can you get norovirus more than once,

 

Overview

Norovirus infection can cause the sudden onset of severe vomiting and diarrhea. The virus is highly contagious and commonly spread through food or water that is contaminated during preparation or through contaminated surfaces. You can also be infected through close contact with an infected person.

Diarrhea, stomach pain and vomiting typically begin 12 to 48 hours after exposure. Norovirus symptoms usually last one to three days, and most people recover completely without treatment. However, for some people — especially infants, older adults and people with underlying disease — vomiting and diarrhea can be severely dehydrating and require medical attention.

Norovirus infection occurs most frequently in closed and crowded environments such as hospitals, nursing homes, child care centers, schools and cruise ships.

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Symptoms

Signs and symptoms of norovirus infection include:

• Nausea
• Vomiting
• Stomach pain or cramps
• Watery or loose diarrhea
• Feeling ill
• Low-grade fever
• Muscle pain

Signs and symptoms usually begin 12 to 48 hours after exposure to norovirus and last one to three days. You can continue to shed virus in your feces for up to two weeks after recovery. This shedding can last weeks to months if you have an underlying health condition.

Some people with norovirus infection show no signs or symptoms. However, they are still contagious and can spread the virus to others.

When to see a doctor

Seek medical attention if you develop diarrhea that doesn't go away within several days. Also, call your doctor if you have severe vomiting, bloody stools, stomach pain or dehydration.

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Causes

Noroviruses are highly contagious and are shed in the feces of infected humans and animals. You can get norovirus by:

• Eating contaminated food
• Drinking contaminated water
• Touching your hand to your mouth after your hand has been in contact with a contaminated surface or object
• Being in close contact with a person who has a norovirus infection

Noroviruses are difficult to kill off because they can withstand hot and cold temperatures and most disinfectants.

Risk factors

Risk factors for becoming infected with norovirus include:

• Eating in a place where food is handled improperly
• Attending preschool or a child care center
• Living in close quarters, such as in nursing homes
• Staying in hotels, resorts, cruise ships or other destinations with many people in close quarters
• Having contact with someone who has norovirus infection

Complications

For most people, norovirus infection usually clears up within a few days and isn't life-threatening. But in some people — especially children, older adults and people with compromised immune systems — norovirus infection can cause dehydration. Norovirus infection can cause severe dehydration, malnutrition and even death, especially in people who are older or immunocompromised, or in women who are pregnant.

Warning signs of dehydration include:

• Fatigue
• Dry mouth and throat
• Listlessness
• Dizziness
• Decreased urine output

Children who are dehydrated might cry with few or no tears. They might be unusually sleepy or fussy.

Prevention

Norovirus infection is highly contagious, and anyone can become infected more than once. To help prevent its spread:

• Wash your hands thoroughly with soap and water, especially after using the toilet or changing a diaper.
• Avoid contaminated food and water, including food that could have been prepared by someone who was sick.
• Wash fruits and vegetables before eating.
• Cook seafood thoroughly.
• Dispose of vomit and fecal matter carefully to avoid spreading norovirus by air. Soak up material with disposable towels, disturbing it as little as possible, and place it in plastic disposable bags.
• Disinfect surfaces that might have been contaminated. Use a chlorine bleach solution and wear gloves.
• Stay home from work, especially if your job involves handling food. You might be contagious for as long as three days after your symptoms end. Children should stay home from school or child care.

can you get norovirus more than once,

 

Norovirus

Norovirus causes diarrhoea and vomiting and is one of the most common stomach bugs in the UK. It's also called the 'winter vomiting bug' because it's more common in winter, although you can catch it at any time of the year.

Norovirus can be very unpleasant but usually clears up by itself in a few days.

You can normally look after yourself or your child at home.

Avoid going to your GP, as norovirus can spread to others very easily. Phone your GP practice or NHS 24 on 111 if you're concerned or need advice.

Symptoms of norovirus

You're likely to have norovirus if you experience:

• suddenly feeling sick
• projectile vomiting
• watery diarrhoea

Some people also have a slight fever, headaches, painful stomach cramps and aching limbs.

The symptoms appear one to two days after you become infected and typically last for up to two or three days.

How is norovirus spread?

Norovirus spreads very easily in public places such as hospitals, nursing homes and schools.

You can catch it if small particles of vomit or stools (poo) from an infected person get into your mouth through:

• close contact with someone with norovirus who may breathe out small particles of the virus that you then inhale
• touching contaminated surfaces or objects, as the virus can survive outside the body for several days
• eating contaminated food, which can happen if an infected person doesn't wash their hands before preparing or handling food

Norovirus is most infectious from the start of symptoms until 48 hours after all symptoms have stopped. You may also be infectious for a short time before and after this.

