Food-borne outbreaks caused by virus have been associated with the consumption of fresh produce. However, it is difficult to track the source of contamination due to the lack of sensitive methods of detection. In this study, we evaluated the presence of norovirus (NoV), rotavirus (RV) and hepatitis A virus (HAV) in fresh produce from the northwestern part of Mexico by reverse transcription quantitative PCR (RT-qPCR). Fresh produce was sampled from field and packinghouse facilities during different stages of the packing process. Surfaces of equipment, as well as water used for disinfection were also sampled. A total of 46 samples were analyzed for the quantification of virus: HAV was found in 28.2% of the samples, NoV in 32.6% and RV in 13.0%. Eleven samples were positive with at least two different viruses. These results show a high prevalence of these viruses in fresh produce and highlight the need to establish further virological surveys for this kind of products.
Viruses are considered important causal agents of food-borne diseases. Many outbreaks implicate the consumption of fresh produce, mainly because fresh vegetables are usually consumed raw or with minimum processing. In spite of this, in many undeveloped countries, analyses for microbial quality imply testing for bacterial but not for viruses' contamination. For that reason, it is necessary to generate information on the risk of virus transmission in fresh produce. In that way, producers can be warned of the risk of virus contamination, and they could implement good manufacturing practices to improve sanitary conditions in fresh produce processing plants for consumer protection to diminish food-borne outbreaks. We evaluated the prevalence of enteric viruses in fresh produce, water and surfaces of equipment by reverse transcriptase quantitative PCR, a sensitive method not commonly used for sanitary monitoring of food products.