Kuenzli, EstherEstherKuenzliJaeger, Veronika KVeronika KJaegerFrei, RenoRenoFreiNeumayr, AndreasAndreasNeumayrDeCrom, SusanSusanDeCromHaller, SabineSabineHallerBlum, JohannesJohannesBlumWidmer, Andreas FAndreas FWidmerFurrer, HansjakobHansjakobFurrer0000-0002-1375-3146Battegay, ManuelManuelBattegayEndimiani, AndreaAndreaEndimiani0000-0003-3186-5421Hatz, ChristophChristophHatz2024-10-232024-10-232014https://boris-portal.unibe.ch/handle/20.500.12422/126926BACKGROUND International travel contributes to the worldwide spread of multidrug resistant Gram-negative bacteria. Rates of travel-related faecal colonization with extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae vary for different destinations. Especially travellers returning from the Indian subcontinent show high colonization rates. So far, nothing is known about region-specific risk factors for becoming colonized. METHODS An observational prospective multicentre cohort study investigated travellers to South Asia. Before and after travelling, rectal swabs were screened for third-generation cephalosporin- and carbapenem-resistant Enterobacteriaceae. Participants completed questionnaires to identify risk factors for becoming colonized. Covariates were assessed univariately, followed by a multivariate regression. RESULTS Hundred and seventy persons were enrolled, the largest data set on travellers to the Indian subcontinent so far. The acquired colonization rate with ESBL-producing Escherichia coli overall was 69.4% (95% CI 62.1-75.9%), being highest in travellers returning from India (86.8%; 95% CI 78.5-95.0%) and lowest in travellers returning from Sri Lanka (34.7%; 95% CI 22.9-48.7%). Associated risk factors were travel destination, length of stay, visiting friends and relatives, and eating ice cream and pastry. CONCLUSIONS High colonization rates with ESBL-producing Enterobacteriaceae were found in travellers returning from South Asia. Though risk factors were identified, a more common source, i.e. environmental, appears to better explain the high colonization rates.en500 - Science::570 - Life sciences; biology600 - Technology::610 - Medicine & healtharticle10.7892/boris.593472527073210.1186/1471-2334-14-528