You can get norovirus more than once because the virus is always changing and your body is unable to build up long-term resistance to it.

Preventing norovirus

It's not always possible to avoid getting norovirus, but following the advice below can help stop the virus spreading. You should:

• stay off work or school until at least 48 hours after the norovirus symptoms have stopped
• avoid visiting anyone in hospital during this time
• wash your hands frequently and thoroughly with soap and water particularly after using the toilet and before preparing or handling food
• be aware alcohol-based hand gels don't kill the virus

Maintain basic hygiene and cleaning to help stop the spread of norovirus by:

• disinfecting any surfaces or objects that could be contaminated, using a bleach-based household cleaner.
• washing any items of clothing or bedding that could have become contaminated separately on a hot wash (60 °C) to ensure the virus is killed.
• not sharing towels and flannels
• flushing any poo or vomit in the toilet and cleaning the surrounding area with a bleach-based household cleaner
• avoiding eating raw, unwashed food
• only eating oysters from a reliable source as they can carry norovirus

What to do if you have norovirus

If you experience sudden diarrhoea and/or vomiting, the best thing to do is to stay at home until you're feeling better.

There's no treatment for norovirus, so you have to let it run its course.

You don't usually need to get medical advice unless there's a risk of a more serious problem.

To help ease your own or your child’s symptoms drink plenty of fluids to avoid dehydration.

You need to drink more than usual to replace the fluids lost from vomiting and diarrhoea – as well as water, adults could also try fruit juice and soup.

Avoid giving fizzy drinks or fruit juice to children as it can make their diarrhoea worse. Babies should continue to feed as usual, either with breast milk or other milk feeds.

You can also:

• take paracetamol for any fever or aches and pains
• get plenty of rest
• use special rehydration drinks, available from community pharmacies if you have signs of dehydration, such as a dry mouth or dark urine

If you feel like eating, try plain foods, such as soup, rice, pasta and bread.

Babies and young children, especially under a year old, have a greater risk of becoming dehydrated.

When to get medical advice

You don't normally need to see your GP if you think you or your child has norovirus, as there's no specific treatment for it.

Antibiotics won't help because norovirus is caused by a virus.

Urgent advice:Speak to your GP or phone 111 if:

• your baby or child has passed 6 or more watery stools (poo) in the past 24 hours or has vomited 3 times or more in the past 24 hours
• your baby or child is less responsive, feverish, or has pale or mottled skin
• you or your child has symptoms of severe dehydration, such as persistent dizziness, only passing small amounts of urine or no urine at all, or reduced consciousness – babies and elderly people have a greater risk of becoming dehydrated
• you have bloody diarrhoea
• your symptoms haven't started to improve after a few days
• you or your child have a serious underlying medical condition, such as kidney disease, and have diarrhoea and vomiting

Your GP may suggest sending off a sample of your stool to a laboratory to confirm whether you have norovirus or another infection.

can you get norovirus more than once

 

What Is Norovirus?

Norovirus is thought to be the most common cause of acute gastroenteritis (diarrhea and vomiting illness) around the world. It spreads easily through food and drink and can have a big impact on people's health.

Norovirus was originally called the Norwalk virus, after the town of Norwalk, OH, where the first confirmed outbreak happened in 1972.

On average, noroviruses cause 19 million to 21 million cases of acute gastroenteritis in the U.S. per year and send more than 450,000 people to the emergency room, according to the CDC. They cause more than half of all foodborne disease outbreaks each year. There are many types of noroviruses, and exposure to one type may not protect you from the others.

Although norovirus can strike year-round, it’s more common in the winter. People sometimes call it the “winter vomiting bug.” Noroviruses also are sometimes called food poisoning, because they can be transmitted through contaminated food. They aren't always the result of food contamination, though.

Norovirus Symptoms

If you come down with a norovirus infection, you'll probably go from feeling completely healthy to absolutely miserable within a day or two after being exposed. Typical symptoms include nausea, vomiting (more often in children), watery diarrhea (more often in adults), and stomach cramps.

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What Is the Norovirus?

The stomach flu isn’t really the flu at all. Meet the norovirus, and learn how it’s spread.

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Other norovirus symptoms include:

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

Most of these symptoms aren't serious, but diarrhea and vomiting can deplete your body of the fluid it needs, and you can become dehydrated. Children and the elderly are most susceptible to dehydration, as well as malnutrition from not getting enough nutrients.

