You're contagious with stomach flu (viral gastroenteritis) from the start of symptoms until at least 2 days after they stop, but can remain infectious for up to two weeks, as the virus persists in stool for longer; strict hygiene, especially handwashing and avoiding food prep for 48 hours post-symptoms, is crucial to prevent spread.
Most people with norovirus feel better a day or two after their symptoms begin. But they're contagious for a few days after they recover. The virus can stay in the stool for two weeks or more after recovery.
People who have norovirus are still contagious for 48 to 72 hours after recovering. You should limit certain activities, but you may be able to resume others. To reduce your risk of spreading the stomach bug to others: Avoid preparing and serving food.
“If you can, try to avoid contact with anyone who has recently had vomiting or diarrhoea. If you are exposed to a sick person, wash your hands immediately and if you're caring for someone with norovirus, wash your hands every time you come into contact with them.
Hand sanitizer won't kill norovirus, so opt for good old soap and water, scrubbing thoroughly and vigorously for at least 20 seconds. Keep washing your hands regularly, especially after you have any contact with your partner or something they touched. They should be washing their hands regularly, too.
Self care
Signs and symptoms of norovirus infection may start suddenly and include:
Norovirus illness usually begins 24 - 48 hours after exposure, but can appear as early as 10 hours after exposure. Symptoms usually include nausea, vomiting, diarrhea, and stomach cramping. Sometimes people have a low-grade fever, chills, headache, muscle aches, and a general sense of tiredness.
The way a 24-hour stomach bug feels can be similar to other health issues like food poisoning or bacterial infections, making it difficult to identify without professional diagnosis. The initial impact of a 24-hour stomach bug is quite severe, disrupting day-to-day life significantly.
Norovirus is very contagious; it spreads very easily and quickly. You can get norovirus from sick people and through contaminated food, water, or surfaces. You are most contagious when you have symptoms of norovirus illness or during the few days after you feel better.
Nausea, vomiting or both. Stomach cramps and pain. Occasional muscle aches or headache. Low-grade fever.
There's no specific treatment for norovirus infection. Recovery generally depends on the health of your immune system. In most people, the illness usually resolves within a few days. It's important to replace lost fluids.
Norovirus is a specific, highly contagious "stomach bug," the leading cause of viral gastroenteritis (inflammation of stomach/intestines) with vomiting and diarrhea, often called "stomach flu" but unrelated to influenza; other stomach bugs can be bacterial or parasitic, but norovirus is known for rapid spread in crowds, with symptoms (12-48 hrs post-exposure) often severe but brief (1-3 days), emphasizing hydration and hygiene.
Norovirus is the biggest cause of illness from contaminated food in the U.S. The virus typically spreads when someone who has the virus touches food before serving it to someone else. Sometimes, certain foods, including oysters and other seafood, are naturally contaminated with norovirus.
While you have a stomach bug, you should be lying or sitting down as much as possible. Take it easy and give your body time to rest.
It's important to note that if diarrhea is caused by bacteria, your body needs to get rid of the bacteria first by letting diarrhea run its course. If they're taken too soon, anti-diarrheal medication can make symptoms worse and keep you from clearing the infection.
What to drink when you have the stomach flu
The green colour of poo, if someone has a gut infection, is usually caused by the bacteria salmonella, a parasite called giardia, or a virus called norovirus. Most gut infections do improve in five to ten days with self-care. Read more about food poisoning and gut infections here.
To kill norovirus, use bleach-based cleaners for surfaces and thoroughly wash hands with soap and hot water, as alcohol-based sanitizers are less effective; steam cleaning can also work on fabrics, and proper food handling (cooking shellfish, washing produce) prevents spread. Disinfect contaminated surfaces by first cleaning with detergent and hot water, then applying a diluted bleach solution (5-25 tablespoons per gallon of water) and letting it sit for 5 minutes before wiping.
The number of vomiting events ranged from 1 to 7, with 32% of subjects only vomiting once.
Cleaning toilet areas
When cleaning the toilet, always wear household rubber gloves and a plastic apron, if available. Disinfect the toilet seat with hot water, Disinfect by wiping down the toilet door handle, wash hand basin taps and toilet flush handle with a disposable cloth dampened with 0.1% bleach solution.
Norovirus is an extremely contagious virus.
Norovirus can survive on surfaces for up to two weeks.
To avoid gastro when a family member is sick, practice meticulous hand hygiene (soap & water for 20+ secs), disinfect contaminated surfaces (use bleach solution), isolate the sick person's belongings, and avoid sharing utensils, towels, or food, as the virus spreads easily through contact with vomit/diarrhea and airborne particles, with infectiousness lasting even after symptoms disappear.
Gastroenteritis. Gastroenteritis is often mistaken for stomach flu although it is actually an inflammation of the lining of the intestines caused by a virus, bacteria or parasites. Symptoms of gastroenteritis include diarrhea, abdominal pain, vomiting, headache, fever and chills.
Symptoms occur one to two days after you were exposed to the virus. Fortunately, they're usually over just as quickly, resolving in one to two days.