High-level Colonization With Antibiotic-Resistant Enterobacterales Among Individuals in a Semi-Urban Setting in South India: An Antibiotic Resistance in Communities and Hospitals (ARCH) Study

Background Antimicrobial resistance poses a significant threat to public health globally. We studied the prevalence of colonization with extended-spectrum cephalosporin-resistant Enterobacterales (ESCrE), carbapenem-resistant Enterobacterales (CRE), and colistin-resistant Enterobacterales (Col-RE) in hospitals and the surrounding community in South India.Methods Adults from 2 hospitals and the catchment community who consented to provide stool specimens were enrolled. Stools were plated on CHROMagar selective for ESCrE, CRE, and Col-RE. Bacterial identification and antibiotic susceptibility testing were done using Vitek 2 Compact and disc diffusion testing. Colistin broth microdilution was performed for a subset of isolates. Prevalence estimates were calculated with 95% confidence intervals (CIs), and differences were compared across populations using the Pearson ?(2) or Fisher exact test.Results Between November 2020 and March 2022, 757 adults in the community and 556 hospitalized adults were enrolled. ESCrE colonization prevalence was 71.5% (95% CI, 68.1%-74.6%) in the community and 81.8% (95% CI, 78.4%-84.8%) in the hospital, whereas CRE colonization prevalence was 15.1% (95% CI, 12.7%-17.8%) in the community and 22.7% (95% CI, 19.4%-26.3%) in the hospital. Col-RE colonization prevalence was estimated to be 1.1% (95% CI, .5%-2.1%) in the community and 0.5% (95% CI, .2%-1.6%) in the hospital. ESCrE and CRE colonization in hospital participants was significantly higher compared with community participants (P < .001 for both).Conclusions High levels of colonization with antibiotic-resistant Enterobacterales were found in both community and hospital settings. This study highlights the importance of surveillance of colonization in these settings for understanding the burden of antimicrobial resistance.