Norovirus: Types, Symptoms, Causes, Diagnosis And Treatment

Norovirus can readily spread from person to person. Learn the symptoms and treatment to decrease your chances of coming in contact with norovirus.

There is nothing that can ruin your entire vacation like a disease or infection. Don’t you hate it when you work all year and finally get some time to go to the desired destination, relax with loved ones and you catch an infection that ruins everything? Norovirus is just one example of these infections that can ruin your plans.

Norovirus: Types, Symptoms, Causes, Diagnosis And Treatment
Norovirus is intestinal and stomach viruses that are very contagious.

Norovirus is known for wrecking precious time of numerous people who go on a cruise, but it is also able to mess up your plans on dry land as well. In order to find out what norovirus is and how to treat it, keep reading this article.

What is Norovirus?

Norovirus infection is actually, a group of viruses which cause inflammation of the stomach and large intestine lining. Norovirus is the leading cause of gastroenteritis in the United States. Norovirus infection was originally called Norwalk virus because the first outbreak of this infection was recorded in Norwalk, Ohio in 1972[1].

Norovirus Misconceptions

Norovirus infections are sometimes called food poisoning but it should be noted that they don’t always occur due to food contamination. Additionally, norovirus is sometimes considered as stomach flu but this infection isn’t an influenza virus.

What Causes Norovirus Infection?

Norovirus infections are highly contagious and are shed in feces of infected animals and humans. This infection can be transmitted in several ways and they are:

  • Drinking contaminated water.
  • Eating contaminated food.
  • Being in close contact with a person who is infected by norovirus.
  • Touching your hand to mouth after you have been in contact with contaminated object or surface.

Some foods that are known for norovirus outbreak are raw or undercooked oysters, vegetables and fruits. Norovirus infections usually occur on cruise ships because they are hardy and highly contagious. This type of infection thrives in closed and crowded environment and besides cruise ships, it can occur in hospitals, nursing homes, schools, restaurants, daycare centers, etc.

When some person is infected by this virus, they can transmit it onto another person through shared utensils, food, shaking hands, or other types of close personal contact. It is difficult to deal with norovirus infection because it is able to survive in both hot and cold temperatures and is also immune to various disinfectants.

This virus is known as the Ferrari of the virus world because if it isn’t controlled properly it can spread like fire and cause an epidemic.

Norovirus Infection

Food, surfaces, and water contaminated with norovirus can cause outbreaks.

What are the symptoms of norovirus infection?

Symptoms and signs of norovirus infection are:

  • Muscle pain
  • Nausea
  • Low-grade fever
  • Vomiting
  • Malaise
  • Cramps or abdominal pain
  • Loose or watery diarrhea

Signs and symptoms of this infection usually appear about 24 to 48 hours after person’s first exposure to the virus and they last between 1 and 3 days[2]. Also, person may still continue to shed virus in their feces for up to 3 days after the recovery.

It is important to mention that some people don’t experience any signs or symptoms of this virus, and it doesn’t make them any less contagious. They can still spread the virus onto other people.

People who are infected usually go from feeling perfectly fine to feeling miserable within one day. Even though most symptoms aren’t really serious, this infection should be taken seriously. Vomiting and diarrhea can exhaust entire body and even lead to dehydration.

What are Risk Factors For Becoming Infected By Norovirus?

Risk factors for norovirus infection are:

  • Weak immune system.
  • Staying in hotels, restaurants, cruise ships, or other places with too many people in closed area.
  • Living or visiting places where food is handled in an unsanitary manner.
  • Living in closed quarters e.g. nursing home.
  • Living with a child who attends daycare center or preschool.

Do I Need Medical Help?

You should, definitely, seek help from your doctor if your diarrhea is persistent, meaning it doesn’t go or even decrease in several days. You should also consider contacting your doctor if symptoms you are experiencing become severe e.g. severe abdominal pain, dehydration, bloody stool, severe vomiting etc.

How is Norovirus Infection Diagnosed?

This infection is diagnosed based on symptoms you experience. Doctor may suggest testing a stool sample in order to identify the infection.

