Quantifying enteropathogen contamination along chicken value chains in Maputo, Mozambique: A multidisciplinary and mixed-methods approach to identifying high exposure settings

Small-scale poultry production is widespread and increasing in low- and middle-income countries.

Exposure to enteropathogens in poultry faeces increases the hazard of human infection and related sequela, and the burden of disease due to enteric infection in children under five years of age in particular is substantial.

However, the containment and management of poultry-associated faecal waste in informal settings in low- and middle-income countries is largely unregulated.

To improve the understanding of potential exposures to enteropathogens carried by chickens, a research study was undertaken using mixed methods to map and quantify microbial hazards along production value chains among broiler, layer and indigenous chickens in Maputo, Mozambique.

The study, published in Environmental Health Perspectives (Nov 2023), was carried out by scientists from Emory University Rollins School of Public Health, Universidade Eduardo Mondlane, University of Washington School of Public Health, University of Liverpool and the International Livestock Research Institute.

To map and describe the value chains, the research team conducted 77 interviews with key informants working in locations where chickens and related products are sold, raised and butchered.

To quantify microbial hazards, they collected 75 chicken carcasses and 136 faecal samples from chickens along the value chain and assayed them by qPCR for the chicken-associated bacterial enteropathogens Campylobacter jejuni/coli and Salmonella.

They identified critical hazard points along the chicken value chains and identified management and food hygiene practices that contribute to potential exposures to chicken-sourced enteropathogens.

Campylobacter jejuni/coli was detected in 76% of faecal samples and 84% of carcass rinses and Salmonella in 11% of faecal samples and 21% of carcass rinses.

Prevalence and level of contamination increased as chickens progressed along the value chain, from no contamination of broiler chicken faeces at the start of the value chain to 100% contamination of carcasses with C. jejuni/coli at informal markets.

Few hazard mitigation strategies were found in the informal sector.

The high prevalence and concentration of C. jejuni/coli and Salmonella contamination along chicken value chains suggests a high potential for exposure to these enteropathogens associated with chicken production and marketing processes in the informal sector in the study setting.

Interventions at critical control points, such as the carcass rinse step and storage of raw chicken meat, could mitigate risk, but regulation and enforcement pose challenges.

The mixed-methods approach used in this study can act as a model to understand animal value chains, sanitary risks and associated exposures in other settings.

Citation
Lamar, F., Mucache, H.N., Mondlane-Milisse, A., Jesser, K.J., Victor, C., Fafetine, J.M., Saíde, J.Â.O., Fèvre, E.M., Caruso, B.A., Freeman, M.C. and Levy, K. 2023. Quantifying enteropathogen contamination along chicken value chains in Maputo, Mozambique: A multidisciplinary and mixed-methods approach to identifying high exposure settings. Environmental Health Perspectives 131(11): 117007.

Photo credit: Farmer in Lhate village, Chokwe, Mozambique (ILRI/Stevie Mann)