Dirt floors and domestic animals are associated with soilborne exposure to antimicrobial resistant E. coli in rural Bangladeshi households

Abstract

Soil can harbor enteropathogens and antimicrobial-resistant organisms in settings with domestic animals. We enrolled 49 households with young children (28 soil floors, 21 concrete floors) in Bangladesh and recorded animal ownership/management. Staff swabbed the floor of childrens sleeping area with a sterile sponge and collected floor dust and a child hand rinse. We used IDEXX QuantiTray/2000 with and without cefotaxime supplementation to enumerate cefotaxime-resistant and generic E. coli. There was 8.0 g/m2 of dust on soil floors vs. 0.2 g/m2 on concrete floors (p-value=0.005). We detected E. coli on 100% of soil vs. 86% of concrete floors and cefotaxime-resistant E. coli on 89% of soil vs. 43% of concrete floors (p-values<0.05). Cefotaxime-resistant E. coli prevalence on floors was 36% in compounds without animals, 79% in compounds with animals and 100% if animals stayed indoors overnight or the floor had animal feces; associations were strongest for chickens. In multivariable models, generic and cefotaxime-resistant E. coli counts were 1.5-2 log higher on soil vs. concrete floors, and counts on floors and child hands were 0.17-0.24 log higher for every 10 additional chickens owned (p-values<0.05). Efforts to mitigate infections and antimicrobial resistance in low-income countries should test flooring improvements and hygienic animal management. SynopsisIn rural Bangladeshi households, generic and cefotaxime-resistant E. coli were more common on soil floors than concrete floors and among households with higher cohabitation intensity with domestic animals, especially chickens.