Norovirus is a highly contagious virus that causes gastroenteritis, an inflammation of the stomach and intestines. This results in symptoms like diarrhea, vomiting, nausea, stomach pain, fever, headache, and body aches. The virus is often referred to as the “stomach flu,” although it’s not related to the influenza virus.

People can become infected by consuming contaminated food or water, touching contaminated surfaces and then placing their hand in their mouth, or by coming into close contact with an infected person. Norovirus is particularly hard to contain because it can survive on surfaces for a long time and it takes a very small amount of the virus to cause an infection.


There is no specific treatment for norovirus. People affected need to drink plenty of fluids to replace those lost from vomiting and diarrhea. Most people recover within a few days, but the very young, the elderly, and people with compromised immune function are the most at risk for severe complications.

Causes of Norovirus

Norovirus is an extremely infectious virus that primarily causes vomiting and diarrhea. Here are several causes of Norovirus:

1. Direct Contact: Infection often occurs by coming into direct contact with an infected person. This can happen if an infected individual handles food without washing their hands after using the restroom.

2. Consuming Contaminated Food or Water: Infection can also occur by consuming contaminated food or water. This often occurs when food is prepared by an infected individual who did not thoroughly wash their hands. Foods like raw or undercooked oysters and raw fruits and vegetables have been frequently associated with norovirus outbreaks.

3. Touching Contaminated Surfaces: Virus particles can live on surfaces for days or even weeks, so touching a contaminated surface and then touching the mouth can result in infection.

4. Airborne Particles: In some instances, norovirus particles can get into the air, such as when an infected person vomits, and being in close proximity can lead to inhalation of the virus.

Norovirus is resilient and resistant to many common disinfectants, which is why outbreaks in environments like hospitals, cruise ships, and schools are common. Certain practices can help prevent norovirus infection, such as washing hands properly and regularly, avoiding raw or undercooked food, and maintaining personal hygiene.

Risk Factors of Norovirus

Norovirus is a very contagious virus that can affect anyone. It is the most common cause of gastroenteritis, an inflammation of the stomach and intestines. Here some risk factors associated with Norovirus:

1. Age: People of all ages can get infected and sick with norovirus, but young children and older adults are most likely to experience severe illness.

2. Environmental Exposure: You are at risk if you come into close contact with someone who is infected with the virus, touch surfaces or objects contaminated with the virus, or eat food or drink liquids contaminated with the virus.

3. Season of the Year: Norovirus infection is most common in places with close quarters such as schools, childcare centers, nursing homes, and cruise ships, primarily during the winter months.

4. Weakened Immune System: People with weakened immune systems are at a higher risk of contracting norovirus.

5. Unhygienic Practices: Poor hand hygiene can increase your chances of getting infected. Failing to thoroughly wash your hands after using the bathroom or changing diapers, for example, can lead to infection.

6. Consumption of Raw or Undercooked Foods: The virus can be present in shellfish like clams, oysters, and mussels or on fruits and vegetables that have been contaminated during handling. Washing fruits and vegetables and fully cooking seafood can lower your risk.

It’s important to note that having been infected with norovirus in the past does not make you immune. You can get it again because multiple strains of the virus exist, and immunity to one strain is temporary and does not necessarily protect against other strains. It’s always vital to practice good hygiene to prevent the spread of norovirus.

Signs and Symptoms of Norovirus

Norovirus, often referred to as the “stomach flu,” usually manifests itself with the following signs and symptoms:

1. Nausea: You might have a strong urge to vomit.

2. Vomiting: The virus causes severe bouts of vomiting that may become exhausting.

3. Diarrhea: Watery or loose stools are typical symptoms.

4. Stomach pain or cramps: You may experience stomach discomfort or cramping.

5. Body aches or muscle pain: You might notice a mild to significant ache in your body or muscles.

6. Malaise: There’s usually a general feeling of discomfort or illness.

7. Headache: A common symptom includes mild to severe headaches.

8. Fever or chills: You might experience an elevated body temperature or chills. However, not everyone with norovirus has a fever.

9. Loss of appetite: You may not feel like eating.

The symptoms of norovirus usually appear within 12 to 48 hours after first exposure to the virus, and the person remains contagious for as long as two weeks after recovery. It should be noted that symptoms can be more severe in children, elderly people, and people with compromised immune systems. If symptoms are severe or persist for more than a few days, medical attention should be sought.

Diagnosis Norovirus

Norovirus, sometimes referred to as the winter vomiting bug, is a very contagious virus that causes gastroenteritis or inflammation of the stomach and intestines. This leads to symptoms such as diarrhea, vomiting, nausea, stomach pain, fever, headache, and body aches.

Diagnosis of norovirus normally involves the study of a patient’s symptoms, recent exposure (since norovirus often spreads in specific communities or environments), and in some cases, lab tests which require a stool sample to confirm the presence of the virus.

The condition is often self-limiting and tends to resolve itself in a few days. However, dehydration can be a risk due to the nature of the symptoms, particularly in vulnerable people such as the very young, the elderly, or those with other underlying health conditions. Hydration and rest are key components of treatment, as there is no specific medicine to treat norovirus.

