Low prevalence of resistance genes in sheltered homeless population in Marseille, France, 2014–2018

• Main Authors: Ly TDA, Hadjadj L, Hoang VT, Louni M, Dao TL, Badiaga S, Tissot-Dupont H, Raoult D, Rolain JM, Gautret P
• Format: Article
• Language: English
• Published: Dove Medical Press 2019-05-01
• Series: Infection and Drug Resistance
• Subjects: antibiotic resistance gene; homeless; real-time polymerase chain reaction (qPCR); potential risk factors.
• Online Access: https://www.dovepress.com/low-prevalence-of-resistance-genes-in-sheltered-homeless-population-in-peer-reviewed-article-IDR

Tran Duc Anh Ly,1,2 Linda Hadjadj,2,3 Van Thuan Hoang,1–2,4 Meriem Louni,1,2 Thi Loi Dao,1–2,5 Sekene Badiaga,2,6 Herve Tissot-Dupont,2,3 Didier Raoult,2,3 Jean-Marc Rolain,2,3 Philippe Gautret1,21IRD, AP-HM, SSA, VITROME, Aix Marseille Univ., Marseille, France; 2IHU-Méditerranée Infection, Marseille, France; 3MEPHI, Aix Marseille Univ., Marseille, France; 4Family Medicine Department, Thai Binh University of Medicine and Pharmacy, Thành Phố Thái Bình, Vietnam; 5Pneumology Department, Thai Binh University of Medicine and Pharmacy, Thành Phố Thái Bình, Vietnam; 6Emergency Department, North Hospital, AP-HM, Marseille, FranceObjectives: The present study has explored the prevalence and potential factors contributing to the presence of nasal/pharyngeal resistant genes in homeless people.Methods: During the winters 2014–2018, we enrolled sheltered homeless adults and controls and collected nasal/pharyngeal samples. Sixteen antibiotic resistance genes (ARGs), including genes encoding for beta-lactamases and colistin-resistance genes, were searched by real-time polymerase chain reaction (qPCR) performed directly on respiratory samples and followed by conventional PCR and sequencing.Results: Over a 5-year period, using qPCR, we identified in homeless group (n=715) the presence of blaTEM (396/710, 54.7%), blaSHV (27/708, 3.6%), blaOXA-23 (1/708, 0.1%), while other genes including colistin-resistance genes (mcr-1 to mcr-5) were absent. We found a significantly higher proportion of ARG carriage among controls (74.1%) compared to homeless population (57.1%), p=0.038. Tobacco smoking (OR=4.72, p<0.0001) and respiratory clinical signs (OR=4.03, p=0.002) were most prevalent in homeless people, while vaccination against influenza (OR=0.31, p=0.016) was lower compared to controls. Among homeless people, type of housing (shelter A versus B, OR=1.59, p=0.006) and smoking tobacco (smoker versus non-smoker, OR=0.55, p=0.001) were independent factors associated with ARG carriage. By sequencing, we obtained a high diversity of blaTEM and blaSHV in both populations.Conclusion: The lower risk for ARGs in the homeless population could be explained by limited access to health care and subsequently reduced exposure to antibiotics.Keywords: antibiotic resistance gene, homeless, real-time polymerase chain reaction (qPCR), potential risk factors