Basics
Is norovirus the same as stomach flu?
90-Second Answer
Last updated June 28, 2026
Short answer
No. Norovirus is often called stomach flu, but it is not the flu virus.
What it means
The flu is caused by influenza viruses and usually affects the respiratory system. Norovirus causes gastroenteritis, which affects the stomach and intestines.
What to know
The nickname can be confusing. If a report says norovirus, it is talking about a stomach and intestinal illness, not seasonal influenza.
When to check official guidance
Use CDC norovirus pages for norovirus questions and CDC influenza pages for flu-specific guidance.
Sources
Hantavirus Now summarizes external public health information in plain language. Source links open in a new tab.