If you have norovirus symptoms, your doctor can give you a stool test to confirm that you have the illness. But a norovirus diagnosis is usually made based only on symptoms.

How long is norovirus contagious?

It’s possible to shed the virus for up to 8 weeks. This means there’s a chance you could make other people sick. It usually gets less and less infectious over time.

In most cases, you can return to work or school after you have been symptom-free for 48 hours. Food service workers are generally encouraged to wait 72 hours before they handle food.

When should you call your doctor?

Call your doctor’s office if you still have symptoms after 3 days. Also, watch for symptoms of dehydration, which may also require a doctor’s attention.

In rare cases, vomiting could mean something more serious than norovirus. If your vomit is green or yellow, that could be a sign of a bowel obstruction. See a doctor right away.

Norovirus vs. Stomach Flu

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The Basics: Stomach Flu

Stomach flu is the nickname for an illness called viral gastroenteritis, a gut bug that's different from influenza.

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Norovirus is not related to the flu, which is an infection of the respiratory system that causes fever, chills, aches, and pains. In fact, there’s no such thing as stomach flu

Norovirus Causes and Risk Factors

People become infected with noroviruses when they eat or drink contaminated foods and beverages. Raw or undercooked oysters and raw fruits and vegetables have been blamed in some outbreaks. You can also get infected if you touch an object or surface that has been infected with the virus and then touch your nose, mouth, or eyes.

Noroviruses thrive in close quarters, such as restaurants, day-care centers, and nursing homes, because they are hardy and highly contagious. They can survive temperature extremes in water and on surfaces.

Once someone is infected from contaminated food, the virus can quickly pass from person to person through shared food or utensils, by shaking hands, or through other close contact.

When someone with the virus vomits, the virus can spread through the air and contaminate surfaces. The virus also spreads through feces, meaning someone who doesn’t thoroughly wash their hands after using the bathroom can pass it along. Dirty diapers can also harbor norovirus.

Young children, the elderly, and people who have weakened immune systems are particularly more vulnerable to noroviruses. The spread can be hard to control because it's contagious before symptoms appear. In other words, you can spread the virus before you know you’re sick.

Norovirus Diagnosis

If you have norovirus symptoms, your doctor can give you a stool test to confirm that you have the illness. But a norovirus diagnosis is usually made based only on symptoms.

Norovirus Treatment

Noroviruses, like other viruses, don't respond to antibiotics, which are designed to kill bacteria. No antiviral drug can treat norovirus, but in healthy people, the illness should go away on its own within 1 to 3 days.

Norovirus Complications

Most people don't have any long-term problems from the virus.

Norovirus infection can lead to dehydration, especially in children, older people, and those with weakened immune systems.

Symptoms of dehydration include:

• Dizziness when standing
• Dry mouth
• Peeing less
• Unusual sleepiness
• Fussiness or crying with few to no tears
• Listlessness
• Lethargy

To prevent dehydration, make sure to drink plenty of liquids, especially water and juices. Give children an oral rehydration solution (such as Pedialyte) to replace lost fluids and electrolytes. Avoid sugary drinks, which can make diarrhea worse, as well as alcohol and caffeinated beverages, which can dehydrate you further.

If severe dehydration develops, contact your doctor. Severe dehydration is sometimes treated with intravenous (IV) fluids.

Norovirus Prevention

Good hygiene is the key to preventing a norovirus infection, especially when you’re close to a lot of other people.

• Wash your hands often with soap and water for at least 20 seconds, especially after going to the bathroom or changing a baby's diaper, and before you prepare or eat food. Alcohol-based cleansers are not as effective as soap and water.
• Carefully throw away any contaminated items (such as dirty diapers).
• Wash raw fruits and vegetables thoroughly. Cook oysters and other shellfish before eating them.
• Clean and disinfect surfaces with a mixture of detergent and chlorine bleach after someone is sick.

If you have norovirus, don't prepare food for at least 2 to 3 days after you feel better. Try not to eat food that has been prepared by someone else who is sick.

can you get norovirus more than once

 Noroviruses are a group of viruses that can cause gastroenteritis. Gastroenteritis is an infection of the gut (intestines) which usually causes symptoms such as being sick (vomiting) and diarrhoea. Norovirus is the most common virus causing gastroenteritis in adults in the UK. In most cases the infection clears within a few days but sometimes takes longer. The main risk is lack of fluid in the body (dehydration). The main treatment is to have plenty to drink; this may mean special rehydration drinks. Also, once any dehydration is treated with drinks, you should eat as normally as possible. See a doctor if you suspect that you are becoming dehydrated, or if you have any worrying symptoms which are listed below.

