In Q fever (synonyms: Australian Q fever; Balkan fever; Balkan flu; Derrick-Burnet disease; Euboea fever; Coxiella burnetii infection; Rickettsia burnetii infection; Cretan fever; Cretan pneumonia; Mossmann disease; Olympus disease; Query fever; Slaughterhouse fever; Slaughterhouse fever; Seven-day fever; Southeastern flu; Desert fever; ICD-10 A78) is an infectious disease caused by the gram-negative bacterium Coxiella burnetii, from the family Rickettsiaceae.
The disease is one of the bacterial zoonoses (animal diseases).
Cattle, sheep and goats, but also cats, dogs, rabbits, wild animals and birds are the main reservoirs. Coxiella burnetii is also frequently found in flies, ticks, lice and the like.
Occurrence: Infection occurs worldwide except in Antarctica and New Zealand.
Contagiousness (infectiousness or transmissibility of the pathogen) is very high; fewer than 10 pathogens are required for aerogenic infection in humans. Coxiella burnetii shows high resistance (resilience) to desiccation and to physical and chemical agents.
Transmission of the pathogen (route of infection) is aerogenic, i.e., through inhalation of infectious dust (even over long distances), but can also occur through direct contact with the infected animal. Newborn animals are highly infectious. Transmission through food such as raw milk products is possible in principle.
Human-to-human transmission: Yes, but rare.
Incubation period (time from infection to onset of disease) is 2-29 days (average 3 weeks). However, the incubation period depends on the amount of pathogen ingested and the route of infection.
Acute infection can be distinguished from chronic (rare) infection.
Sex ratio: males are slightly more commonly affected than females.
The incidence (frequency of new cases) is approximately 0.1-0.5 cases per 100,000 inhabitants per year.
The disease leaves a long-lasting immunity, but it can be reactivated under certain circumstances if the pathogens survive in macrophages (scavenger cells).
Course and prognosis: The disease takes a flu-like, mild course in about 50% of cases and heals spontaneously (by itself) after 1-2 weeks. However, complications such as pneumonia or, rarely, hepatitis may occur. Infections during gravidity (pregnancy) can lead to abortion (miscarriage) or premature birth.Untreated, the overall lethality (mortality based on the total number of people with the disease) is < 2%.The chronic form (occurs in about 1% of cases) usually manifests as endocarditis (inflammation of the inner lining of the heart). Coxial endocarditis is fatal in 4% of cases within 3 years.
A vaccination against Q fever is not yet available in Germany.
In Germany, direct or indirect pathogen detection is reportable according to the Infection Protection Act (IfSG) if it indicates an acute infection.
