or poor kidney function (renal insufficiency).
• Have a permanent, implanted device to strengthen blood vessels and improve blood flow (vascular prosthesis).
• Have a weakened immune system.

How common is Q fever?

Q fever is very rare. Only around 200 cases are reported in the U.S. each year.

What are the symptoms of Q fever?

Initial (acute) symptoms of Q fever are flu-like and start three to 30 days after exposure. Some people continue to have symptoms for over a year after their initial exposure, called Q fever fatigue syndrome (QFS). Others develop symptoms of a more serious infection called chronic Q fever.

Symptoms of acute Q fever

Symptoms of acute Q fever are usually flu-like but can vary a lot. It might cause pneumonia, inflammation of your brain or its covering (encephalitis or meningitis) or inflammation in your liver (hepatitis). Symptoms you might experience include:

• Fever.
• Extreme fatigue.
• Chills.
• Sweats.
• Muscle aches.
• Sensitivity to light (photophobia).
• Severe headaches.
• Nausea and vomiting.
• Diarrhea.
• Cough.
• Chest pain.
• Stomach pain.
• Rash-like spots under your skin (purpura).
• Shortness of breath (dyspnea).

Symptoms of Q fever fatigue syndrome (QFS)

About 20% of people with Q fever will have fatigue and other symptoms that continue for months or years after initial exposure. Symptoms of Q fever fatigue syndrome include:

• Extreme fatigue.
• Headaches.
• Sweats.
• Joint pain.
• Muscle aches.

Symptoms of chronic Q fever (persistent Q fever)

Chronic Q fever starts months to years after your initial C. burnetii infection, even if you didn’t have symptoms at the time. While it most commonly affects your heart, heart valves and blood vessels, the symptoms can vary depending on what parts of your body are affected.

Symptoms of chronic Q fever include:

• Low-grade fever.
• Night sweats.
• Weight loss.
• Fatigue.
• Shortness of breath.
• Swelling of your legs or feet.

What causes Q fever?

The bacterium Coxiella burnetii causes Q fever. Animals — most commonly cattle, sheep and goats — can carry C. burnetii without symptoms. Bodily fluids (pee, poop, milk and birthing products like amniotic fluid) of infected animals can contaminate the soil, which people breathe in as dust or mist.

How does Q fever spread?

The most common way to get Q fever is through breathing in dust or mist contaminated with C. burnetii. This can happen if you live or work in an area where animals are kept, especially farm animals. Since C. burnetii can travel some distance in the air, you don’t have to have direct contact with animals to get it.

Less common ways to get Q fever include:

• Eating or drinking unpasteurized dairy products (like milk, cheese or ice cream).
• Getting bitten by an infected tick.
• Through pregnancy or during birth, from a pregnant person to their child.
• Through a blood transfusion.

Is Q fever contagious from person to person?

Q fever isn’t usually contagious. Rarely, there have been cases of a pregnant person transmitting Q fever to their child during pregnancy or birth.

How is Q fever diagnosed?

Your healthcare provider will diagnose Q fever by asking you about your symptoms and medical history and by taking a blood sample. They may also ask you if you live or work around animals.

Test results for C. burnetii can take several weeks. If your provider suspects you have Q fever, they might decide to treat you before the results come back.

How do you test for Q fever?

To test for Q fever, your healthcare provider will take a sample of your blood with a small needle. Your sample will be sent to a lab to look for signs of an infection with C. burnetii (testing for antibodies). They may also try to grow (culture) C. burnetii from your sample.

You may need to provide multiple samples over time to get a definitive diagnosis.

How is Q fever treated?

Acute Q fever is treated with antibiotics. Chronic Q fever is often treated with a combination of antibiotics and anti-inflammatory medications, but it can be hard to treat. Your provider will create a treatment plan based on your specific illness.

If you’ve been diagnosed with Q fever and have a history of heart valve or blood vessel conditions, talk to your provider about being treated proactively to reduce your risk of chronic Q fever.

What medications/treatments are used?

Your provider may prescribe:

• Doxycycline.
• Hydroxychloroquine.
• Trimethoprim-sulfamethoxazole (TMP-SMX).
• Rifampin.
• Fluoroquinolones (ciprofloxacin, ofloxacin).
• Clarithromycin.

Can Q fever be cured?

Yes, antibiotics can cure acute Q fever in most people. A small number of people with acute Q fever may have symptoms that last months or years, even with treatment. Chronic Q fever can be harder to cure.

How can I reduce my risk of Q fever?

Ways to reduce your risk of Q fever include:

• Wear a mask and gloves while handling animal fluids, especially birthing products.
• Don’t eat or drink unpasteurized dairy products.
• Some studies suggest that screening for and treating heart valve problems can prevent chronic Q fever in people who’ve been diagnosed with Q fever.
• If you have a high-risk job and live in an area where a Q fever vaccine is available (currently only in Australia), ask your provider about getting vaccinated.

Talk to your healthcare provider about avoiding Q fever if you live or work around farm animals and you’re at high risk for Q fever complications. This includes anyone with a history of heart valve or blood vessel conditions, pregnant people and those with a weakened immune system.

What can I expect if I have Q fever?

Symptoms of Q fever can last a long time (10 to 90 days), but most people make a full recovery. If you’ve been prescribed antibiotics, you can expect to take them for at least two weeks. About 1 in 5 people will have fatigue that continues for months or years (Q fever fatigue syndrome).

A small number of people (1 to 5%), usually those with underlying conditions, go on to develop chronic Q fever. If you have chronic Q fever, you’ll have to be treated for 18 months or longer.

Complications of Q fever

Both acute and chronic Q fever can cause complications, though they’re more common and usually more serious in chronic Q fever. Complications include:

• Weakened, bulging arteries (aneurysm).
• Arterial fistula, a condition that causes blood to flow incorrectly.
• Heart inflammation (endocarditis).
• Scarring in your lungs (fibrosis).
• Acute respiratory distress syndrome (ARDS).
• Heart failure.
• Bone infection (osteomyelitis).
• Pregnancy loss (miscarriage).
• Low birth weight.

Outlook for Q fever

The outlook for acute Q fever is usually good when treated with antibiotics. The mortality (death) rate for acute Q fever is 0.5 to 1.5%. Those who go on to develop chronic Q fever are at higher risk for complications and death. The mortality (death) rate for chronic Q fever is 12 to 25%.

How do I take care of myself?

If you’ve been diagnosed with Q fever, be sure to take any medications as prescribed. Ask your provider how to manage your symptoms and if there’s any way to reduce your risk of long-term symptoms or chronic Q fever.

When should I see a healthcare provider?

See your healthcare provider if you work or live around cattle, goats or sheep and you have symptoms of Q fever. If you have symptoms of chronic Q fever and could’ve been exposed to C. burnetii in the past (even if it was a long time ago), let your provider know.

What questions should I ask my doctor?

• Should I take preventative medications to reduce my risk of chronic Q fever?
• Should I be screened for heart and vascular issues?
• How do I take my medication?
• When should I follow up with you?
• What can I do to manage my symptoms?

A note from Cleveland Clinic

Q fever is a rare illness. If you work with or live near animals that might put you at risk, you can take precautions to reduce your chances of getting sick. While chronic Q fever only affects a small number of people, it can cause life-threatening complications. If you think you’ve been exposed to Q fever or if you have concerning symptoms, don’t hesitate to contact a healthcare provider. Let them know your health and work history to help them better understand your risks and provide the best treatment options.