Acquisition of multidrug-resistant bacteria and colistin resistance genes in French medical students on internships abroad.

BACKGROUND: Acquisition of multidrug resistant bacteria (MDR) and colistin resistance genes by international travellers has been demonstrated. Studies conducted in medical students during internships abroad are scant. METHODS: Nasopharyngeal, rectal, and vaginal swabs samples were collected from 382 French medical students before and after travel to investigate the acquisition of MDR bacteria. The bacterial diversity in the samples was assessed by culture on selective media. We also genetically characterised the isolates of MDR bacteria including Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E), methicillin-resistant Staphylococcus aureus (MRSA), and Carbapenemase-producing Enterobacteriacae (CPE) using the real-time polymerase chain reaction method. The samples were collected from 293 students and were investigated for mcr colistin-resistance genes using RT-PCR directly on the samples, followed by conventional PCR and sequencing. RESULTS: A proportion of 29.3% (112/382) of the participants had acquired ESBL-E and 2.6% (10/382) had acquired CPE. The most common species and ESBL-E encoding gene were Escherichia coli (125/127 isolates, 98.4%) and blaCTX-M-A (121/127, 95.3%), respectively. A proportion of 6.8% (20/293) of the participants had acquired mcr-1 genes, followed by mcr-3 (1/293, 0.3%) and mcr-8 (1/293, 0.3%). We found that taking part in humanitarian missions to orphanages (aRR = 2.01, p < 0.0001), being in contact with children during travel (aRR = 1.78, p = 0.006), the primary destination of travel being Vietnam (aRR = 2.15, p < 0.0001) and north India (aRR = 2.41, p = 0.001), using antibiotics during travel (aRR = 1.77, p = 0.01), and studying in 2018 (aRR = 1.55, p = 0.03) were associated with the acquisition of ESBL-E. When the primary destination of travel was Vietnam (aRR = 2.74, p < 0.0001) and the year of study was 2018 (aRR = 1.93, p < 0.002), this was associated with acquisition of colistin resistance genes. CONCLUSION: Medical students are at a potential risk of acquiring ESBL-E, CPE and colistin resistance genes. A number of risk factors have been identified, which may be used to develop targeted preventive measures.

Infectious disease symptoms and microbial carriage among French medical students travelling abroad: A prospective study.

BACKGROUND: In France, no previous studies have focused specifically on health problems among medical students during internships abroad including the clinical symptoms suggestive of infectious diseases and the acquisition of pathogen carriage. METHODS: Clinical follow up and qPCR based respiratory, gastrointestinal and vaginal pathogen carriage before and after travel were prospectively assessed in a cohort of medical students departing from Marseille, France. RESULTS: 134 students were included. 73.9%, 38.8% and 5.0% of students reported gastrointestinal, respiratory and vaginal symptoms, respectively. The acquisition rate of Enteroaggregative Escherichia coli (EAEC) and Enteropathogenic E. coli (EPEC) was 53% and 41%, respectively. The acquisition of respiratory viruses was low but associated with persisting symptoms, while bacterial acquisition ranged from 3.3% for Streptococcus pyogenes to 15.0% for Haemophilus influenzae. Gardnerella vaginalis and Atopobium vaginae acquisition rates were 7.7% and 14.3% respectively. Five students (5.1%) had molecular quantification criteria for bacterial vaginosis on return. CONCLUSION: This preliminary study demonstrates that besides the known risk of gastrointestinal and respiratory infections and associated changes in intestinal and respiratory microbiota, medical students abroad may also experience changes in vaginal microbiota leading, in some cases, to clinical symptoms or the acquisition of bacterial vaginosis, which may be asymptomatic.