Surveillance of tuberculosis in Switzerland and the Principality of Liechtenstein, 2009 to 2019.

Abstract

To describe the epidemiology of tuberculosis in Switzerland from 2009 to 2019.METHODS: Analysis of Swiss notification data. Tuberculosis cases declined from 553 (7.1/100,000) in 2009 to 437 (5.1/100,000) in 2019. The male-to-female ratio was 3:2. Although the number of tuberculosis cases of Swiss origin has steadily declined, the number of tuberculosis cases of foreign origin was rather stable but peaked in 2016. Overall, three quarters of tuberculosis cases were among people of foreign origin; of these, around half were from East Africa, Southern East Europe, and Southern Asia. Forty-nine percent had extrapulmonary manifestations. Every year, with little variation, 7-16 cases with rifampicin resistance were reported (2.9% overall). Independent risk factors for rifampicin resistance were prior anti-tuberculosis treatment, with an adjusted odds ratio (aOR) of 5.5 and a 95% confidence interval (CI) from 3.7 to 8.1, and foreign origin (aOR 3.6, 95% CI 2.0-7.0), particularly Georgia (aOR 10.0, 95% CI 4.0-23.1), Ethiopia (aOR 9.4, 95% CI 3.5-24.2), Tibet (aOR 6.9; 95% CI 2.9-16.6) and Somalia (aOR 8.1, 95% CI 4.0-17.2), together with Eritrea (aOR 2.6, 95% CI 1.1-5.9), accounting for more than half of all 134 cases . From 2016 to 2018, applying the World Health Organization definitions, overall treatment success in culture-confirmed pulmonary cases was 78%, and thus below the target of 85%. Since most cases with unsuccessful outcome are due to missing information, the proportion of unsuccessful outcome are overestimated. Autochthonous tuberculosis has become rare in Switzerland and the new diagnoses are increasingly attributable to immigration. Rifampicin resistance remains rare. Switzerland currently fails to achieve international targets for treatment success.