A systematic review on the relationship between international migration and antimicrobial resistance

Introduction: Antimicrobial drug resistance (AMR) is considered a serious threat to public health worldwide. The relation between AMR and human mobility, particularly international migration, has drawn attention from the scientific community in recent years. However, several aspects about this relation remain unclear. Therefore, we aimed at expanding and updating previous systematic review studies, with a novel focus on the AMR prevalence in migrants compared to the local population of the host country, to examine external validity of previous findings.Methods: We searched in Ovid MEDLINE all types of observational studies, without language or year of publication restrictions. We aimed at exploring differences in countries´ bacterial drug resistance rates based on immigration rates. All types of AMR were included, except for those related to HIV/AIDS and Tuberculosis. The comparator group of interest was the local population of the host country. The study protocol is registered with PROSPERO, number CRD42018114436. Results: After screening of 322 articles, 15 papers were selected for data extraction, including 1930 migrants. Compared to the local population, higher rates of methicillin-resistant Staphylococcus aureus, Panton-Valentine leucocidin positive strains, multidrug-resistant Gram-negative bacteria, vancomycin-resistant Enterococcus, and having at least one multidrug-resistant organism were found in migrants in 12 of the 15 papers. Rates of AMR did not differ significantly in two studies and only one of them reported a lower burden of AMR in migrants.Conclusions: Higher prevalence of AMR in migrants were presented in the majority of the included articles, addressing the emerge of the circulation of resistant strains within this group. More detailed descriptions, including time span and route taken by migrants to arrive to country of destination and length of stay by the time of inclusion are essential to gain a deeper understanding of the relation in between AMR and migration. Countries with high migration rates outside Europe should be encouraged to implement strategies for screening of both local population and migrants in countries.