The Many Faces of Sporadic Acute Q Fever, Gran Canaria: Canary Islands (Spain) (1998–2024)

Abstract

Coxiella burnetii is an intracellular bacterium responsible for an anthropozoonosis that can be asymptomatic or manifest as acute or chronic Q fever. This extensive series of 588 patients represents one of the largest single-center studies on sporadic acute Q fever, highlighting the Canary Islands as a high-incidence region in Spain. Epidemiologically, the domestic cycle is the primary driver of infection, with caprine livestock serving as the main reservoir, showing a local prevalence of 60.4%. Transmission is predominantly airborne via aerosols; the environmental resilience of C. burnetii facilitates its transport into urban areas, where the majority of patients reside despite lacking direct animal contact. While fever, headache, and diaphoresis are hallmark symptoms, over 90% of patients exhibit transient urinalysis abnormalities, a finding that often leads to misdiagnosis and inappropriate antimicrobial use. Clinically, the non-specific (45.7%) and hepatic (44.1%) forms are most prevalent, whereas the pulmonary form (7.8%) is strongly associated with smoking and alcohol consumption. Although localized forms affecting the nervous system or skin (such as panniculitis) were observed, the overall prognosis remains excellent with no progression to chronic Q fever in this series. In summary, the extensive series described characterizes acute Q fever patients in the Autonomous Community of the Canary Islands, with features that are similar in some cases but also show notable differences compared to other national and international series. Furthermore, depending on the patients’ age, the time elapsed between the onset of clinical manifestations and hospital evaluation, and the clinical form, acute Q fever displays significant differences.