Norovirus symptoms typically last 1 to 3 days for most people, but the virus stays in your body and remains contagious for much longer. The full timeline, from first exposure to the point where you’re no longer spreading it, can stretch across several weeks.
Incubation Period
After you’re exposed to norovirus, symptoms usually appear within 12 to 48 hours. During this window you may feel completely fine, but the virus is already replicating in your gut. You can actually start spreading it to others before you realize you’re sick.
What the Acute Illness Feels Like
When symptoms hit, they tend to come on suddenly. Expect some combination of nausea, vomiting, watery diarrhea, and stomach cramps. Low-grade fever, body aches, and fatigue are common too. Vomiting is often more prominent in the first 24 hours, while diarrhea can linger a bit longer.
For otherwise healthy adults and older children, the worst is usually over within 1 to 3 days. Young children, older adults, and people with weakened immune systems sometimes take longer to recover and face a higher risk of dehydration. The biggest concern during the acute phase is fluid loss. If you can’t keep liquids down for an extended period, you may need intravenous fluids.
How Long You’re Contagious
This is where norovirus gets tricky. Feeling better does not mean you’ve stopped spreading the virus. You continue shedding norovirus in your stool for at least a few days after symptoms resolve, and in some cases for 2 weeks or more. That extended shedding period is a major reason norovirus spreads so efficiently through households, cruise ships, and schools.
The CDC recommends that food workers stay home for at least 48 hours after their symptoms stop. The same guideline applies to workers in daycares, healthcare facilities, and schools. If your job doesn’t involve food or vulnerable populations, 48 hours symptom-free is still a reasonable minimum before returning. Careful handwashing after using the bathroom remains important for weeks after recovery.
Why Norovirus Spreads So Easily
Part of the answer is sheer potency. As few as 18 viral particles can cause an infection, and a single episode of vomiting or diarrhea releases billions of them. That’s why one sick person in a household or shared space can quickly lead to an outbreak.
The virus is also remarkably tough outside the body. On hard surfaces at room temperature, norovirus can survive for 21 to 28 days in a dried state. It has been detected in carpets up to 12 days after contamination, even with regular vacuuming. On items like keyboards, computer mice, and telephones, a related virus remained detectable for at least 72 hours. Norovirus also resists heat up to 145°F, which means quick steaming or light cooking won’t reliably kill it. Shellfish, especially oysters, need to be thoroughly cooked to at least that temperature.
Cleaning Contaminated Surfaces
Standard household cleaners and alcohol-based hand sanitizers are not very effective against norovirus. Chlorine bleach solutions are the recommended option for hard surfaces. After someone vomits or has diarrhea, clean the area immediately, then disinfect with a bleach solution. Launder contaminated clothing and linens on the hottest available setting and dry them thoroughly.
Because the virus can linger on soft surfaces like carpet and upholstery for nearly two weeks, steam cleaning at high temperatures is more effective than vacuuming alone. Pay attention to high-touch objects like doorknobs, light switches, faucet handles, and toilet flush levers.
How Long Immunity Lasts
After a norovirus infection, your immune system does build some protection, but it’s limited. Early estimates suggested immunity lasted only 6 months to 2 years. More recent modeling from a study published in Emerging Infectious Diseases suggests protection against the same strain may last roughly 4 to 9 years.
The catch is that norovirus comes in many genetically distinct strains. Protection against one strain offers limited cross-protection against others, which is why you can catch norovirus multiple times throughout your life. The GII.4 group of strains causes the majority of outbreaks worldwide and evolves frequently, further reducing the durability of any immunity you build up.
Recovery and Hydration
There’s no antiviral medication for norovirus. Recovery is about managing symptoms and replacing lost fluids. Water, oral rehydration solutions, and clear broths are the priorities. Small, frequent sips work better than large gulps if nausea is still an issue. As your appetite returns, start with bland, easy-to-digest foods.
Most people bounce back fully within a few days and feel close to normal within a week, though some lingering fatigue is common. Children and older adults deserve closer monitoring because they can become dehydrated faster and may not communicate their symptoms as clearly. Signs of significant dehydration include very dark urine, dizziness when standing, dry mouth, and producing few or no tears when crying (in young children).