I think stomach “flu” is a name that is given to about everything that upsets the stomach.
There is a lot of food poisoning around and it’s not only the cases that have to get to hospital.
If you eat something at 18:00 and wake up sick the next morning, feel miserable during the day and feel (a lot) better the day after that: Most likely food poisoning.
"Our lives begin to end the day we become silent about things that matter." - Martin Luther King, Jr.
It shouldn’t be “take care of yourself’, but “take care of each other” - 1vegan