Q Fever: Origin, Risk Factors And Symptoms

In most cases, Q fever is a disease that can be treated without complications. However, some people develop severe symptoms that can even turn into hepatitis, pneumonia, endocarditis, or meningitis.

Q fever is the name given to a disease caused by bacteria that spread from animals to humans. It was first detected in 1935 and was given the name Q fever because it was not possible to establish an origin early. The letter “Q” comes from ” query “, in other words, ” in consultation “.

Upon investigation, it was discovered that the causative agent of Q fever was the bacteria Coxiella burnetii . The latter initially lodges in domestic animals such as cows, goats, sheep and other mammals. However, in animals, it usually does not trigger any health problems.

Although Q fever can occur at any time of the year, it has been observed to present mostly in the spring and the early summer months. The greatest number of cases occurs between April and May.

Origin of Q fever

Usually, Q fever is a mild illness similar to the flu. However, there is also a fatal form of this disease which causes damage to the brain, heart, liver and lungs. However, other people have no symptoms.

The bacterium Coxiella burnetii , which causes the disease, is mainly found in the birth organs of animals. That is, in the placenta and amniotic fluid. We also find it in the milk, urine, and faeces of infected animals.

Some people are even infected without direct contact with animals. It is sufficient to inhale dust that has been contaminated by the animal’s stool, urine or infected birthing organs. In addition, the bacterium is transmitted through the consumption of unpasteurized milk, extracted from carrier animals.

Characteristics and symptoms

It is estimated that out of 10 people who contract the bacteria, only 5 will show symptoms. Usually symptoms appear 2-3 weeks after exposure to bacteria. The most common manifestations of the disease include:

• Fever with chills and sweat
• Headache and muscle pain
• Nausea, vomiting and / or diarrhea
• Tired
• Pain in the chest and / or abdominal pain
• Dry cough
• Weightloss

All of these symptoms can be mild or severe. If the infection lodges in the lungs or liver, it can lead to pneumonia or hepatitis, respectively. On the other hand, if a pregnant woman contracts the disease, there is a risk of miscarriage.

Just under 5 in 100 people develop chronic Q fever. This happens months or even years after the initial infection. This is a serious problem that can be fatal because it is usually caused by infection of one or more valves in the heart.

Risk factors for Q fever

There is no doubt that the bacteria are present in some pets. However,  its presence has also been detected in some wild animals as well as ticks. The main risk factor is therefore direct or indirect contact with all these animals.

Obviously,  those most at risk of contamination are farm workers, or slaughterhouse workers, as well as veterinarians, researchers and food processors. In addition, it was found that men were more likely to contract the disease than women.

The vast majority of cases of Q fever occur in people between the ages of 30 and 70. Indeed, it is very rare that this disease appears in children. At first, it manifests with symptoms of pneumonia.

Other interesting facts

The risk of developing the disease in its chronic form is much greater for people with:

• History of heart valve problems
• Abnormalities in the blood vessels
• Weak immune system
• Pregnant women

At the moment,  no vaccine is available against Q fever. Therefore, it is best to take preventive measures. For the general community, it is fundamental not to consume unpasteurized milk from any animal.

Finally, those who work with animals or live on farms should be aware and attentive to any manifestation of this disease and then seek medical attention in case symptoms appear. On the other hand, people in the high risk group should not be in contact with animals.