When Is the Stomach Flu Contagious?

While you're most likely to pass it to someone else when you have symptoms or soon after you start to feel better, you may be surprised at how long the stomach flu is contagious: up to two weeks after you recover.

Adults can generally return to their daily activities after being symptom-free for 24 hours. It is assumed that, at this point, the greatest transmission risk has passed.

But that doesn't mean the risk is zero. The stomach flu is passed on very easily, and preventive measures should still be taken to keep others healthy as long as you may be contagious.

(Note: It's recommended that kids wait 48 hours after their last bout of diarrhea or vomiting before being around others.)

This article looks at the causes and symptoms of stomach flu, how the viruses are spread, when viral gastroenteritis is contagious, and what you can do if you or someone in your household is sick with stomach flu.

When Is Stomach Flu Contagious?

The contagious period is different depending on which virus causes the stomach flu.

• Norovirus: Symptoms appear one to three days after exposure. You're contagious as soon as symptoms develop and for up to two weeks after you feel better.
• Rotavirus: This virus is contagious even before symptoms appear and for up to ten days after you recover. Typically, symptoms start one to two days after exposure.
  

Symptoms of Stomach Flu

Common stomach flu symptoms include:

• Diarrhea, which is sometimes severe and watery
• Vomiting
• Nausea
• Stomach pain
• Fever
• Headache
• Body aches
• Loss of appetite
• Dehydration

Preventing dehydration is important, as you lose moisture through diarrhea, vomiting, and sweating due to a fever.

How Stomach Flu Spreads

Stomach flu is spread through contact with an infected person's stool or vomit. Common routes of infection for viral gastroenteritis are:

• Sharing eating utensils
• Eating improperly prepared foods
• Drinking contaminated water
• Kissing someone who is sick
• Shaking hands with someone who is sick

You can also catch it by touching a contaminated surface and then touching your mouth or something you put in your mouth. This is called fomite transmission.

Stomach Flu Prevention

To prevent the spread of viral gastroenteritis, you should:

• Wash your hands after using the bathroom or changing diapers, before and after preparing food, or when caring for someone who is sick.
• Use hand sanitizer when soap and water aren't available or in addition to hand washing.
• Thoroughly wash fruits and vegetables. To be extra safe, peel them.
• Cook food thoroughly.
• Don't allow sick people to prepare food or take care of others.
• Thoroughly clean and disinfect high-touch surfaces (countertops, doorknobs) and anything the sick person has touched.
• Wash linens and clothing the sick person has used.
• Try not to touch your mouth or face, and teach your children not to touch theirs (or yours).

Staying away from sick people and keeping yourself and your sick family members home can help keep stomach flu from spreading, as well.

Summary

Stomach flu (viral gastroenteritis) is caused by viruses like norovirus and rotavirus. Symptoms include nausea, vomiting, diarrhea, stomach pain, fever, and weakness.

Stomach flu may be contagious for a couple of days before you have symptoms and up to two weeks after symptoms have cleared.

The virus is spread by direct or indirect contact with a sick person's stool or vomit. This includes kissing or touching a sick person or coming into contact with contaminated objects, surfaces, or food.

To prevent the spread, isolate, wash your hands, cook food thoroughly, and disinfect items the sick person has touched.

A Word From Verywell

The stomach flu is unpleasant, but people recover without any complications. If you or someone you care about seems to be especially sick or symptoms linger for longer than expected, talk to your healthcare provider.

Meanwhile, being smart about cleanliness and limited contact can go a long way toward keeping the virus from spreading.