Animal husbandry and environmental conditions are associated with cefotaxime-resistant Escherichia coli in yard soil in peri-urban Malawi

Abstract Soil is an important reservoir for antimicrobial resistance (AMR) and increasingly recognized as a pathogen transmission pathway. While studies have detected AMR in soil in various settings, dominant contributors to domestic soil contamination with antimicrobial-resistant organisms in low-income countries remain unidentified. We conducted a cross-sectional study with 237 households in southern Malawi, specifically peri-urban Bangwe near Blantyre, to identify factors associated with the abundance of cefotaxime - resistant E. coli in yard soil. Enumerators employed structured surveys and sampled 30 cm 2 of yard soil per household. We used IDEXX Quanti-Tray/2000 with Colilert-18 and cefotaxime supplement to enumerate the most probable number (MPN) of cefotaxime-resistant E. coli per dry gram of soil. We conducted multivariable regression to assess associations between the abundance of cefotaxime-resistant E. coli and household sanitation, animal ownership and management, child health and antibiotic use, and weather. Of 228 soil samples, 68% harbored cefotaxime-resistant E. coli at a mean of 0.90 log 10 -MPN/dry gram. Compared to households without animals, households had approximately 0.50-log lower mean cefotaxime-resistant E. coli abundance in soil if animals were enclosed at night and 0.50-log higher abundance if they were not (p-values