[Q fever in Extremadura: an emerging infection]

Q fever (Coxiella burnetii infection) is an underdiagnosed zoonosis in our area, Extremadura, a rural region in the Southwest of Spain. The characteristics of Q fever and the changes in this infection seen over the last decade in our hospital are described.

A total of 124 cases of Q fever diagnosed in the Infectious Diseases Unit of a tertiary hospital Hospital Universitario Infanta Cristina de Badajoz) during the years 1992-2005 were analyzed. The epidemiological, clinical, serological and therapeutic data of the patients, and the factors related with hospital admittance are described.

Mean age was 41 +/- 16 years, most patients were males (4:1 ratio), 61% lived in rural areas and 47% mentioned some kind of contact with farm animals. The clinical presentation included non-focalized fever (53%), hepatitis (43%), pneumonia (11%), and endocarditis (6%). The factors related with the need for hospital admission were diagnosis after 1999 (OR: 12.2; 95% CI: 3.2-47.6), pneumonia (OR: 4.1; 95% CI: 1.1-15.9), and hepatitis (OR: 2.7; 95% CI: 1.2-6.3). During the second half of the study period there were more cases of Q fever, the interval of time to diagnosis was shorter (P = 0.042), and there was a significant increase in hospitalizations (55% versus 9%; P < 0.0001).

In Extremadura, Q fever is an emerging infection that predominates in males who are in contact with animals for work purposes. Non-focalized fever is the most frequent form of clinical presentation; pneumonia is rare. Hospitalization for Q fever infection has increased over the last years.