Hi good morning..Welcome to HCM. I am Dr Jigar ( Infectious disease specialist). Your concern is justifiable but you need to know following things regarding norovirus infection which will be your answer. 1) Norovirus is very contagious and affect all age group. It is very easily spread by infected person( their contaminated hands and articles touched by them) especially when they are in initial period of infection ( 12 to 48 hrs) where they don t have much discomfort. 2) Most of the time virus shedding stops when person recovers from illness but it may continue. 3) My advice to you is if you really wanna go for sail just ensure that before eating or drinking anything wash your hands thoroughly. 4) Also take medicines for symptomatic relief of diarrhea and fever. 5) Don t share objects with other people. And remember that illness is self limiting and if hydration is maintained during illness, it posses no threats. Wish you a great journey. Regards. Dr jigar.