Q fever: epidemiology, clinical features and prognosis. A study from 1983 to 1999 in the South of Spain Arı ´stides de Alarco ´n a, *, Jose Luis Villanueva a , Pompeyo Viciana a , Luis Lo ´pez-Corte´s a , Rafael Torronteras b , Ma ´ximo Bernabeu a , Elisa Cordero a , Jero ´nimo Pacho ´n a a Service of Infectious Diseases, University Hospitals Virgen del Rocı ´o, Sevilla, Spain b Service of Microbiology, University Hospitals Virgen del Rocı ´o, Sevilla, Spain KEYWORDS Q fever; Epidemiology; Prognosis Summary Objectives. Clinical polymorphism is a main feature of Q fever and, depending upon the geographic location, differences in its clinical picture have been described. The objective of this study was to determine the epidemiology, clinical features and prognosis of acute Q fever in our area. Methods. From 1985 to 1999, consecutive cases of Q fever, presented as febrile syndrome and attended in a tertiary teaching hospital in Sevilla, Spain, were included and followed prospectively. Results. Two hundred and thirty-one cases of acute Q fever were included. A non- focalized febrile syndrome lasting from 7 to 28 days (fever of intermediate duration) was the most frequent presentation (n ¼ 208, 90%). One hundred and forty-eight patients had hepatitis. Overall, 53% of the cases were urban and contact with animals was referred in 39% of the patients. No relationship between clinical presentation and possible route of infection was observed. Prognosis was excellent (100% cured), although in 18 patients fever was prolonged more than 28 days and three patients developed life-threatening organ affection. Antimicrobial treatment was more effective if it was administered in the first two weeks (median defervescence of fever: 3 days versus 5.5 days, p , 0:01). Conclusions. Acute Q fever is a common cause of fever of intermediate duration, even in urban areas. Elevation of hepatic enzymes was the most frequent laboratory finding. Severe organ affection is uncommon and the overall prognosis of the disease is excellent. Early treatment seems to shorten the duration of the disease. Q 2003 The British Infection Society. Published by Elsevier Science Ltd. All rights reserved. Introduction Q fever is a worldwide zoonosis caused by Coxiella burnetii, a small gram-negative microorganism that grows exclusively in the phagolysosomes of eukary- otic cells. It was originally described by Derrick in Queensland, Australia as an acute febrile illness among abattoir workers. 1 Since 1945, the disease has been reported from many parts of the world although most cases originate from the United Kingdom, Canada, Australia and France. 2–5 Clinic polymorphism is a main feature of Q fever. Journal of Infection (2003) 47, 110–116 www.elsevierhealth.com/journals/jinf 0163-4453/03/$ - see front matter Q 2003 The British Infection Society. Published by Elsevier Science Ltd. All rights reserved. doi:10.1016/S0163-4453(03)00013-6 *Corresponding author. Tel.: þ34-955-012375; fax: þ 34-955- 012377. E-mail address: aristide@cica.es