Survival of porcine reproductive and respiratory syndrome virus in fresh pork

Porcine reproductive and respiratory syndrome virus (PRRSV) remains one of the most economically important diseases of pigs. Transmission of PRRS virus has been reported through many routes, with aerosol route being the most predominant. There may also be a potential risk of transmission through contami-nated pork, but this has never been investigated. The purpose of this study was to experimentally contaminate fresh pork with three different concentrations of PRRSV and to study virus survival at ambient (25 °C), refrigerated (4 °C), and frozen (-20 °C) temperatures. Concentrations of virus representing natural infectivity level and 'worst case scenario' were studied. The virus was detected in fresh pork at all three virus concentrations for up to 48 h at ambient temperature. At 4 °C, the virus survived for 6 days in pork inoculated with the higher virus concentration and for 3 days in pork inoculated at the lower concentration. At frozen temperature, PRRSV was detected for up to 60 days in pork inoculated at the higher concentration and for 7 days in pork inoculated at the lower concentration. These results suggest that fresh pork has the potential to be a vehicle for virus dissemination depending upon temperature and time of storage.