how long is incubation period for gastric flu
What is the incubation period of the stomach flu (norovirus and others)? Answer: The incubation period of the stomach flu is usually about 48 hours but it can vary. It generally takes about 48 hours from the time you swallow the virus (norovirus or others) to the time when you start to feel sick1.However, it can easily be less time or more time.nswer: The incubation period of the stomach flu is usually about 48 hours but it can vary. My sister has 5 children. They caught the stomach flu from relative they saw on Christmas day (Friday, December 25, 2009). My sister's first child got sick on Sunday night, 2 others on Monday night, and a 4th on Tuesday.