Hi
For preventing food poisoning or acute gastroenteritis, food hygiene is important: choice of food source, washing well, hygienic handling as well as hygienic cooking/preparation area, hand hygiene before eating & after using washroom, all play important role.
Next Steps
if recurrent issue of vomiting & diarrhoea, please consult ur local Pediatrician & consider stool culture as well as urine routine.