IN THIS ARTICLE

• What is norovirus?
• How is norovirus spread?
• How do you catch norovirus?
• Norovirus symptoms
• How is norovirus diagnosed?
• When should I seek medical advice?
• Norovirus treatment
• Are there any complications?
• Preventing spread of infection to others
• Norovirus prevention

What is norovirus?

Noroviruses are a group of viruses that can cause infection of the gut (intestines), called gastroenteritis. Viruses are types of germs smaller than bacteria. Gastroenteritis usually causes symptoms of being sick (vomiting) and diarrhoea. Norovirus is the newer name given to the group of viruses that used to be known as Norwalk-like viruses and Norwalk virus. Noroviruses are also known as small round-structured viruses (SRSVs).

How is norovirus spread?

A norovirus present in the gut (intestines) of an infected person can pass out in their diarrhoea. It is easily spread from an infected person to another by close contact. This is usually because of the virus being present on the infected person's hands after they have been to the toilet. Surfaces or objects touched by the infected person can also allow transmission of the virus. The virus can be passed on if the infected person prepares food or if water is contaminated with norovirus.

Outbreaks of norovirus that affect many people can occur. For example, in hospitals, on cruise ships and in schools.

It usually takes 24-48 hours after first contact with norovirus before symptoms develop. This period is known as the incubation period for the virus.

How do you catch norovirus?

Norovirus is the most common virus causing infection of the gut (gastroenteritis) in adults in the UK. However, norovirus infection can occur in anyone of any age. You can get norovirus infection more than once because your body is not able to maintain immunity to norovirus infection for a long time once you have had it.

Norovirus symptoms

Feeling sick (nausea) is usually the first symptom. This is followed by diarrhoea which tends to be watery. You may also start being sick (vomiting) around the same time. Sometimes there are other symptoms such as:

• A high temperature (fever).
• A headache.
• Aching muscles in your arms and legs.

The symptoms tend to be relatively mild and short-lived, often only lasting one to two days. However, in a few people symptoms can last longer.

If symptoms are severe, lack of fluid in the body (dehydration) can occur. You should consult a doctor quickly if you suspect that you or your child are becoming dehydrated. Mild dehydration is common and is usually easily reversed by drinking lots of fluids.

Note: severe dehydration can be fatal unless quickly treated because the organs of your body need a certain amount of fluid to function.

For more information about symptoms, including dehydration, see the separate leaflets called Diarrhoea and Acute Diarrhoea in Children.

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How is norovirus diagnosed?

A sample of your stool (faeces) may be sent to the laboratory for testing during an outbreak of infection of the gut (gastroenteritis). This is to help identify the type and source of the infection. However, in most cases testing is not necessary because the treatment is usually the same for many causes of gastroenteritis.

When should I seek medical advice?

Children

Most children who have infection of the gut (gastroenteritis), including gastroenteritis caused by norovirus infection, have mild symptoms which will get better within a few days. The important thing is to ensure that your child has plenty to drink. In many cases, you do not need to seek medical advice. However, you should seek medical advice in the following cases (or if there are any other symptoms that you are concerned about):

• If your child is under the age of 6 months.
• If your child has an underlying medical condition (for example, heart or kidney problems, diabetes, history of premature birth).
• If your child has a high temperature (fever).
• If you suspect lack of fluid in the body (dehydration) is developing (see earlier).
• If your child appears drowsy or confused.
• If your child is being sick (vomiting) a lot and unable to keep fluids down.
• If there is blood in their diarrhoea or vomit.
• If your child has severe tummy (abdominal) pain.
• If your child has a weakened immune system because of, for example, chemotherapy treatment, long-term steroid treatment, HIV infection.
• Infections caught abroad.
• If your child has severe symptoms, or if you feel that their condition is becoming worse.
• If your child's symptoms are not settling - for example, vomiting for more than 1-2 days, or diarrhoea that does not start to settle after 5-7 days.

Adults

Again, most adults who have gastroenteritis, including gastroenteritis caused by norovirus infection, have mild symptoms which will get better within a few days. The important thing is to ensure that you have plenty to drink. In many cases, you do not need to seek medical advice. However, you should seek medical advice in the following cases (or if there are any other symptoms that you are concerned about):

• If you suspect that you are becoming dehydrated.
• If you are vomiting a lot and unable to keep fluids down.
• If you have blood in your diarrhoea or vomit.
• If you have severe abdominal pain.
• If you have severe symptoms, or if you feel that your condition is becoming worse.
• If you have a continuing high fever.
• If your symptoms are not settling - for example, vomiting for more than 1-2 days, or diarrhoea that does not start to settle after 3-4 days.
• Infections caught abroad.
• If you are elderly or have an underlying health problem such as diabetes, epilepsy, inflammatory bowel disease, kidney disease.
• If you have a weakened immune system because of, for example, chemotherapy treatment, long-term steroid treatment, HIV infection.
• If you are pregnant. 

