Q fever (Query fever) is a disease that spreads from animals to humans. It is caused by a bacterium called Coxiella burnetii.
This microorganism can live in its spore form for months and even years in dust or soil. It is found all over the world.
Animals like goats, sheep and cattle can carry the Q fever bacteria in their flesh and body fluids. The highest levels of these bacteria are found in tissues involved in birth - the uterus, placenta, and birth fluids. People usually get infected by breathing in dust contaminated by these tissues.
The infection is usually not serious and resolves on its own, but it can be treated with antibiotics, if needed.
Q fever can feel like an acute viral illness. If someone is infected, symptoms typically appear in two to three weeks, and include:
- rapid onset of fever
- chills
- headache
- weakness
- malaise (a general sick feeling)
- severe sweats
People usually get Q fever when they breathe in contaminated dust. It is very infectious, and it only takes a few microorganisms to cause infection.
Infection can occur through contact with infected animals and contaminated materials. People may also get Q fever by drinking unpasteurized, infected milk. It rarely, if ever, spreads from person to person.
Q fever can affect anyone who works outdoors or has contact with infected soil or dust. Airborne Q fever bacteria may be carried a kilometre or more downwind. It also spreads from room to room easily in farm buildings and laboratories housing infected animals.
Some people are at higher risk for Q fever including:
- farmers, farm workers, and ranchers
- stockyard workers
- livestock truck drivers
- people who service livestock trucks
- visitors to animal auctions
- meat packers
- rendering plant workers
- hide and wool handlers
- hunters and trappers
- animal researchers and support staff
- workers who care for pets and livestock - veterinary personnel, and zoo attendants
- health care workers who have contact with aerosolized fluids from people infected with Q fever
In most cases, the illness lasts less than two weeks and does not require treatment. Complications of this disease are rare and are more likely to happen with people who have weakened immune systems and pregnant people. These complications include:
- inflammation of the lungs (pneumonia)
- neurologic problems
- inflammation of the heart
- liver disease and jaundice
- miscarriage, poor fetal growth, and premature labour in pregnant people
The fatality rate for untreated cases is less than one per cent.
In small number of cases (1-5%), Q fever can cause illness months to years after the initial infection. This condition, known as chronic Q fever, is more common in people with a heart valve condition, a vascular abnormality, weakened immune system, are over 50 years of age, or are pregnant. Chronic Q fever can cause infection of the heart, large blood vessels, bones, and joints.
Diagnosis of Q fever is done usually by blood testing, and sometimes, tissue samples.
Q fever can be treated with antibiotics.
Take proper precautions when handling livestock and other animas to prevent Q fever, including:
- Appropriately dispose of all birthing products, including placentas, fetal membranes, and aborted fetuses (birthing products should be disposed of by incineration or burial, as permitted). Dogs, cats, birds and other animals should not be allowed to scavenge birthing products
- If possible, kidding should not take place outdoors
- Separate indoor facilities should be appointed for birthing, where possible
- Restrict access to barns and laboratories used in housing potentially infected animals
- Use only pasteurised milk and milk products
- Quarantine imported animals. The management of infected animals is important. Because infected animals do not show symptoms, animals should be routinely tested for antibodies to this organism, and measures should be taken to prevent airflow to other occupied areas
- Use protective clothing, gloves and masks while working with these animals (especially pregnant ones)
- Properly decontaminate surfaces with formalin or bleach solutions
- Properly dispose of contaminated waste
- Pregnant people should not help with the birthing of livestock
- When visiting farms, livestock auctions or shows, careful sanitation regarding hands, footwear, trucks and transport trailers etc., is recommended