Treatment of Norovirus

Norovirus is a highly contagious virus that causes gastroenteritis, an inflammation of the stomach and intestines. Treatment mainly involves managing symptoms while the body fights off the virus, as there’s not currently a specific drug to treat norovirus. Here are steps to manage and help recovery from a norovirus infection:

1. Hydration: The most common symptoms of Norovirus are vomiting and diarrhea, both of which can lead to dehydration. So, maintaining the water balance in the body is crucial. People can rehydrate by drinking plenty of fluids like water, broths, or oral rehydration solutions available at pharmacies. It is recommended to sip on small amounts of water frequently to avoid vomiting.

2. Rest: Allow your body to combat the virus by getting plenty of rest.

3. Eat Light: When you feel able to eat, start with bland, easy-to-digest foods like rice, toast, bananas, or apples.

4. Avoid Contagiousness: Norovirus is highly infectious. It can spread very quickly from person to person, especially in places like schools, nursing homes, or cruise ships. To avoid spreading the virus, you should remain isolated until at least 48 hours after your symptoms have stopped, regularly washing your hands with soap and water, and disinfect frequently touched objects and surfaces.

In severe cases, where the person cannot drink enough fluid to replace what they’ve lost due to vomiting or diarrhea, they may need to be given fluids via a drip in the hospital. Always consult a healthcare professional if you’re ill and have any concerns.

Remember, there is currently no vaccine to prevent norovirus infection or medication to treat it, so prevention through hand hygiene and food safety is very important.

Medications commonly used for Norovirus

Norovirus infection commonly resolves itself and often doesn’t require treatment. However, loss of fluids from vomiting and diarrhea can result in dehydration which may need treatment. Medications aren’t typically used to treat the virus itself, given it’s a self-limiting disease, but medications and treatments may be used to alleviate symptoms or prevent complications. These can include:

1. Oral Rehydration Salts or ORS: Over-the-counter rehydration solutions, such as Pedialyte, to replace lost fluids and electrolytes.

2. Anti-Diarrheal Medications: Medications such as loperamide (Imodium) can reduce the frequency of diarrhea, but should be used cautiously as they can prolong the virus in the body.

3. Antiemetic Medications: In some cases where vomiting is severe, doctors may prescribe antiemetic medication to control vomiting, such as ondansetron.

4. Intravenous Fluids: In severe cases, hospitalization might be required to receive fluids through a vein (intravenously) to prevent dehydration.

Please remember that it’s essential to consult with your healthcare provider for advice and treatment, do not self-medicate without professional guidance.

Prevention of Norovirus

Norovirus is highly contagious and is primarily spread through direct contact with an infected person, consumption of contaminated food or water, or by touching contaminated surfaces and then putting your hand in your mouth. Prevention measures can be done, including:

1. Practice Good Hygiene: Washing hands thoroughly and frequently, especially before preparing or eating food, after using the bathroom, and coming into contact with possibly contaminated environments.

2. Clean and Disinfect Surfaces: If you know someone has been ill, it’s important to thoroughly disinfect any potentially contaminated surfaces. Noroviruses can survive on surfaces for days or even weeks.

3. Handle and Prepare Food Safely: Always wash fruits and vegetables thoroughly, and cook oysters and other shellfish thoroughly before eating them. Noroviruses are quite resistant and can survive temperatures as high as 140°F.


4. Limit close contact with infected people: Avoid sharing food, utensils, or even towels with anyone who shows symptoms of being sick. Isolate the sick person to a separate restroom to minimize spread through shared facilities.

5. Use Personal Protective Equipment: In cases where someone is already sick, using gloves and masks can prevent the spread of germs.

6. Stay at Home: If you’re diagnosed with norovirus infection, it’s advisable to stay at home and isolate yourself to avoid spreading it to others.

7. Use appropriate laundry washed and dried practices: Norovirus can also survive on clothing and linens, so all potentially contaminated laundry should be washed in hot water and dried on high heat. It’s recommended to wear gloves while handling contaminated laundry.

Remember, norovirus immunity doesn’t last long, a few months to a few years, so these practices need to be maintained.

FAQ’s about Norovirus

1. What is Norovirus?
Norovirus is a highly contagious virus that causes vomiting and diarrhea. It’s the most common cause of acute gastroenteritis, which is inflammation of the stomach, intestines, or both. It spreads rapidly and easily, especially in places like daycare centers, nursing homes, schools, and cruise ships.

2. How is Norovirus Spread?
Norovirus is usually spread through direct contact with an infected person, touching a surface or object contaminated with the virus and then touching your face, or consuming contaminated food or water. The virus can survive for days or even weeks on surfaces.

3. What are the symptoms of Norovirus?
The main symptoms of norovirus are vomiting, diarrhea, stomach pain, and sometimes fever. These symptoms usually develop 12 to 48 hours after being exposed to norovirus and can last 1 to 3 days. Dehydration can occur from these symptoms, especially in young children, the elderly, and people with other illnesses.

