Q Fever

Abstract

SUMMARY Q fever is a zoonosis with a worldwide distribution with the exception of New Zealand. The disease is caused by Coxiella burnetii, a strictly intracellular, gram-negative bacterium. Many species of mammals, birds, and ticks are reservoirs of C. burnetii in nature. C. burnetii infection is most often latent in animals, with persistent shedding of bacteria into the environment. However, in females intermittent high-level shedding occurs at the time of parturition, with millions of bacteria being released per gram of placenta. Humans are usually infected by contaminated aerosols from domestic animals, particularly after contact with parturient females and their birth products. Although often asymptomatic, Q fever may manifest in humans as an acute disease (mainly as a self-limited febrile illness, pneumonia, or hepatitis) or as a chronic disease (mainly endocarditis), especially in patients with previous valvulopathy and to a lesser extent in immunocompromised hosts and in pregnant women. Specific diagnosis of Q fever remains based upon serology. Immunoglobulin M (IgM) and IgG antiphase II antibodies are detected 2 to 3 weeks after infection with C. burnetii, whereas the presence of IgG antiphase I C. burnetii antibodies at titers of ≥1:800 by microimmunofluorescence is indicative of chronic Q fever. The tetracyclines are still considered the mainstay of antibiotic therapy of acute Q fever, whereas antibiotic combinations administered over prolonged periods are necessary to prevent relapses in Q fever endocarditis patients. Although the protective role of Q fever vaccination with whole-cell extracts has been established, the population which should be primarily vaccinated remains to be clearly identified. Vaccination should probably be considered in the population at high risk for Q fever endocarditis.

Q-Fieber

“…Pneumonia and other clinical manifestations can occur. The chronic form is mainly characterized by endocarditis in pre- (Maurin und Raoult, 1999und 2002Anonymus, 2003;Woldehiwet, 2004). Zudem kann bei C. burnetii eine Antigenvariabilität festgestellt werden.…”

“…Gelegentlich treten Aborte, Totgeburten und die Geburt lebensschwacher Nachkommen auf. In den meisten Fäl-len verläuft die Infektion mit C. burnetii jedoch asymptomatisch (Maurin und Raoult, 1999und 2002.…”

“…Die Infektion kann aber auch über direkten Kontakt mit infizierten Tieren oder Tierprodukten z. B. beim Schlachten und nicht selten auch im Labor erfolgen (Hawker et al, 1998;Maurin und Raoult, 1999;Hatchette et al, 2001;Maurin und Raoult, 2002;Brouqui et al 2004;Sting et al, 2004;Tissot-Dupont et al, 2004). Die oral-alimentäre Infektion durch kontaminierte Roh-bzw.…”

“…Weitere Symptome des akuten Q-Fiebers sind Hepatitis und seltener Myokarditis, Peri-oder Endokarditis und weitere neurologische Manifestationen, wie Verwirrtheit, Meningitis, Meningoenzephalitis u. a. (Maurin und Raoult, 1999und 2002Kofteridis et al, 2004;Woldehiwet, 2004;Raoult et al, 2005). Kinder weisen weniger häufig als Erwachsene klinische Symptome auf (Maltezou und Raoult, 2002).…”

“…Beim akuten und chronischen Verlauf kann es durch Placentitis zu Frühgeburten, spontanen Aborten und Tod in utero kommen. Bei wiederholten Fehlgeburten ist chronisches Q-Fieber daher differentialdiagnostisch mit in Betracht zu ziehen (Maurin und Raoult, 1999Woldehiwet, 2004).…”