“…Norovirus is highly infectious with very low infective dose, such as 10 to 1000 viral particles, and it can be transmitted through several routes, such as contact with contaminants, consumption of contaminated food or water, person-to-person transmission via the fecal-oral route, and a particular form of airborne transmission [6,7,8]. Therefore, it has a strong power to trigger epidemic outbreaks in semi-closed and closed settings, such as hospital, nursing home, cafeteria, school, and cruise ship [9,10,11,12,13,14,15,16,17,18,19]. On cruise ships, there are the several suitable conditions for the norovirus outbreaks, such as common food and drinks and high population density.…”