Norovirus
Norovirus is a highly contagious stomach bug that causes sudden vomiting and diarrhea, and it spreads easily in close-contact settings like cruise ships and care homes.
Snapshot: 9/5/2026, 11:31:05 PM · 3 tracked locations · 170,908 active cases (dataset)
At a glance
Quick facts
- How it spreads
- Norovirus spreads through contaminated food or water, contact with an infected person, or touching contaminated surfaces and then the mouth.
- How serious
- About 0.0 of every 100 confirmed cases died
- Where it's active
- Highest current burden: United States (US) and Japan (JP).
- Vaccine / treatment
- Thorough handwashing with soap and water is more effective than alcohol-based sanitizer against norovirus.
Important
Virus Tracker provides aggregated outbreak monitoring for education and situational awareness. It is not medical advice, a diagnostic service, or a substitute for guidance from qualified health professionals or official public health agencies. Always consult licensed clinicians and authoritative sources for personal health decisions.
Overview
Norovirus is one of the leading causes of acute gastroenteritis worldwide, notorious for causing rapid, explosive outbreaks in settings where people are in close quarters. It is extremely contagious, with a very small amount of virus enough to cause infection, and it can persist on surfaces and resist many common disinfectants. Illness is usually short-lived but unpleasant, and outbreaks can disrupt schools, hospitals, and travel. Virus Tracker surfaces available seasonal signals to support situational awareness.
Transmission
Norovirus spreads through contaminated food or water, contact with an infected person, or touching contaminated surfaces and then the mouth. Infected people shed large amounts of virus in vomit and stool, and can remain contagious for days after symptoms resolve.
Symptoms & clinical notes
Sudden onset of vomiting and watery diarrhea are hallmark symptoms, often accompanied by stomach cramps, nausea, and low-grade fever. Symptoms usually last one to three days, but dehydration is a risk, especially for young children and older adults.
Prevention & control
Thorough handwashing with soap and water is more effective than alcohol-based sanitizer against norovirus. Surface cleaning with bleach-based disinfectants, safe food handling, and staying home while symptomatic and for a couple of days after help limit spread.
Surveillance context
Outbreak surveillance relies on reports from healthcare facilities, schools, and food safety authorities, along with laboratory confirmation of clusters. Seasonal patterns typically peak in cooler months in temperate regions.
Live dataset
Key metrics
Active cases
170.9K
Deaths
390
How fast it's spreading
17.6%
RisingNorovirus — global infection heat map
Country shading reflects relative active-case intensity from the current Virus Tracker dataset for this pathogen. Hover countries on desktop for counts.
Darker red = more people currently sick.
Live dataset
Trajectory outlook
Projected case trend with a modeled confidence range.
Projected case trajectory for Norovirus, with a shaded confidence range, based on the current Virus Tracker dataset.
Illustrative estimateLive dataset
Top regions by active cases
The 3 tracked locations with the most active Norovirus cases in the current dataset.
Top 3 tracked locations for Norovirus by active cases, ranked highest to lowest.
Live dataset
Threat intelligence visuals
Threat matrix
How fast vs. how deadly
Each bubble is a threat. Bigger bubbles mean more people are currently sick.
Where this data comes from
11 of 15 sources are reporting normally.
- 11 healthy sourcesHealthy
- 4 sources downDown
- Data reliability
- 41%
- Confidence-adjusted exposure
- 69.5K
Overall threat level
Where it's hitting hardest
- United States96.7K active · score 24.9
- Japan42.7K active · score 23.4
- United Kingdom31.5K active · score 22.9
Dataset
Top affected regions
| Location | Active | Deaths | Trend |
|---|---|---|---|
| United States (US) | 96,657 | 210 | Stable |
| Japan (JP) | 42,714 | 95 | Stable |
| United Kingdom (GB) | 31,537 | 85 | Stable |
Frequently asked questions
How does norovirus spread?
Through contaminated food or water, direct contact with an infected person, and touching contaminated surfaces before touching the mouth. It spreads very easily because only a tiny amount of virus is needed to cause infection.
Is there a vaccine for norovirus?
No vaccine is currently approved for general use, though candidates are in development. Prevention relies on hygiene and sanitation.
How long does norovirus illness last?
Symptoms typically resolve within one to three days, but people can remain contagious for a few days after feeling better.
Does hand sanitizer protect against norovirus?
Alcohol-based hand sanitizer is less effective against norovirus than thorough handwashing with soap and water, which is the recommended precaution.
Is this page medical advice?
Virus Tracker provides aggregated outbreak monitoring for education and situational awareness. It is not medical advice, a diagnostic service, or a substitute for guidance from qualified health professionals or official public health agencies. Always consult licensed clinicians and authoritative sources for personal health decisions.
What does "outbreak activity" mean on Virus Tracker?
Outbreak activity reflects active-case burden relative to recoveries in our models. It helps compare stressed outbreak zones within the dataset—it is not a clinical score.
How often is this wiki updated?
Figures refresh on the site’s ingestion and revalidation schedule (typically about every 30 minutes in production). Timestamps on the dashboard snapshot indicate the last build of the underlying dataset.
Why might the heat map not match official government totals?
We merge multiple open sources and fallbacks; reporting lag, testing policy, and geographic coverage differ by country. Use national health ministries for authoritative case definitions.
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