Overlooked risk factors for European autochthonous strongyloidiasis, Paris, France.

Abstract

Objectives: In non-endemic settings, Strongyloides stercoralis infection is primarily suspected in individuals with a history of travel to tropical regions. However, autochthonous transmission in Europe remains underrecognized. We aimed to identify epidemiological and clinical risk factors for strongyloidiasis in a temperate setting.

Methods: We conducted a retrospective multicenter study in six Parisian university hospitals including patients diagnosed with confirmed strongyloidiasis between 2014 and 2019. Epidemiological, clinical, and biological characteristics were analyzed to identify populations at risk.

Results: Among 74 patients included, 65 (87.8%) had infections associated with travel to highly endemic tropical regions, whereas 9 (12.2%) were classified as European cases, including five men who have sex with men (MSM) living in Mainland France and four individuals originating from South-Eastern Europe. While infections among travelers returning from highly endemic regions were predominantly asymptomatic, European cases were more frequently symptomatic and included two cases of hyperinfection syndrome, one of which was fatal.

Conclusion: Although imported infections remain predominant presentation of strongyloidiasis in Mainland France, MSM and individuals originating from South-Eastern Europe appear to represent overlooked populations at risk. Screening strategies should therefore be extended to these groups, particularly before immunosuppressive therapy or in the presence of eosinophilia or compatible clinical manifestations.