Duration of Sapovirus RNA Excretion in Infected Food Handlers and Genetic Analysis of Detected Virus

Abstract

Sapovirus (SaV) is an important pathogen causing gastroenteritis in humans. Studies of SaV outbreak associated with food-handlers who were infected with SaV have been frequently reported. However, the precise reports about the duration of SaV shedding from food-handlers are not found in SaV food-borne outbreak. In this report, we examined quantitative analysis of the viral loads in 36 stool specimens from 10 food-handlers (5 symptomatic food-handlers and 5 asymptomatic food-handlers), and genetic analysis of the detected viruses were performed. Our results showed that SaV excretion decreased to an undetectable level on 44 days; however, some individuals excrete SaV in feces at high concentrations until 33rd days after outbreak. In addition, we identified the amino acid substitutions caused by the point mutation at the capsid region on 21st days. We should carefully monitor the food-handlers excreting SaV to prevent the spread of food poisoning associated with SaV.