Naturally, when you see your doctor make sure you give them the most accurate information so they can do their job properly. Here is what you can do before you see a doctor due to norovirus infection:

  • Write down the list of all symptoms you are experiencing. You should add the approximate time when the illness began and the intensity of vomiting and diarrhea.
  • Make a list of all medications you are currently taking, including vitamins and other supplements.
  • If you think you will forget this information, then write down key information that will be useful to your doctor e.g. if you made any change in lifestyle or introduced new food ingredient to your diet. Your doctor needs to know as much as possible in order to rule out other infections or diseases and determine the right diagnosis.
  • You probably have some questions for your doctor and you should write them down to remind yourself in case you forget.

Vomiting and diarrhea is a common symptom of norovirus.

Are there any Health Complications Related to Norovirus?

Norovirus infection usually goes away within three days and isn’t dangerous. However, some people (usually children and elderly) experience severe symptoms, like vomiting and diarrhea which can lead to dehydration, malnutrition, and in rare cases even death[3]. Dehydration shouldn’t be neglected and it is recommended to consult a doctor whenever you or someone you know experience symptoms of the virus in order to prevent any further complications. Signs of severe dehydration are:

  • Decreased urine output
  • Fatigue
  • Dizziness
  • Dry mouth and throat
  • Listlessness – lack of energy

Are there any Medical Treatments for Norovirus?

There is no specific medical treatment for norovirus infection and the recovery time depends mostly on your overall health and immune system. As it was mentioned above, the infection is usually gone within three days.

When you are infected with norovirus it is very important to replace the fluid you are losing through vomiting and diarrhea. If you feel like you can’t drink any more fluids, then you can receive fluids intravenously.

If you are under the age of 65, then your doctor might suggest you purchase an over-the-counter anti-diarrhea medication.

Are there any Home Remedies for Norovirus Infection?

If you have young children in your home and they get infected by norovirus, it would be a good idea to buy commercially prepared oral hydration solution that will prevent them from dehydrating. Adults can treat this virus with broths and sports drinks.

NOTE: You should avoid drinking sugary drinks, like fruit juices and soft drinks, because they can make diarrhea even worse.

When it comes to vomiting, you should try with smaller meals and a bland diet. Some foods to consider are:

  • Crackers
  • Soups
  • Broiled vegetables
  • Bananas
  • Yogurts

Norovirus Prevention

Norovirus Prevention

Washing your hands with soap & water can help to prevent norovirus infection.

Norovirus infection is highly contagious, but it can be prevented. It usually occurs due to contaminated food, or drink, or even through the contact with infected person[4]. Here are some tips how to prevent norovirus infection from spreading:

  • Wash your hands thoroughly, especially after using a toilet or changing your baby’s diaper. Also, wash your hands before you cook any meal and before you eat.
  • Avoid contaminated water and food, especially food that is prepared by a person who is sick. Naturally, avoid eating in restaurants that don’t seem hygienic enough.
  • Wash fruits and vegetables thoroughly as soon as you bring them home from the store.
  • Make sure seafood you prepare is not raw or undercooked.
  • Dispose fecal matter and vomit carefully in order to avoid getting infected by this virus through the air. You should soak up material in disposable towels and place it plastic disposable bags.
  • Make sure you disinfect virus-contaminated areas with the bleach. Also, don’t forget to wear the gloves during the process.
  • If you notice you are infected by norovirus, then take a day off and don’t go to work. This is especially important if your job involves handling food. Also, if you notice your children are infected as well, they should stay home.
  • Naturally, if you are infected, which also means you are contagious, avoid traveling until symptoms go away.

Must Watch – Powerful Norovirus Spreads across America

Norovirus Statistics

  • Norovirus is responsible for 21 million cases of acute gastroenteritis.
  • It accounts for 50% of food-related infections in America, even though food isn’t the only cause of this infection.
  • 80% of norovirus outbreaks occur between May and November.
  • Norovirus causes 71,000 hospitalizations in the US annually.
  • 65% of ward closures in the US were the result of norovirus infection.
  • In the last two decades, there have been more than 200 cases of norovirus on the cruise ships.

Also ReadThe Difficulties Of Living With Iron Deficiency Anemia


Norovirus is a highly contagious infection and it can, sometimes, become epidemic. This virus is able to survive in hot and cold temperatures and even some disinfectants can’t destroy it. However, symptoms of this virus usually aren’t dangerous but if you notice they became persistent, feel free to contact your doctor.



Sam Kramer is a Registered Dietitian, Licensed Dietitian Nutritionist, Six Sigma Green Belt Certified, and Certified Sports Nutritionis

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