Travel-associated carbapenemase-producing Enterobacterales: Epidemiology and risk factors in a Finnish cohort

Carbapenemase-producing Enterobacterales (CPE) are increasing worldwide, with strains associated with difficult-to-treat infections. We previously reported that international travel is a major source of CPE acquisition in the Helsinki region, Finland. To clarify the extent of importation, we investigated the epidemiology and associated risk factors of foreign-acquired CPEs.

We revisited two earlier cohorts. Cohort A (n = 187 after a one-year extension) comprised patients from 2010 through 2024 presumed to have acquired CPE abroad; CPE types were categorized by travel region. Cohort B included 3029 patients screened for CPE from 2010 through 2019 within 12 months after hospitalization abroad. Multivariable analysis identified factors that predispose to colonization.

Among patients hospitalized abroad (Cohort B), CPE rates were particularly high for South Asia (14.6 %) and North Africa (13.7 %). Across the 24 individual countries with data, the highest CPE colonization risks were observed for Egypt (20.8 %) and India (16.4 %). In addition to destination, independent risk factors included antibiotic use, travel type, short interval between discharge from a foreign hospital and screening (within one week or one month) and male sex. For South/Southeast Asia and sub-Saharan Africa, over 70 % of CPE carriers (Cohort A) had metallo-β-lactamase-producing Enterobacterales, predominantly NDM, whereas OXA-48-like enzymes predominated in North Africa and the Middle East.

Hospitalization in high-prevalence countries and antibiotic use emerged as key risk factors for CPE acquisition. Regional variation was evident: OXA-48-like enzymes dominated among CPEs linked to the Middle East and North Africa, whereas NDM was prevalent elsewhere in Eurasia and Africa.