Prevalence of Rotavirus and Porcine Enteric Calicivirus at Various Stages of Pork Carcass Processing

Introduction: Porcine enteric calicivirus (PEC) and rotavirus (RV) infections are common in swine and raises concerns about the potential for zoonotic transmission through undercooked meat products. Enteric viruses can potentially contaminate carcasses during meat processing operations. There is a lack of information on the prevalence and control of enteric viruses in the pork processing chain.

Purpose: The study compared the incidence and levels of contamination of hog carcasses with F- coliphages (FC), RV and PEC at different stages of the dressing process.

Methods:  One hundred swab samples (100 cm²) were collected from random sites on hog carcasses at 4 different stages of the dressing process and from meat cuts on 10 separate occasions over the span of a year from 2 pork processing plants (1,000 samples in total, 500/plant). Numbers of viable FC were determined by plaque assay and the numbers of genome copies (GC) of RV and PEC were determined by qRT-PCR.

Results:  FC, RV, and PEC were detected in 100%, 100%, and 18% of samples, respectively, after bleeding for plant 1 and in 100%, 98%, and 36% of samples, respectively, after bleeding for plant 2. After evisceration, FC, RV, and PEC were detected in 63%, 21% and 3% of samples, respectively, for plant 1 and in 25%, 1%, and 0% of samples, respectively for plant 2. FC, RV, and PEC were detected on 21%, 1%, and 5% of pork cuts, respectively, for plant 1 and on 13%, 0%, and 0% of pork cuts, respectively, for plant 2.

Significance:  The prevalence of PEC and RV on pork is progressively reduced along the pork processing chain but the viruses are not completely eliminated. The simultaneous detection of viable FC suggests that consumers could be at risk when consuming undercooked meat contaminated with pathogenic enteric viruses.