Introduction: Alveolar echinococcosis (AE) is a rare zoonotic infection caused by Echinococcus multilocularis. In recent years, the number of reported cases has increased across Europe, including Switzerland. Methods: We conducted a retrospective observational study at Lausanne University Hospital (CHUV), including all AE cases diagnosed between 2010 and 2023 within the Departments of Gastroenterology and Hepatology, Visceral Surgery, and Infectious Diseases. Results: Eighty patients with AE were identified. Half of them were male. The mean annual incidence was 0.53 cases per 100,000 population (range, 0.14–0.85), with a statistically significant increase over time in the canton of Vaud (p = 0.037). The median age at diagnosis was 61.5 years, showing a significant downward trend during the study period. At diagnosis, 45 patients (56.3%) were asymptomatic, and 17 (21.3%) were immunosuppressed. Compared with immunocompetent patients, immunosuppressed individuals more often presented asymptomatically, had significantly smaller hepatic lesions, and were more frequently seronegative. Conclusions: This study demonstrates evolving epidemiological patterns of AE in Switzerland, characterized by increasing incidence and a high proportion of asymptomatic cases. Immunosuppressed patients tended to present with milder disease. Our findings highlight the need for strengthened surveillance and support the ongoing efforts to establish a national AE registry.
Weikert et al. (2026) studied this question.