Low rates of enteric pathogenic bacteria and resistance gene carriage in the sheltered homeless population in Marseille, France

Abstract

We aimed to assess the prevalence of pathogenic bacteria and resistance genes in rectal samples collected among homeless persons in Marseille, France. In February 2014 we enrolled 114 sheltered homeless adults who completed questionnaires and had rectal samples collected. Eight types of enteric bacteria and 15 antibiotic resistance genes (ARGs) were sought by real-time polymerase chain reaction (qPCR) performed directly on rectal samples. ARG-positive samples were further tested by conventional PCR and sequencing. We evidenced a 17.5% prevalence of gastrointestinal symptoms, a 9.6% DNA-prevalence of enteric bacteria carriage, including Escherichia coli pathotypes (8.7%) and Tropheryma whipplei (0.9%). Only 2 persons carried blaCTX-M-15 resistance genes (1.8%), while other genes, including carbapenemase-encoding genes and colistin-resistance genes, (mcr-1 to mcr-6, mcr-8) were not detected. Our results suggest that sheltered homeless persons in Marseille do not have a high risk of harbouring gastrointestinal antibiotic resistant bacteria. Keywords: antibiotic resistance gene; enteric bacteria; homeless; real-time polymerase chain reaction (qPCR)

Epidemiological Investigations of Infectious Diseases among Mobile Populations at the University Hospital Institute Mediterranean Infection in Marseille, France

“…We also evidenced the presence of digestive pathogen carriage in rectal, stool or saliva samples, such as E. coli pathotypes [ 17 ] and Tropheryma whipplei [ 33 ].…”

“…Recently, for screening of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), a nasal swab was self-collected by each homeless person using a standardized procedure that was previously explained to the participants by the investigators [ 15 , 16 ]. For gastrointestinal pathogen carriage, rectal [ 17 ] or stool samples were systematically collected on transport media [ 18 ]. Molecular prevalence surveys of the Antibiotic-resistance encoding Genes (ARGs) were performed on respiratory or rectal samples and compared to that of a control group (defined as the non-homeless group), including administrative staff, physicians, nurses, medical students and PhD students from our institute [ 19 ].…”