If you have vomiting and diarrhoea, you should carry on breastfeeding, but make sure you drink plenty of liquids to keep up your fluid levels and prevent dehydration. See your GP if your symptoms don't get better after a few days.
There are very few illnesses in mothers that mean you should stop breastfeeding. Most common illnesses, like colds and flu, can't be passed through breast milk. In fact, if you are unwell, your breast milk will contain antibodies, which help to protect your baby from getting the same illness.
Further information:
Your health, your choices