Q fever: symptoms, who is at risk and how it is treated in the UK

Q fever is an infection with the bacterium Coxiella burnetii. UKHSA explains that it causes illness, and sometimes abortion, in animals, and can lead to a pneumonia-like illness in humans. It is usually, but not always, caught by direct contact with farm animals, especially sheep, cattle and goats.

The NHS says Q fever is rare, which is why most people in the UK will never encounter it. UKHSA adds that most cases are sporadic, and that outbreaks are unpredictable and more likely to affect urban, non-immune populations.

It is called a zoonosis, an infection that passes from animals to people.

The NHS says Q fever is most often spread to humans by close contact with infected farm animals. The bacteria can be spread by contact with afterbirth (the placenta), blood, pee, poo, and animal skins, fur and wool, and can pass by being breathed in or through touch. People can also get Q fever by drinking unpasteurised milk, although this is less likely.

People who work closely with animals are more at risk, such as farmers, vets, stablehands and abattoir workers. UKHSA describes it as mainly an occupational disease linked to rural employment, and says that prevention and control measures are most effective for occupational groups and environments, such as restricting access to potentially infected animals and disposing of animal birth products safely.

The NHS says Q fever does not always cause symptoms. Some people get flu-like symptoms within 2 to 3 weeks of being infected: a high temperature, aching muscles, tiredness, feeling sick, a sore throat and swollen glands. Symptoms usually last up to 2 weeks.

Because these symptoms are common to many illnesses, the exposure history matters. Someone with flu-like illness who has recently worked with lambing ewes, cattle or goats, or has drunk unpasteurised milk, should mention it to their GP.

• High temperature and aching muscles.

• Tiredness and feeling sick.

• Sore throat and swollen glands.

• Often no symptoms at all.

The NHS advises seeing a GP if you think you have Q fever and you are pregnant, because Q fever can cause miscarriage and serious complications if it spreads to your baby, especially if you catch it early in pregnancy; if your immune system is weakened, for example after an organ transplant or during chemotherapy, because the infection may affect your eyes or brain; or if you have heart valve disease.

It says Q fever is usually harmless but in rare cases can lead to serious problems, so anyone in these groups who is worried should seek advice rather than wait.

The NHS says that if a GP thinks you might have Q fever, they can arrange a blood test to see if you have been infected. If you are pregnant and test positive, a GP can refer you for more tests to see whether your baby has been infected, which is very rare. UKHSA says its Rare and Imported Pathogens Laboratory is a specialist centre that provides advice and diagnosis for unusual infections including Q fever.

If symptoms are severe or not getting better, the NHS says a GP may prescribe a course of antibiotics for 1 or 2 weeks, and that it is important to finish the whole course even if you start to feel better.

In a few people, the NHS says, symptoms can last for months, which is known as chronic Q fever. Chronic Q fever sometimes leads to serious heart problems such as endocarditis, and people with it may need a much longer course of antibiotics and treatment in hospital for any complications that develop. UKHSA says chronic disease is where symptoms persist for more than 6 months and that endocarditis, an infection of the heart valves, may rarely occur.

UKHSA also notes that acute Q fever in pregnancy, with or without symptoms, can occasionally cause premature birth, low birth weight or abortion, and that infection acquired in pregnancy is usually without symptoms in the mother, though chronic infections can become apparent and put further pregnancies at risk.

The NHS advises people who work with animals to wash their hands regularly, clean cuts or grazes immediately and cover them, wear protective clothing such as waterproof gloves and goggles, and make sure all animal afterbirth is cleaned up safely. It advises not helping animals give birth if you are pregnant, not touching anything that has been near animal blood, poo, pee or afterbirth, not drinking unpasteurised milk and not eating in areas where animals are kept.

If you are pregnant it is especially important to avoid contact with sheep and lambs during the lambing season, between January and April, because if you catch Q fever in pregnancy you will usually have no symptoms. The NHS adds that there is also a risk of toxoplasmosis from sheep and lambs during lambing season. UKHSA advises that pregnant women, people with suppressed immune systems, and people with congenital or acquired heart valve disease or vascular grafts should avoid contact with cattle, sheep, goats and cats while the animals are pregnant.

Q fever is diagnosed through GP blood tests and specialist reference laboratories, with UKHSA providing guidance. UKHSA also points to HSE guidance on protecting farmers and farm workers from zoonoses and to advice for pregnant women who are in contact with animals.

The practical points, whichever service you use, are to mention animal exposure to the clinician and, for higher-risk groups, to see a GP early.