Occurrence, load and transport-associated risk factors of Salmonella spp. in chickens sold in informal live bird markets in Centre-Nord Region, Burkina Faso

Informal poultry trade is central to live-bird value chains in sub-Saharan Africa, but transport and handling practices may facilitate the spread of zoonotic pathogens such as Salmonella spp. This regional study assessed the occurrence, bacterial load, and transport-related risk factors of Salmonella spp. in indigenous village chickens (Gallus gallus domesticus) marketed through the Kaya live-bird market in the Centre-Nord Region of Burkina Faso. A cross-sectional survey was conducted among 49 poultry collectors. Four clinically healthy indigenous chickens (Gallus gallus domesticus) were selected from each collector's transported batch using a stratified random sampling procedure based on spatial position (front, middle, rear) yielding a total of 196 birds. Birds originated from smallholder households in surrounding villages and were selected for live sale. Cecal contents were analyzed for Salmonella spp. using ISO 6579:2012 protocols, bacterial loads were quantified by the Most Probable Number method, and isolates were confirmed by MALDI-TOF MS. Structured interviews documented collector characteristics, sourcing, transport, hygiene, and biosecurity. Logistic regression identified factors associated with Salmonella occurrence, while linear regression assessed predictors of bacterial load. Salmonella spp. was detected in 41.3% of chickens, with 59.2% of collectors having at least one positive bird. Transporting 21-50 birds and collectors having verified the vaccination status of birds when collecting chickens were associated with higher odds of detection. Higher bacterial loads were linked to temporary stops during collection or transport and reuse of dedicated work clothing without proper cleaning. This regional survey highlights the collector and live-bird market stage as a critical interface for Salmonella circulation in village poultry systems. Practical recommendation include reducing overcrowding during transport, improving confinement and hygiene practices, and strengthening biosecurity measures among poultry collectors.