4. How is Norovirus diagnosed?
There are tests for norovirus, but they are not commonly done. The diagnosis is usually made based on the symptoms, especially if norovirus has been identified in the community.

5. What is the Treatment for Norovirus?
There is no specific medicine to treat people with norovirus illness. The best way to treat it is by drinking plenty of fluids to prevent dehydration, getting rest, and eating light, easy to digest foods.

6. Can Norovirus be Prevented?
Yes, the best way to prevent norovirus is to practice good hygiene. This includes washing hands thoroughly, especially after using the toilet and before eating or preparing food, avoiding sharing personal items, and cleaning and disinfecting surfaces regularly.

7. Are there Vaccines for Norovirus?
Currently, there is no vaccine to protect against norovirus, but developments are underway.

8. Can one get infected with Norovirus more than once?
Yes, immunity to norovirus is often temporary, so you can get sick from it multiple times throughout your life. It’s also possible to get infected with different strains of the virus.

9. Who is at risk for severe disease from Norovirus?
Young children, the elderly, and people with other serious illnesses can have severe or prolonged symptoms from norovirus infection because their immune systems might not be strong enough to fight off the virus.

10. What should I do if I suspect I have Norovirus?
If you suspect you have norovirus, you should stay at home and avoid contact with others to prevent transmitting the virus. Keep good personal hygiene and clean and disinfect any potentially contaminated surfaces. If symptoms persist or you are unable to keep fluids down, consult a healthcare professional.

Useful links

Norovirus is one of the most common causes of acute gastroenteritis worldwide. These viruses are characterized by their rapid onset of symptoms, which include nausea, projectile vomiting, abdominal pain, and in some cases, diarrhea. It is commonly known as “stomach flu” and outbreaks are often seen in communal settings such as cruise ships, hospitals, and nursing homes.

To learn more about Norovirus and access various research materials, please visit the following links from credible journals:


Please note that you might encounter a paywall on some websites. If that’s the case, you might be able to access the articles through institutions such as universities or libraries, alternatively, you can directly contact the authors and politely request a copy of their work.

Complications of Norovirus

Norovirus is a highly contagious virus that causes gastroenteritis, an inflammation of the stomach and intestines. Though it’s often referred to as a “stomach flu”, norovirus is not related to the influenza virus.

Primary complications of norovirus can include:

1. Dehydration: This is the most common and serious complication of norovirus. It occurs when your body loses more fluids and salts than it can replace. Symptoms include dry mouth and throat, dizziness, and decreased urination. In severe cases, dehydration can require hospitalization.

2. Malnutrition: If you’re unable to eat or keep food down for several days, you may not get all the nutrients you need, leading to malnutrition.

3. Secondary infection: Less commonly, you may experience secondary bacterial infections as a result of norovirus. This happens when the virus so weakens your immune system that other pathogens can take hold.

4. Chronic post-infectious irritable bowel syndrome: In some cases, after the norovirus infection has cleared up, people can continue to experience symptoms like diarrhea, stomach pain and bloating, known as post-infectious irritable bowel syndrome.

5. Spread to others: Because norovirus is highly contagious, it’s a significant public health concern. It spreads easily in crowded places like hospitals, nursing homes, schools and cruise ships.

For most healthy adults, norovirus is a short-term illness that clears up in a few days. However, for infants, older adults, and people with underlying health conditions, it can be serious or even life-threatening. It’s vital to take steps to prevent its spread and to seek medical attention if your symptoms don’t improve or if you become seriously dehydrated.

Home remedies of Norovirus

Norovirus, often called “stomach flu,” is a fast-spreading viral infection that primarily affects the stomach and intestines, causing gastroenteritis. Common symptoms include vomiting, diarrhea, nausea, and sometimes fever and muscle pain.

It’s important to note that there is currently no specific medicine to treat people with norovirus illness. Antibiotics won’t work because they fight against bacteria, not viruses like noroviruses.

However, you can take steps at home to help alleviate symptoms and prevent dehydration, which is the main concern with norovirus:

1. Stay Hydrated: This is the most important treatment. Drink plenty of fluids such as water, broths or oral rehydration solutions such as Pedialyte, especially if you are vomiting or have diarrhea.

2. Rest: Your body can fight off the virus more effectively when it’s well-rested.

3. BRAT Diet: Once you can hold liquids down, you can start to reintroduce bland foods into your diet. BRAT stands for Bananas, Rice, Applesauce, Toast. Start with these and gradually reintroduce more foods as you feel better.

4. Avoid Dehydration: Dehydration can be dangerous, especially for infants and the elderly. Look out for signs including decreased urination, dry mouth, dizziness when standing, or crying without tears in infants.

5. Hand Hygiene: Washing your hands frequently with soap can help prevent the virus from spreading to other people in your household.

Although these home remedies can help to alleviate symptoms, if you, or the person you’re caring for, become significantly dehydrated, can’t keep liquids down, show symptoms of bloody vomit or stools, or if symptoms persist for longer than a few days, it’s important to seek medical attention.

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Last Update: January 4, 2024