The Effect of Temperature and Relative Humidity on the Survival of Foodborne Viruses during Food Storage

Abstract

Millions of people suffer from foodborne diseases throughout the world every year, and the importance of food safety has grown in recent years, worldwide. The aim of this study was to investigate the survival of major foodborne viruses, such as hepatitis A virus (HAV) and human norovirus (HuNoV), during food storage. HAV and two surrogates of HuNoV [MS2 and murine norovirus (MNV)] were inoculated into either oysters or fresh peppers and their survival on these food matrices was measured under various temperature (4°C, 15°C, 25°C, and 40°C) and relative humidity (RH) (50% and 70%) conditions. Inoculated viruses were recovered from food samples and quantified by plaque assay at predetermined time points over 2 weeks (0, 1, 3, 7, 10, and 14 days). Virus survival was the influenced primarily by temperature. On peppers at 40°C and 50% RH, greater than 4- and 6-log reductions of MNV and HAV, respectively, occurred within 1 day. All three viruses survived better on oysters. In addition, HAV survived better at 70% RH than at 50%. The survival data of HAV, MS2, and MNV were fitted to three different mathematical models (liner, Weibull, and biphasic models). Among them, the biphasic model was optimum in terms of goodness-of-fit. The results of this study suggest that major foodborne viruses such as HAV and HuNoV can survive over prolonged periods of time with limited reduction in numbers. Because the persistence of foodborne virus was observed on contaminated foods, precautionary preventive measures should be performed.