Author: Vanessa Mora
Editor: Leah Farquharson
Overview
Query Fever (Q Fever) is an infectious disease caused by a bacteria called Coxiella burnetti (Dupont & Raoult, 2008). This bacteria is mainly found in domestic cattle, sheep and goats, however it can also be present in dogs, cats, pigs, camels, wild birds and rodents (Maurin & Raoult,1999). Ingestion and inhalation result in the bacteria to enter the blood, where life threatening symptoms may occur (Patil & Regunath, 2020).
What Causes Query Fever?
Humans are exposed to Query Fever when animals release the Coxiella burnetti bacteria in urine, feces, wool, milk and pregnancy fluids (Dupont & Raoult, 2008). These contaminated products may be present in the air and may infect humans via inhalation, or can be ingested through the consumption of raw milk products (Gürtler et al., 2014).
Although rare, transmission from person to person is also possible through contact with infected women who are about to give birth (Porter et al., 2011). This bacteria is resistant to extreme conditions, which allows it to survive in the environment as well as in humans for long periods of time (Porter et al., 2011).
Symptoms
Half of the patients have no symptoms. However, after 3-30 days, symptoms may include the following:
- Chest pain and Cough,
- Diarrhea,
- Fever and chills,
- Fatigue,
- Headache,
- Muscle pain,
- Nausea and Vomiting,
- Pneumonia ( Maurin & Raoult, 1999)
Risk Factors
Risk factors that increase the likelihood of acquiring Query Fever include:
- Absence of a mask and protective clothing in workplaces that have close contact with domestic animals and dairy products,
- Having an impaired immune system,
- Pregnancy,
- Occupations such as farmers, veterinarians, abattoir workers, and laboratory personnel ( Maurin & Raoult, 1999).
Diagnosis
A physical examination will be performed by acquiring the patient’s exposure history including:
- Contact with domestic animals
- Consumption of raw milk products
- Any recent travel to rural areas with greater risk of Q fever
- The patients current symptoms.
If the patient notes any of the symptoms listed above the physician will perform further tests and diagnosis (Maurin & Raoult,1999).
Physicians may perform blood tests after transmission to detect if the Coxiella burnetii bacteria is present (Patil & Regunath, 2020). A chest x-ray may be performed if symptoms suggest pneumonia and an echocardiogram may also be performed to note if the patient has any heart valve issues (Patil & Regunath, 2020).
Treatment
Query fever is treated using antibiotics (doxycycline and hydroxychloroquine) for at least 18 months (Maurin & Raoult, 1999). Patients whose echocardiogram demonstrated heart valve issues may require valve replacement surgery in addition to antibiotic treatment (Maurin & Raoult, 1999).
References
Frankel, D., Richet, H., Renvoisé, A., & Raoult, D. (2011). Q fever in France, 1985-2009. Emerging infectious diseases, 17(3), 350–356. DOI: 10.3201/eid1703.100882.
Gürtler, L., Bauerfeind, U., Blümel, J., Burger, R., Drosten, C., Gröner, A., Heiden, M., Hildebrandt, M., Jansen, B., Offergeld, R., et al. (2014). Coxiella burnetii – Pathogenic agent of Q (query) fever. Transfusion medicine and hemotherapy : offizielles Organ der Deutschen Gesellschaft für Transfusionsmedizin und Immunhämatologie, 41(1), 60–72. DOI: 10.1159/000357107.
Kersh G. J. (2013). Antimicrobial therapies for Q fever. Expert review of anti-infective therapy, 11(11), 1207–1214. DOI: 10.1586/14787210.2013.840534.
Maurin, M., & Raoult, D. (1999). Q fever. Clinical microbiology reviews, 12(4), 518–553. DOI: 10.1128/CMR.12.4.518.
Porter, S. R., Czaplicki, G., Mainil, J., Guattéo, R., & Saegerman, C. (2011). Q Fever: current state of knowledge and perspectives of research of a neglected zoonosis. International journal of microbiology, 2011, 248418. DOI: 10.1155/2011/248418.
Tissot-Dupont, H., & Raoult, D. (2008). Q Fever. Infectious Disease Clinics of North America, 22(3), 505-514. DOI: 10.1016/j.idc.2008.03.002.