Assessment of drivers of antimicrobial use and resistance in pig and poultry farming in the Msimbazi River Basin in Tanzania

Abstract

Abstract Background Uncontrolled use of antimicrobials both in humans and animals coupled with environmental contamination by effluents, toxic chemicals, and heavy metals exacerbate the development and spread of antimicrobial resistance. This paper assessed the drivers of antimicrobial use and resistance in poultry and domestic pig farming and the environment in a densely populated area, with wide-ranging human activities in Tanzania. Methods This was a cross-sectional study conducted from June to September 2019 in the Msimbazi River basin in Eastern Tanzania, which covers an area of 271km2 and harbours a population of approximately 1.2 million. Questionnaires, in-depth interviews, and focus group discussions (FGDs) were used to collect information regarding demographic characteristics, knowledge, practices, attitudes, and perceptions of the drivers of antimicrobial use and resistance in animal farming and the environment. Descriptive statistics and the chi-square tests were used to analyse data from the survey and p<0.05 was considered as statistically significant. The FGDs and interviews were transcribed, coded into categories, and analysed manually. Results We found a higher proportion of usage of veterinary antimicrobials for prophylactic purposes (87.6%), especially tetracycline and quinolones in poultry and pigs farming, than for therapeutic purposes (80.5%). The farming experience was significantly (p<0.05) related to the knowledge on the source of antimicrobial use, methods used in disease diagnosis, access to veterinary services, stocking of antimicrobial at home, and presence of agriculture activities that involve use of manure. Additionally, a significant relationship (p<0.05) existed between the level of education and the practicing group treatment, inadequate extension officers, and inadequate knowledge on infection prevention and control of animal diseases. Uncontrolled disposal of wastes from households, uncontrolled disposal of human and veterinary drugs, and weak implementation of the legal framework was identified as the major pollutants of the environment. Conclusion The high usage of veterinary antimicrobials and environmental contamination taking place in the Msimbazi Basin requires agent multisectoral interventions, including implementation of long-term sustainable training programs aiming at reducing farmers' reliance on antimicrobials, as well as a review of government strategies, policies, and regulations on AMU.