Market-source pathogens in traditional food markets, 2000-25: a systematic review and meta-analysis

Traditional food markets, often referred to as wet markets, live poultry markets, or farmers' markets, remain a major source of animal-origin foods and fresh produce in many low-income and middle-income countries (LMICs). These markets bring humans, domestic animals, wildlife, and the environment into close contact and have been repeatedly implicated in the emergence of zoonotic and foodborne diseases. Yet, the overall global burden, pathogen spectrum, and risk gradients within these settings have not been comprehensively quantified.

We conducted a systematic review and meta-analysis of studies published between Jan 1, 2000, and Oct 31, 2025, following the PRISMA 2020 reporting guidelines. We searched major English and Chinese databases for cross-sectional or baseline studies reporting the detection of zoonotic or foodborne pathogens in traditional food markets or related retail settings. Studies were excluded if they were not conducted in traditional markets, had non-extractable data, had a sample size of fewer than 20, had intervention-related outcomes, had duplicate populations, or did not have prevalence or detection rate reporting. Data were extracted as detection records, defined as unique pathogen-sample type-market setting combinations. Study quality was assessed with the Joanna Briggs Institute tool for prevalence studies. We used random-effects meta-analysis of logit-transformed proportions to estimate pooled prevalence and 95% CIs overall and across major subgroups. Heterogeneity was assessed with I² and τ², and meta-regression was used to examine temporal trends and associations between study quality and prevalence. Robustness was assessed with leave-one-out analyses and small-study effects. This study is registered with PROSPERO, CRD420251267834.

We included 247 studies comprising 597 detection records from 41 countries across 16 regions. The global pooled prevalence of market-source pathogens in traditional markets was 15·32% (95% CI 13·96-16·80). By pathogen kingdom, pooled prevalence was 19·41% (16·21-23·08) for bacteria, 8·40% (7·15-9·83) for viruses, and 27·05% (21·91-32·89) for parasites. Regionally, prevalence was highest in southeast Asia (23·09% [18·43-28·52]), followed by south Asia (15·52% [10·06-23·20]) and east sub-Saharan Africa (14·54% [7·13-27·40]). By market type, fish and seafood markets showed the highest pooled prevalence (37·87% [26·05-51·33]), and by sample type, the highest estimates were observed in fish and seafood, raw meat, and environmental samples. Lower estimates were observed in cooked foods, fruit and vegetables, and worker samples, suggesting a gradient from animal and environmental reservoirs towards ready-to-eat foods and humans. Meta-regression showed no significant global linear temporal trend in prevalence, whereas higher methodological quality was associated with lower reported prevalence. Leave-one-out analyses suggested that no single study substantially altered the overall findings.

Traditional markets represent persistent global hotspots for zoonotic and foodborne pathogens, particularly in LMICs and high-risk food chains. The observed exposure gradient highlights crucial intervention points. These findings support a One Health-oriented framework for risk assessment and targeted surveillance, while emphasising the need for harmonised, prospective, multipathogen studies.

Foundation of Key Laboratory of Veterinary Biotechnology, National Key Research and Development Program of China, and the International Joint Laboratory on Tropical Diseases Control in Greater Mekong Subregion.