Top Nav Bar

Overview
Home > Diseases & Conditions > Viral Infections > Overview

Norovirus May Be Causing Your 'Stomach Flu'

By Jenilee Matz, M.P.H., Staff Writer

People often complain of the "stomach flu." But while some flu viruses, such as H1N1, can cause some stomach upset, the "stomach flu" often has another cause - the norovirus.

Basics on the norovirus bug
Norovirus, or Norwalk-like viruses, are a group of germs that cause the "stomach flu." Though it's often called stomach flu, norovirus is not the same virus that causes seasonal flu or H1N1 influenza. Illness usually lasts one to two days. Telltale signs are gastrointestinal symptoms, including:

  • Nausea
  • Vomiting
  • Diarrhea
  • Stomach cramps

Other symptoms may include:

  • Low-grade fever
  • Chills
  • Muscle aches
  • Headache
  • Fatigue

If you have norovirus, you may feel like you have "the flu." But with norovirus, you will not usually have coughing and congestion.

How you catch it
Norovirus is more common in cooler weather months, but you can come down with it any time of the year. It is very contagious, spreading easily from one person to another. That's why norovirus outbreaks often occur in crowded places like cruise ships, schools, nursing homes and hotels.

The virus is found in the vomit and stool of sick people. It is spread these ways:

  • Through food and liquids. You eat foods or drink beverages that are contaminated with the virus.
  • By touching contaminated surfaces. Norovirus can live on kitchen counters, doorknobs and toys. If you touch these surfaces then touch your mouth, you could get sick.
  • Through direct contact with a sick person. If you're taking care of a sick loved one, you could become ill.

Most people start to feel sick one to three days after getting infected. People who get the norovirus are contagious from when they start feeling sick until about three days after they're feeling better. Some people, though, can be contagious for as long as two weeks.

The road to recovery: watch for dehydration
Your symptoms should go away after one to two days. But, sometimes it can last up to 10 days.

The illness will clear up on its own without any medication. Norovirus is caused by a virus, and antibiotics do not work on viruses.

When you're sick, it's important to take in plenty of fluids to stay hydrated. Dehydration is serious and can come on quickly. It's especially dangerous for young children, seniors and people with chronic health conditions. To prevent dehydration:

  • Sip on fluids or suck on ice chips.
  • Drink beverages that contain electrolytes. Electrolytes are important nutrients that are lost through diarrhea and vomit. Broth-based soups, fruit juices and sports beverages contain both water and electrolytes. Your doctor may suggest an over-the-counter rehydration product, too.

Look out for these symptoms of dehydration in adults:

  • Decrease in urination
  • Dry mouth or throat
  • Dizziness when standing

Signs of dehydration in children may also include:

  • No tears when crying
  • Unusually sleepy
  • Irritability

Call your doctor right away if you notice any signs of dehydration. Someone who is severely dehydrated should be taken to the emergency room.

Prevention is key
Having the "stomach flu" is not fun. The best weapon against norovirus and other illnesses is frequent handwashing and good hygiene:

  • Wash your hands before eating and after using the bathroom, touching an animal, changing a diaper and caring for someone who is sick.
  • If you're sick, wash your hands often to prevent passing the illness to others.
  • Frequently clean countertops, doorknobs and other areas in your home that are touched often.
  • Rinse all fruits and vegetables with water before eating.
  • Don't share bed sheets, towels, clothes, dishes or utensils with a sick person.

Related Articles

Swine Flu: Preventing Dehydration

Five Ways to Keep Your Family Well This Winter

Stomach Virus? When to See a Doctor for an Upset Stomach

A Step-By-Step Guide to Handwashing

External Sources

Hart CA, Cunliffe NA, Nakagomi O. Diarrhoea caused by viruses. In: Cook GC, Zumla AI, eds. Manson¿s Tropical Diseases. 22nd ed. Philadelphia, PA: Saunders Elsevier; 2009.

Centers for Disease Control and Prevention. Norovirus. . Accessed November 11, 2009

National Digestive Diseases Information Clearinghouse. Viral gastroenteritis. . Accessed November 11, 2009

This article was reviewed and updated 08-01-2009.

Return to the previous page

Disclaimer: The text presented on these pages is for your information only. It is not a substitute for professional medical advice. It may not represent your true individual medical situation. Do not use this information to diagnose or treat a health problem or disease without consulting a qualified health care provider. Please consult your health care provider if you have any questions or concerns.

Copyright © 1999-2005 Medical Network Inc. All rights reserved. No part of the contents of this web site may be reproduced or transmitted in any form or by any means, without the written permission of the publisher. "HealthAtoZ.com" should be prominently displayed on any material reproduced with the publisher's consent.

We subscribe to the HONcode principles of the Health On the Net Foundation