Norovirus causes sudden, intense vomiting and watery diarrhea that typically hit 12 to 48 hours after exposure. The illness is short but miserable, usually lasting 1 to 3 days before resolving on its own. Here’s what to expect if you or someone in your household gets it.
The Main Symptoms
The hallmark of norovirus is how fast it strikes. One moment you feel fine, and within hours you’re dealing with waves of nausea, vomiting, and loose or watery diarrhea. Stomach pain and cramping round out the core symptoms. Many people vomit or have diarrhea multiple times a day at the peak of the illness, which can leave you feeling completely wiped out.
Beyond the gut symptoms, norovirus often brings low-grade fever, headache, body aches, and chills. These tend to be milder than the gastrointestinal symptoms but add to the overall feeling of being seriously unwell. Fatigue can linger for a day or two even after the vomiting and diarrhea stop.
How Symptoms Differ in Children and Adults
Norovirus affects all ages, but the balance of symptoms shifts depending on how old you are. Children tend to vomit more, while adults tend to experience more diarrhea. The overall illness looks similar in both groups, but this difference matters because frequent vomiting in young children makes it harder for them to keep fluids down, raising the risk of dehydration faster.
Timeline From Exposure to Recovery
After you’re exposed to the virus, there’s a quiet window of 12 to 48 hours before symptoms appear. During this incubation period, you may feel perfectly normal. Then symptoms arrive suddenly, often peaking within the first 24 hours.
Most people recover within 1 to 3 days. However, you remain contagious even after you feel better. The virus continues to shed in stool for days after symptoms resolve, which is why hand hygiene stays important well into recovery. Avoiding food preparation for others for at least 48 hours after your last symptoms is a standard precaution.
Dehydration: The Biggest Risk
The symptoms themselves aren’t dangerous for most healthy adults, but the fluid loss from repeated vomiting and diarrhea can cause dehydration quickly. Signs to watch for include dark urine, dry mouth, dizziness when standing, and producing fewer tears (especially noticeable in children). In infants, a sunken soft spot on the head or going more than a few hours without a wet diaper are red flags.
Small, frequent sips of water or an oral rehydration solution work better than trying to gulp large amounts at once, which can trigger more vomiting. Young children, older adults, and people with weakened immune systems are most vulnerable to dehydration and may need medical attention if they can’t keep fluids down for several hours.
Norovirus vs. Food Poisoning
Because both cause vomiting and diarrhea, it’s easy to confuse norovirus with bacterial food poisoning. Two clues help you tell them apart: timing and duration.
Food poisoning from bacteria hits fast, usually within 3 to 6 hours of eating contaminated food. Norovirus takes longer to show up, with a slower buildup where you feel queasy and off before the vomiting begins, typically 12 to 24 hours after exposure. If your whole family gets sick a few hours after the same meal, food poisoning is the more likely explanation. If symptoms appear a day or two later, norovirus is the better bet.
Duration also differs. Food poisoning typically resolves within 24 to 48 hours. Norovirus tends to last 3 to 5 days from when you first feel unwell to when you’re back to normal, though the worst of it is usually over sooner. Norovirus also spreads readily from person to person, so if household members start dropping one by one over several days, that pattern points toward a virus rather than a shared contaminated meal.
Managing Symptoms at Home
There’s no specific treatment for norovirus. The illness runs its course, and the goal is to stay hydrated and as comfortable as possible while it does. Replacing lost fluids is the single most important thing you can do. Water, broth, and electrolyte drinks all help. Avoid sugary drinks and alcohol, which can worsen diarrhea.
Eating may be the last thing on your mind during the first day, and that’s fine. When you’re ready, start with bland, easy-to-digest foods like toast, rice, bananas, or plain crackers. Your appetite will return as the virus clears. Rest as much as you can, and don’t rush back to your normal routine. Even after the vomiting stops, your energy levels may take another day or two to bounce back.