Q Fever

Q fever, also referred to as Query fever, is classified as a bacterial infection that can be triggered by Coxiella burnetti. The bacteria that causes the infection is most common in sheep, goat, and cattle.

Humans can generally be exposed to Q fever when the bacteria is inhaled through contaminated dust. Veterinarians, farmers, and people who deal with animals exposed to the bacteria are at a huge risk of getting infected.

The symptoms exhibited by the disease are very identical to the flu. Nevertheless, some individuals show no signs at all. Even without treatment, mild forms of the infection may still be able to clear up within a few weeks.

On rare occasions, severe forms of Q fever may develop if the case is severe. This means that it may persist for up to 180 days or more. If the infection becomes persistent, a severe form of Q fever may develop.

Individuals with heart issues or weakened immune systems are at higher risk of getting infected. A chronic form of Q fever can cause severe damage to a person’s vital organ, such as:

  • Brain
  • Lungs
  • Heart
  • Liver

More chronic forms of Query fever can be managed with antibiotics. People at risk of the fever can suppress the disease by thoroughly washing their hands and sanitizing contaminated areas.


The symptoms of Q fever do not manifest until about 14 to 20 days after being exposed to the bacteria. Notwithstanding, a person can become infected and not show any signs. Symptoms can be different from one person to another.

General symptoms of mild Query fever may include:

  • A high fever
  • Sweats or chills
  • Nausea
  • Abdominal pain
  • Jaundice
  • Muscle pain
  • Shortness of breath
  • A cough
  • Chest pain when inhaling
  • A headache
  • Clay-coloured stools
  • Diarrhoea

Although it is not common, rashes can also be a common symptom.


The bacteria that causes Query fever is called Coxiella burnetii. These bacteria are commonly found in cattle, goats, and sheep. These animals can spread the bacteria in:

  • Milk
  • Faeces
  • Fluids from giving birth
  • Urine

The above substances can get stored in the barnyard in areas where contaminated dust float in the air. Infection can happen when humans get exposed to Q fever by breathing in the contaminated air.

On rare occasions, humans can also get infected by ingesting unpasteurized milk. Human to human infection hasn’t been recorded yet, and the rate of infection of the bacteria is unknown since most cases are not reported.

Who is at risk of Q fever?

Because the bacteria commonly infect goats, cattle, and sheep, individuals who are at highest risk of getting infected include:

  • People who work at meat processing facilities
  • Farmers
  • People who work at research laboratories and handle livestock
  • People who work at research laboratories with samples of C. burnetii
  • Individuals who stay close to farms
  • Veterinarians
  • People who handle sheep
  • individuals who work in the dairy industry


Diagnosing Q fever based on symptoms alone can be very challenging. Doctors may have to analyze your working or living environment and check for any complications or flu-like symptoms before diagnosing a person with Q fever.

Doctors can also run a blood antibody test to correctly diagnose anyone with the infection. According to the CDC (Centers for Disease Control), an antibody test can commonly appear negative in the first week to two weeks of infection.

Extensive tests may be required if your doctor suspects any chronic infection. These tests may include an x-ray or echocardiogram to look check for any signs of chronic complications properly.


In most cases, Q fever can become persistent even after treatment. A person can become experience an extreme case of Q fever if any of the following organs are affected:

You are at an increased risk of developing a severe case of Q fever if you:

  • Are pregnant
  • Have a weakened immune system
  • Have an existing heart valve complication
  • Have abnormalities in the blood vessel

The CDC maintains that extreme cases of Query fever occur in less than 5% of infected patients. Reported cases of complicated Q fever affect the heart, and it is known as bacterial endocarditis.

Endocarditis occurs as an inflammation of the heart valves and inside lining of the heart chambers, which is referred to as the endocardium. Conditions like this can damage the heart valves, which can be fatal if left untreated.

Other extreme complications that are also less common include:

  • Pneumonia or other lung complication
  • Pregnancy issues such as miscarriage, premature birth, low birth weight, and stillbirth
  • Hepatitis
  • Meningitis


Treatment of Q fever depends on how severe the symptoms of the condition is.

Mild infection

Without any treatment, milder forms of the fever may resolve within a few weeks.

Severe infection

Your healthcare provider may administer an antibiotic to help with the fever. One common antibiotic that is used is by children and adults with a severe case of Q fever is doxycycline.

It is crucial to take treatment seriously if you suspect the symptoms are getting more serious, even before the result of the lab test is out.

The standard duration of treatment may last for up to 14 to 21 days, and symptoms may subside within three days. Failure to respond positively to doxycycline could mean you are treating the wrong complication.

Chronic infection

Doctors may administer antibiotics for 18 months if the case of Q fever is chronic. This may include further tests to rule out other forms of infections.


Luckily, Australia has successfully produced a vaccine for people working in high-risk environments.

The following steps should be taken if you’re not vaccinated and you potentially exposed to Q fever:

  • Properly decontaminate and disinfect exposed areas
  • Quarantine exposed and infected animals
  • Routinely test animals for infection
  • Properly have your hands washed
  • Control the airflow from barnyards and animal holding facilities to other areas
  • Ensure to have the milk you drink pasteurized
  • Properly dispose of birth materials after a livestock animal has given birth


Fortunately, antibiotics are generally very effective, and death from the fever is very uncommon. Nevertheless, patients with endocarditis require an early diagnosis. Antibiotics should also be administered for at least 18 months for a positive result.