The autonomic nervous system (ANS) regulates the functions of our internal organs (the viscera) such as the heart, stomach and intestines.
The flu is contagious a day before and five days to a week after its onset. Young children, people over 65, those with compromised immune systems, and people with a terminal illness are at risk of death from the flu.
How long am I contagious if I have the stomach flu? You can be contagious from a few days up to two weeks or more, depending on which virus is causing your stomach flu (gastroenteritis). Although you typically feel better after a day or two, you're contagious for up to three days after you've recovered. 2  Some people may be contagious for up to two weeks after recovery. 3  Rotavirus.