From the Guidelines
Testing for Q fever is recommended for individuals with symptoms suggestive of the infection who have risk factors for exposure to Coxiella burnetii, such as those with occupational exposure to livestock, including veterinarians, butchers, slaughterhouse workers, farmers, and laboratory workers, as well as those living in rural areas or near farms with livestock 1.
Key Considerations for Testing
- Individuals with unexplained fever, pneumonia, or hepatitis who have been exposed to livestock, particularly cattle, sheep, or goats, should be tested for Q fever 1.
- Testing should also be considered for individuals who have consumed unpasteurized dairy products or have been in areas with known Q fever outbreaks 1.
- Pregnant women with potential exposure to Q fever should be tested due to the increased risk of complications 1.
Diagnostic Tests
- The primary diagnostic tests for Q fever include serological tests, such as immunofluorescence assay or ELISA, to detect antibodies against C. burnetii 1.
- PCR testing of blood or tissue samples can also be used during early infection 1.
Importance of Testing
- Early diagnosis of Q fever allows for appropriate antibiotic treatment, typically with doxycycline 100 mg twice daily for 2-3 weeks in acute cases, preventing progression to chronic infection which can lead to serious complications like endocarditis 1.
- Prompt diagnosis and treatment can shorten the illness and reduce the risk of severe complications 1.
From the Research
Individuals at Risk of Q Fever
The following individuals should be tested for Q fever:
- Shepherds, cattle farmers, and veterinarians, as they have a high risk of C. burnetii infection due to frequent animal contact 2
- People working with animal birth products, as they can be infected with Q fever 2
- Individuals who have been exposed to infected aerosols, as infection usually occurs through inhalation 3
- People with symptoms of acute Q fever, such as mild flu-like illness, gastrointestinal symptoms, and rash 3
Occupations with Lower Risk
- Obstetricians and midwives, as there is no increased risk for people working in an obstetric department 2
- Office employees, as they have a lower seroprevalence of Q fever compared to individuals with frequent animal contact 2
Diagnostic Techniques
- Indirect immunofluorescence assay (IFA) is a suitable method for diagnosing Q fever and its therapeutic follow-up 4, 5, 6
- Enzyme-linked immunosorbent assay (ELISA) can be used as a screening assay for acute Q fever, with high sensitivity and specificity 5
- Complement fixation test (CFT) has a good specificity but poor sensitivity, especially for phase I antibodies 6