Detection of Toxoplasma Gondii and Risk Factors in Retail Meat in Southern Mexico.

BACKGROUND

Toxoplasma gondii is a major foodborne parasite of global public health relevance; however, data regarding its circulation in retail meat from tropical regions of southern Mexico remain limited. This study provides updated molecular evidence on the presence of T. gondii in meats commonly sold for human consumption and evaluates retail-level and meat-specific risk factors within a One Health framework.

METHODS

Between February and July 2024, a total of 276 meat samples (pork, chicken, beef, lamb, and horse meat) were collected from butcher shops, local markets, and supermarkets in Veracruz, Mexico. DNA was extracted using Chelex-based protocols, and T. gondii detection was performed by PCR targeting the B1 gene, followed by sequencing and phylogenetic analysis. Prevalence estimates were calculated using Wilson’s score and Clopper–Pearson confidence intervals, while associations with potential risk factors were evaluated using Fisher’s exact test and Firth penalized logistic regression.

RESULTS

T. gondii DNA was detected in 30 samples (10.9%). Pork showed the highest positivity rate (28.0%), whereas chicken (3.1%), lamb (1.4%), and horse meat (25.0%) exhibited lower detection frequencies; no beef samples tested positive. Contamination was significantly associated with the retail environment, with butcher shops (adjusted OR = 22.50) and local markets (adjusted OR = 12.55) presenting markedly higher odds of detection compared with supermarkets. Phylogenetic analysis revealed low genetic diversity, with all local isolates clustering within a single monophyletic clade.

CONCLUSIONS

Pork, particularly when sold in butcher shops and local markets, represents the primary source of T. gondii exposure among retail meats in tropical southern Mexico. These findings underscore the need for improved biosecurity in small-scale production systems, enhanced hygiene practices in informal retail settings, and strengthened public education on safe meat handling and cooking. Future studies incorporating parasite viability assays and expanded sampling are warranted to refine consumer risk assessments.