Prevalence of Salmonella spp. in Retail Chicken Meat: A Multistate Study from Mexico

Introduction: Salmonella is an important health problem around the world, and meat is considered a main source of contamination. Chicken meat has been linked to numerous Salmonella outbreaks in USA and Europe. Thus, it is fundamental for health authorities and consumers to know the prevalence of this pathogen in chicken meat from retail markets. Unfortunately, this information is limited or lacking in Mexico.

Purpose: The objective of the present study was to evaluate the prevalence of Salmonella spp. in retail chicken meat from public markets and supermarkets from different geographical regions of Mexico.

Methods: A total of 1,293 chicken necks from public markets and supermarkets were obtained from six Mexican states. The microbiological analysis was carried out following methodology described by the European Food Safety Authority. Briefly, 25 g of neck skin (obtained from 3 necks) were pooled and cultured in buffered peptone water, tetrathionate and Rappaport-Vassiliadis broth and Xylose-Lysine-Deoxycholate agar supplemented with novobiocin (0.001%). Confirmation of presumptive Salmonella colonies was performed by PCR targeting the 16s rRNA and invA genes. 

Results: The average prevalence of Salmonella spp. in Mexico was 5.8%. Prevalence in supermarkets was 7.9% and 4.2% in public markets (P > 0.05).

Significance: The present study provides the first multistate data describing the prevalence of Salmonella spp. in retail chicken meat. The prevalence observed in Mexico concurs with levels reported in USA and Europe. Thus, as in many other countries, chicken meat in Mexico should be considered an important health threat.