Brief Answer:
Not normal

Detailed Answer:
Hello

Thanks for the query

Norovirus induced diarrhea usually should subside within a week. The fact that it is lasting for more than a week calls for further investigation to rule out amebic or bacterial origin of diarrhea. I emperically start a combination drug of ciproflox with tinidazole twice a day for 5 days along with that I prescribe a probiotic like tab vsl-3 once a day for 7 days to replenish the gut with good bacteria
My further suggestions are

1. drink plenty of water. Upto 3 liters per day to stay well hydrated. The best way is to buy an ors XXXXXXX mix it in a liter of water and drink in sip by sip
2. avoid milk and milk products
4. avoid food rich in fat

If symptoms do not improve then please approach a doctor for a stool exam and colonoscopy

I hope I was of help, if you have any further queries please get back to me

Regards

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