Q fever is an illness caused by the bacteria Coxiella burnetii, carried by animals (that are usually not unwell) such as cattle, sheep, goats, and kangaroos. People usually catch the infection by breathing in droplets or dust contaminated by birth fluids, faeces, or urine from infected animals. The bacteria can also exist in a variety of domestic and wild animal species, as well as in the general environment (e.g. dust and soil), which can also lead to infection and disease. Spread of infection from person-to-person is rare. Q fever can be treated with antibiotics.
Q fever is usually an acute (immediate) infection, but sometimes it can lead to a chronic (long-term) illness.
Many infected people have no symptoms. People who do become sick often have a severe flu-like illness. Symptoms begin about 2–3 weeks after exposure to the bacteria. However, this period can be as short as 4 days and as long as 6 weeks.
Typical symptoms of acute Q fever include:
• Fever and chills
• Severe sweats
• Severe headache (especially behind the eyes)
• Muscle pain
• Weakness and tiredness
• Weight loss.
Some patients may develop pneumonia (chest infection) and hepatitis (inflammation of the liver) during the course of acute illness. Most people make a full recovery and become immune to future Q fever infections.
Your doctor can diagnose Q fever based on symptoms, clinical examination, and laboratory tests on blood samples. Two or more blood samples on separate occasions are often required to confirm a Q fever diagnosis.
If given early, appropriate antibiotics can reduce the time for which people have Q Fever. Some people require admission to hospital. Chronic disease may require more than a year of antibiotics.
The bacteria are found in many animals including cattle, sheep, goats, dogs, cats, horses, pigs, rodents, camels, and kangaroos. The bacteria are also found in ticks. Infected animals usually have no symptoms; however, infection in animals may result in abortion, stillbirth, and infertility.
Infected animals have high numbers of bacteria in birth by-products such as the placenta and birth fluids. The bacteria can also be passed to the environment from faeces, urine, and milk of infected animals. The bacteria are highly infective and can survive in dust and soil for months and years.
- People most commonly catch the infection by breathing in droplets or dust containing the bacteria from birth fluids, faeces, urine, or blood of infected animals, such as during:
- Animal birthing
- Animal slaughtering/skinning/meat processing
- Shearing/wool processing
- Working with animal manure
- Transporting infected animals
- Veterinary/diagnostic procedures
- Infection can also occur through direct contact with infected animal tissue or fluids on broken skin - for example, through cuts with contaminated knives or needle-stick injuries when working with animals
- Consuming unpasteurised (raw) milk or milk products from infected animals may carry a risk of contracting the infection
- Ticks may very occasionally transfer the infection to people through tick bites, from breathing in tick excreta or through direct contact (e.g. removal of ticks from domestic animals, aerosol-generating activities such as shearing, or crushing ticks with bare hands)
- Person-to-person spread of infection is rare, but can occur through blood transfusion and mother-to-baby transmission.
Who is at risk?
People whose work exposes them to high risk animals, animal products, and animal excreta may develop Q fever. These high-risk occupations include:
- Abattoir and meat workers
- Agriculture, livestock and dairy farmers and workers
- Stockyard/feedlot workers and transporters of animals, animal products and waste
- Shearers, wool classers/sorters, pelt and hide processors
- Knackery workers
- Tannery workers
- Laundry workers handling clothing from at-risk workplaces
- Pet food manufacturing workers
- Veterinarians, veterinary nurses/students/researchers, and others working with veterinary specimens
- Agriculture college staff and students working with high risk animals
- Animal shooters/hunters
- Laboratory personnel working with materials containing the bacterium Coxiella burnetii
- Wildlife/zoo workers, animal trainers
- Dog/cat breeders, and anyone regularly exposed to pregnant or birthing animals.
Other people at risk of Q fever through environmental exposures include:
- Family members of the high risk occupational groups described above, through exposures to contaminated clothes, boots or equipment
- People living on or in close proximity to a high-risk industry (e.g. neighbouring livestock farms, stockyards housing cattle/sheep/goats, meatworks, land being fertilised by untreated animal manure)
- Visitors to at contaminated environments (e.g. farms, abattoirs, animal saleyards)
- People living near livestock transport routes who may be exposed to contaminated dust from the passing animals
- People involved in mowing which stirs up dust contaminated by animal excreta, in areas where there are livestock or native animals, commonly kangaroos
- People who observe or assist animal births.
A Q fever vaccine is available to protect people against the disease. Vaccination is recommended for all people who are working in, or intend to work in, a high-risk occupation (see Who is at risk?). High risk workplaces should have a vaccination program to protect their workforce.
People at risk of Q fever through non-occupational, environmental exposures (see Who is at risk?) are also recommended for vaccination.
People must be screened and tested before they are vaccinated against Q fever. Check the Australian Q fever Register (www.qfever.org) to find a doctor specifically trained for Q fever vaccination services.
Apart from vaccination, people can take steps to reduce the risk of Q fever to themselves or the community, including:
- Washing their (or their children’s) hands and arms thoroughly in soapy water after any contact with animals
- Wearing a P2 mask (particulate respirator, available from pharmacies and hardware stores) and gloves when handling and disposing of animal products, waste, placentas, and aborted fetuses
- Preventing animals from eating placenta and immediate removal of animal abortive and birth materials, with safe disposal by deep burial – do not use them in compost
- Personal protective equipment and contaminated clothing should be removed at the site, and appropriately bagged and washed on site, to reduce the risk of exposing non-vaccinated individuals and family members outside of the workplace to Q fever
- Appropriate treatment of animal manure: do not remove manure from deep litter sheds or yards for at least one month after birthing season; compost manure or alternatively store manure for three months prior to spreading on farm land for fertiliser
- Manure should be covered during storage and transport and must be under-ploughed immediately when spreading on farming land
- Minimising dust and aerosols in slaughter and animal housing areas.
Most people make a full recovery from Q Fever. However, in about 10 to 20% of people, chronic fatigue (post Q fever fatigue syndrome) is still present after 12 months, affecting an individual's ability to work at full capacity Occasionally people may develop chronic infections that affect the heart, bones, or joints. Persons at increased risk for chronic Q fever after acute infection include: immunosuppressed persons (e.g. cancer patients with chemotherapy, patients with organ transplantation), pregnant women, and persons with heart valvular abnormalities.
If you work with potentially infectious animals or materials, check with your employer to see if they have a Q Fever vaccination program. People requiring Q Fever immunisation will need to purchase the vaccine unless it is provided by their employer. To find out where you can be immunised against Q Fever, check providers listed on the Australian Q Fever register. For further assistance, please contact your doctor or nearest public health unit.