Norovirus treatment

There is no special medication to treat norovirus. The aim is to make sure that you or your child have plenty of fluids to avoid lack of fluid in the body (dehydration) until their immune system has the time to clear the infection. Children with norovirus can usually be cared for at home. Occasionally, admission to hospital is needed if symptoms are severe, or if complications develop. For further information see the separate leaflets called Diarrhoea and Acute Diarrhoea in Children. 

Medication

Antibiotic medicines are not needed to treat norovirus. It is a viral infection so antibiotics will not be effective. See the separate leaflet called Diarrhoea Medicine for further information. 

Are there any complications?

Complications of norovirus infection are not very common. If they do occur, they can include the following:

• Lack of fluid (dehydration) and salt (electrolyte) imbalance in your body. This is the most common complication. It occurs if the water and salts that are lost in your stools (faeces), or when you have been sick (vomited), are not replaced by you drinking adequate fluids. If you can manage to drink plenty of fluids then dehydration is unlikely to occur, or is only likely to be mild and will soon recover as you drink. Severe dehydration can lead to a drop in your blood pressure. This can cause reduced blood flow to your vital organs. If dehydration is not treated, kidney failure may also develop.
• Lactose intolerance can sometimes occur for a period of time after norovirus infection. It is known as secondary or acquired lactose intolerance. Your gut (intestinal) lining can be damaged by the episode of infection of the gut (gastroenteritis). This leads to lack of an enzyme called lactase that is needed to help the body digest the milk sugar lactose. Lactose intolerance leads to bloating, tummy (abdominal) pain, wind and watery stools after drinking milk. The condition gets better when the infection is over and the intestinal lining heals.
• Irritable bowel syndrome is sometimes triggered by a bout of gastroenteritis.
• Persistent diarrhoeal syndromes may (rarely) develop.
• Reduced effectiveness of some medicines. During an episode of gastroenteritis, certain medicines that you may be taking for other conditions or reasons may not be as effective. This is because the diarrhoea and/or vomiting means that reduced amounts of the medicines are taken up (absorbed) into your body. Examples of such medicines are medicines for epilepsy, diabetes and contraception. Speak with your doctor or practice nurse if you are unsure of what to do if you are taking other medicines and have gastroenteritis.

Preventing spread of infection to others

If you or your child have norovirus infection, the following are recommended to prevent the spread of infection to others:

• Wash your hands thoroughly after going to the toilet. Ideally, use liquid soap in warm running water but any soap is better than none. Dry properly after washing. If your child wears nappies, be especially careful to wash your hands after changing nappies and before preparing, serving, or eating food.
• If a potty has to be used, wear gloves when you handle it, dispose of the contents into a toilet, then wash the potty with hot water and detergent and leave it to dry.
• Don't share towels and flannels.
• Don't prepare or serve food for others.
• If clothing or bedding is soiled, first remove any stools (faeces) into the toilet. Then wash in a separate wash at as high a temperature as possible.
• Regularly clean the toilets that you use, with disinfectant. Wipe the flush handle, toilet seat, taps, surfaces and door handles with hot water and detergent at least once a day. Keep a cloth just for cleaning the toilet (or use a disposable one each time).
• Stay off work, school, college, etc until until at least 48 hours after the last episode of diarrhoea or being sick (vomiting). Avoid contact with other people as far as possible during this time.
• Food handlers: if you work with food and develop diarrhoea or vomiting, you must immediately leave the food-handling area. For most, no other measures are needed, other than staying away from work until at least 48 hours after the last episode of diarrhoea or vomiting.

Norovirus prevention

The advice given in the previous section is mainly aimed at preventing you or your child from spreading norovirus infection of the gut (gastroenteritis) to other people if you are infected. However, in general, good hygiene is essential to prevent the spread of many infections to others and to reduce your chance of picking up infections from others.

Handwashing is the most important thing that you and your child can do. In particular, always wash your hands and dry them thoroughly and teach children to wash and dry theirs:

• After going to the toilet (and after changing nappies or helping an older child to go to the toilet).
• Before preparing or touching food or drinks.
• Before eating.

If you smoke, you should also wash your hands before smoking. The simple measure of washing hands regularly and properly is known to make a big difference to the chance of developing norovirus.