At 6-8 weeks of age puppies should receive their first vaccination; this is temporary and needs to be followed up with another one at 12 weeks. After the 12 week vaccination you can then take your puppy out in public areas.
You can be contagious from a few days up to two weeks or more, depending on which virus is causing your stomach flu (gastroenteritis).
After approximately 1 to 2 days, depending on the virus, stomach flu symptoms can appear. This period between the stomach flu transmission and the start of symptoms is the stomach flu incubation period.. In some cases, the stomach flu incubation period can be as short as 4 hours.nce the diarrhea has ended, a person with rotavirus gastroenteritis is no longer contagious. In the case of a norovirus infection (including Norwalk virus), a person is not usually contagious during the stomach flu incubation period.