Susceptibility of human rotavirus to ozone, high pressure, and pulsed electric field

The rotavirus causes a food-transmitted gastroenteritis that affects mainly children. Currently, the food industry is interested in alternative food-processing technologies, but research on the control of food-transmitted viruses by these technologies is limited. In this study, the human rotavirus was cultured on MA104 cells, and suspensions of the virus were prepared and treated with ozone, high pressure, and pulsed electric field (PEF). Virus viability was quantified as 50% tissue culture infectious doses (TCID50) per milliliter. Ozone at 25 microg/ml decreased rotavirus infectivity by 8 to 9 log10 TCID50/ml. High pressure was extremely effective against the rotavirus; treatment with 300 MPa for 2 min at 25 degrees C inactivated approximately 8 log10 TCID50/ml. A small fraction of the virus population, however, remained resistant to pressure treatments of up to 800 MPa for 10 min. Viruses surviving these extreme pressures showed a cytopathic effect different from that of the untreated viruses. The rotavirus was found to be resistant to PEF treatment at 20 to 29 kV/cm, for which no appreciable reductions in virus titer were observed.