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Short answer The 48-hour rule Why hand sanitizer is not enough How do I protect my roommate? Staying hydrated is the real treatment What about exams and sports? When should I go to urgent care or the ER? Common questions from students Common questions Related questions SourcesStay away from class, the dining hall and shared bathrooms until at least 48 hours after your last vomiting or diarrhea.
Norovirus can still be in your stool for days to weeks after you feel better, so hand washing with soap matters more than anything else.
The 48-hour rule
The CDC recommends staying home from work, school and food handling for at least 48 hours after symptoms stop. You may feel fine sooner. Norovirus is the main cause of the college stomach bug and spreads in dorms and dining halls because very few virus particles can make someone sick.
Why hand sanitizer is not enough
Alcohol hand sanitizer does not reliably kill norovirus. Wash your hands with soap and water for at least 20 seconds after the bathroom and before touching food. Clean surfaces with a bleach-based cleaner or one made to kill norovirus.
How do I protect my roommate?
- Use your own bathroom if you can, or clean the toilet and handles after each use
- Wash soiled clothes and sheets on hot, then dry on high
- Do not make food for others for at least 2 days after recovering
- Wear gloves when cleaning up vomit, and wash hands afterward
Staying hydrated is the real treatment
Most cases clear in 1 to 3 days. Dehydration is the main risk. Sip water or an oral rehydration drink, eat bland foods when you can, and rest. Signs of dehydration include dark urine, dizziness, a very dry mouth and not peeing for 8 hours or more.
What about exams and sports?
- Ask for a makeup exam if you are still weak, and bring a note
- Athletes can return when they are eating and drinking normally and are past the 48-hour mark, with their trainer's okay
- Skip a shift that involves preparing or serving food until 48 hours or more
When should I go to urgent care or the ER?
Go to urgent care or the ER for signs of severe dehydration, blood in vomit or stool, a fever over 102 F, or vomiting that does not stop for more than a day. Call 911 for fainting, confusion or severe belly pain.
If you are not sure what you have, our AI doctor asks a few questions and sends you a care note you can bring to student health.
Common questions from students
How long is norovirus contagious? From when symptoms start until at least 2 days after they stop, and sometimes longer.
Is it norovirus or food poisoning? They look alike. A cluster of people sick around the same time points to norovirus. See how long a stomach bug lasts.
Can I go to class if I only vomited once? If you were sick, wait the 48 hours after your last symptom.
Does the stomach flu mean I have the flu? No. Stomach flu is a common name for a stomach virus like norovirus, not influenza.
How long until I can eat normally? Start with bland food and add more as your stomach settles, often within a day or two.
Common questions
When can I go back to class after a stomach bug?
Stay away from class, the dining hall and shared bathrooms until at least 48 hours after your last vomiting or diarrhea. Norovirus can still be in your stool for days to weeks after you feel better, so hand washing with soap matters more than anything else.
How long is norovirus contagious?
From when symptoms start until at least 2 days after they stop, and sometimes longer.
Is it norovirus or food poisoning?
They look alike. A cluster of people sick around the same time points to norovirus. See how long a stomach bug lasts.
Can I go to class if I only vomited once?
If you were sick, wait the 48 hours after your last symptom.
Does the stomach flu mean I have the flu?
No. Stomach flu is a common name for a stomach virus like norovirus, not influenza.
How long until I can eat normally?
Start with bland food and add more as your stomach settles, often within a day or two.