Hi trees ! It is very nice he is active at 90. Take care of him. Yes! norovirus can cause that symptoms.Now what to do ! Take domperidone in morning before vomit feeling. Need to talk to physician. If saliva in pink colour. Need to check heart. Well over all at this life stage keep monitoring heart, diabetes, anemia and full abdomen ultrasound for rest of organ. need check up every 6 month. Take care bye.

Hello!

Thank you for the query.

There can be plenty of reasons for vomiting in the morning. The most common are due to stomach diseases like peptic ulcer, stomach mucosa inflammation, stomach cancer, gallstones, bowel obstruction, vertigo (caused by brain diseases or internal ear diseases), diabetes and many more.
If your dad is having also abdominal pain it can be peptic ulcer (the pain is in the upper middle abdomen) or gallstones (pain in the right upper abdomen radiating to the back). If he has also lost some weight recently cancer is possible. If he has any dizziness or headaches, brain problems are possible.
Depending of the additional symptoms, proper diagnostics is advisable(upper GI endoscopy, abdominal ultrasound, full blood work, liver tests, pancreas tests, colonoscopy, head CT, blood sugar level, etc).

Hope this will help.
Regards.