Q Fever

Q fever is a bacterial infection caused by the coxiella burnetii bacteria.

Q fever is spread to humans from animals, most commonly livestock such as sheep, goats and cattle. Very rarely, it can spread directly from human to human, usually during sexual intercourse.

The ‘Q’ in Q fever stands for ‘query’. This is because when the infection was first indentified, its cause was unknown. The cause is now understood and the name has remained the same.

Types of Q fever

There are two main types of Q fever:

• acute Q fever, which is the most common and least serious type, and
• chronic Q fever, which is less common but more serious.

Acute Q fever

The most common symptoms of acute Q fever are flu-like symptoms, such as muscle pain and fever. Less commonly, acute Q fever can cause mild pneumonia (inflammation of the lungs), and mild hepatitis (inflammation of the liver).

Chronic Q fever

The most common symptom of chronic Q fever is inflammation of the inner lining of the heart. This is known as endocarditis.

Endocarditis is potentially very serious. Left untreated, it can affect the normal workings of the heart and lead to heart failure.

How common is Q fever?

Q fever is most common in Australia and the south of France, although cases have been reported throughout the world.
 
In the UK, around 70 cases of Q fever are reported every year. However, the actual figure may be much higher because Q fever often causes only mild symptoms which can be mistaken for flu.

Risk groups

In England, people who are most at risk of getting Q fever are those whose occupation brings them into close contact with livestock, including:

• farmers,
• stablehands,
• abattoir workers, and
• meat packers.

Outlook

The outlook for acute Q fever is good. Most people fight off the infection after a few weeks, without the need for treatment. However, antibiotics are recommended as they can help to relieve symptoms within a few days.

The outlook for chronic Q fever depends on whether antibiotic treatment is available. Without treatment, the condition is usually fatal. With treatment, the outlook is moderately good with an estimated mortality (death) rate of less than 10%.

Many people with chronic Q fever need to take antibiotics for many years to prevent the infection from recurring.

Vaccination

A vaccination for Q fever has been produced in Australia but has not been licensed for use in England.  

However, the Health and Safety Executive is currently working with the Joint Committee on Vaccinations to determine whether a routine vaccination should be made available to people in high-risk occupations.