Q fever is a zoonotic disease characterized by fever and rashes. A type of bacteria called Coxiella burnetii causes it. The first case of Q fever was identified in Queensland, Australia in 1935 and since then it was reported from many places across the world, except in cold areas such as parts of Scandinavia, New Zealand and Antarctica.
Q Fever Description:
The bacteria Coxiella burnetii tends to build-up in the udder and uterus of females of animals such as sheep, cattle, goats, horses, ticks, birds, cats, dogs and rabbits. As a result, bacteria can spread through contaminated milk or through placenta and amniotic fluid. Bacteria may also be present in urine and feces of the animals. Therefore, workers in milk plant, slaughterhouse workers, wool workers, farm workers, veterinarians, and workers in meat packing industry are at high risk of acquiring Q fever.
C. burnetii can also survive in dry dust for a long time. Therefore, individuals may become infected when exposed to dust contaminated by the female’s fluid. In addition, C.burnetii is also resistant to osmotic shock, disinfectants and UV rays. The infection rarely spreads from human to human. Further, C.burnetti has the potential to become an agent of bioterrorism and it is classified as Biosafety level 3.
Causes and Symptoms of Q fever:
Q fever may be caused when individuals
- drink contaminated milk
- eat contaminated meat
- undergo bone marrow transplantation
- inhale tiny droplets containing bacteria and/or
- inhale contaminated dust or aerosols
Q fever occurs in an acute and chronic form. The symptoms may show up within 3 to 30 days after infection. Individual infected with C.burnetti may show acute symptoms such as
- nausea and vomiting
- skin rashes
- heavy sweating
- cough and/or
Persons with Q fever may also show other symptoms such as
- liver inflammation (hepatitis)
- brain inflammation (meningoencephalitis)
- heart muscle inflammation (myocarditis)
- swelling of sac containing heart (pericarditis)
- inflammation of brain and spinal cord membrane and/or
Q fever can also occur in a chronic form in patients suffering from other medical conditions, including kidney disease, weak immune system, and damaged heart valves. Such individuals show mild symptoms of Q fever for a long time. The symptoms can be
- enlarged liver
- enlarged spleen
- mild fever and/or
Patients with chronic Q fever usually are diagnosed with endocarditis (inflammation of heart lining).
Diagnosis of Q fever:
It is difficult to diagnosis Q fever as it is mostly asymptotic in nature and most of the symptoms are similar to other conditions. However, tests such as Serology are used to diagnosis Q fever. The following Serology tests are used:
- ELISA (enzyme-linked immunosorbant assay)
- IFA (immunofluorescence assay)
- CF (complement fixation) and
Another method called DNA detection method (PCR-polymerase chain reaction) is also helpful.
Treatment for Q fever:
Acute Q fever is treated with drugs such as
- erythromycin and/or
The duration of treatment of acute Q fever is two to three weeks.
Chronic Q fever is treated with more than one antibiotic drug such as
- tetracycline and/or
The duration of treatment of chronic Q fever is at least three years. Post Q fever fatigue can be treated by taking 100mg of Minocycline per day for a period of two to three months.
Prognosis for Q fever:
Q fever itself is not fatal. However, complications may arise when the patient is suffering from other medical diseases. Moreover, once infected a person develops lifelong immunity against the disease.
Prevention of Q fever:
The precaution that should be taken is to avoid contact with the contaminated substances. The following precautions may be taken.
- pasteurizing the milk before using it
- wearing protective wear when working in high-risk industries
- disposing the birth fluids and other organs properly
- controlling the dust contamination in meat packing and wool industries
- mandatory vaccination for animals