Human exposure to antimicrobial resistance from poultry production: assessing hygiene and waste-disposal practices in Bangladesh

The unregulated use of antibiotics is linked with intensive poultry farming in developing economies. In low-and middle-income countries, the dissemination of antimicrobial resistance (AMR) has also been attributed to contamination, poor public health infrastructure and inadequate waste disposal practices. There are limited data on hygiene and waste disposal practices in small-scale commercial and household poultry farming and market sales in Bangladesh. Our objective was to explore human exposures, hygiene and waste disposal practices in poultry raising and processing to identify probable pathways for transmission of AMR bacteria. We employed mixed methods approaches of in-depth interviews and structured observations to assess exposures, hygiene behaviours and waste-disposal practices relating to poultry production in Bangladesh. Interviews (n=18) were conducted with commercial poultry farmers, backyard poultry owners, and live poultry market workers. Structured observations were conducted for six-hours in five households, five commercial farms and five urban live bird markets to assess the frequency of transmission/ exposure events in these settings. Interviews highlighted existing practices that can contribute to transmission of antimicrobial resistant bacteria from poultry to humans. In households and farms, untreated poultry waste and carcasses were disposed of on agricultural fields and in water bodies which may contaminate surface water and soil with poultry faeces. Biosecurity precautions were not used, and hands were rarely washed with soap after handling poultry. In urban markets, live poultry slaughter and processing was done on site with bare hands which were subsequently rinsed in water stored in containers without soap. Solid waste from poultry processing was disposed into municipal waste disposal stations and liquid waste was discarded into open drains. Structured observations revealed that workers in live poultry markets had the highest direct contact with poultry and poultry waste, almost tenfold higher than those working in poultry farms or with domestic poultry (59 vs 544 observed direct poultry exposure events) placing them at particularly high risk of exposure to faecal bacteria. Biosecurity measures were limited; in some cases, workers in commercial farms and urban markets had gloves and masks but often did not use them. In 88% (606/689) of exposure events no handwashing took place. Eating and drinking after handling poultry and without washing hands was observed in all three settings. These data suggest effective intervention strategies to reduce environmental contamination and to decrease risks of transmission should be prioritized. Data on prevalence of risk behaviours and AMR transmission to humans along environmental pathways can inform policy and intervention strategies.