The gastrointestinal virus


The gastrointestinal virus causes gastrointestinal flu (gastroenteritis) and is characterized by nausea, vomiting and diarrhea (diarrhea). Usually this is a self-limiting disease, but it can also lead to more severe courses.

Symptoms of a gastrointestinal virus

Typical symptoms are:

  • nausea
  • Vomit
  • diarrhea
  • stomach pain
  • bloated stomach
  • Muscle aches
  • a headache

The symptoms are now explained in more detail below:

The symptoms that are caused by a gastrointestinal virus usually appear very quickly and very aggressively. Sudden nausea, severe vomiting, stomach pain and a bloated stomach (flatus) are among the classic symptoms.

Muscle pain (myalgia) or headache also occur rarely.

The symptoms usually appear a few hours after the infection, in rare cases it takes up to 48 hours for the infection to break out in a fulminant manner. However, in patients with a good immune system, the gastrointestinal virus may only cause mild stomach discomfort or a slight discomfort.

Caution should be exercised especially in young children and elderly patients. As a result of the surge of vomiting and the watery diarrhea, there is not only a loss of water but also a loss of so-called electrolytes, i.e. sodium, potassium, calcium, magnesium. Therefore, electrolyte imbalances and water deficiency (dehydration) are feared in small children, in older patients and in general in all people who have had the gastrointestinal virus for several days.

It is therefore important to consult a doctor or have a doctor come home if the symptoms persist in order to possibly give the patient a volume substitution, i.e. water enriched with various electrolytes. Such a volume substitution may be necessary, especially in older patients, in order to avoid consequential damage.

The lack of water can lead to a sharp drop in blood pressure (hypotension) and in the worst case to a functional impairment of the kidneys which in the worst case can be accompanied by kidney failure. However, this is only relevant if the patient has not consulted a doctor to obtain volume replacement after several days of severe vomiting or diarrhea.

In some patients, in addition to gastrointestinal complaints (gastrointestinal complaints), there is also a fever. As soon as the fever rises above 39 ° C, a doctor should be informed.

In summary, the gastrointestinal virus is associated with sudden abdominal pain, watery diarrhea and frequent vomiting. An asymptomatic course occurs only in rare cases, i.e. an infection with the gastrointestinal virus without any visible symptoms. Particular care should be taken with infants. On the one hand because they cannot precisely report their pain and discomfort, on the other hand because the gastrointestinal virus can have a much stronger effect on infants than on adults.

Read more about this under Burning in the stomach.

In very rare cases it can happen that parts of the intestine turn inside out due to the virus infection (intussusception). This can lead to the death of the affected intestinal area. If the parents notice increased crying and a tense stomach in their baby, they should see a doctor so that he can do an ultrasound to rule out intussusception.

Is there a gastrointestinal virus disease without diarrhea?

Basically, diarrhea is the main symptom of a gastrointestinal virus disease and all those affected suffer from it. If there is no diarrhea, it is probably due to another illness or the number of bacteria was so low that the immune system fought against the virus and therefore no symptoms such as diarrhea developed.


Important treatment options are:

  • Much rest
  • right nutrition
  • much liquid
  • only in severe cases: medication

What can I do?

There is no drug against the gastrointestinal virus and therefore no specific therapy. However, the general symptoms should be improved with equally general therapy. This general therapy for an infection with the gastrointestinal virus depends very much on the course of the disease but also on the patient's constitution. In middle-aged patients, one often waits one or two days, as the virus has usually been pushed back by the immune system until the patient no longer has any symptoms.

In the case of infants, on the other hand, the course is monitored more closely because on the one hand dangerous intussusception can occur, on the other hand there can be an enormous loss of water due to excessive vomiting or severe diarrhea.

The latter also happens frequently in older patients. It is possible that the patient should be given an intravenous (IV) infusion of saline solution, i.e. into the vein, for several days. Before doing this, however, you should always try to compensate for the lack of fluids by drinking more.

In general, the best therapy for a gastrointestinal virus infection for all patients, young and old, is to drink as much as possible. The minimum should be 2 liters per day because the body loses a lot of fluid due to the symptoms of the infection. However, since it is not only fluid that is lost, small amounts should also be attempted to eat. Eating soup or broth is essential here. In addition, the patient should drink juices to counteract an electrolyte imbalance.
If this is not enough, a powder can be bought in pharmacies after consultation with the doctor, which is dissolved in water and which contains all the important electrolytes.
As soon as the symptoms improve somewhat, the patient should also try to consume light carbohydrates such as toasted bread or dry rusks. In general, the patient should eat what he feels like the most. So it may well be that some patients prefer to switch directly to pasta instead of toast.
Nevertheless, it should be said that the gastric mucosa is very easily irritated after an infection with a gastrointestinal virus and that it is better to eat easily digestible foods such as potatoes for the first two days. There are no other therapy options for an infection with a gastrointestinal virus.

Do i have to go to the hospital?

Only in the rarest of cases do patients have to go to hospital, especially in the case of elderly patients, however, if the course is more severe, a hospital stay may be necessary if there is too much fluid loss. Above all, it is important that no antibiotics are administered in the case of a gastrointestinal virus. On the one hand, because antibiotics only work on bacteria, on the other hand, because many antibiotics attack the gastrointestinal mucosa even further and thus make healing more difficult. Even if it is annoying: The duration of a gastrointestinal virus infection cannot be influenced or shortened by any therapy, only the symptoms can be alleviated.

Read more about the topic under: Medicines for gastrointestinal diseases

Home remedies for a gastrointestinal virus

A normal gastrointestinal infection will go away on its own after a few days, but it is usually very uncomfortable for those affected. Fortunately, there are some home remedies that can help relieve symptoms (especially diarrhea). The two most important groups are so-called adsorbents and swelling substances.

Due to their surface structure, adsorbents can bind (adsorb) the viruses and bacteria and then be excreted together with the stool. The best-known adsorbents include pectins, healing clay, white clay and activated carbon. Pectin is a vegetable compound and is found in many fruits such as apples, bananas, carrots and apricots. In addition, there are high-dose pectin-containing foods in the pharmacy. The healing earth and the white clay must be dissolved in water or tea. Due to the very fine grain size and thus the large surface area, they surround the pathogens and thereby render them harmless. Activated charcoal can also be taken as a soluble powder or as a tablet and bind the viruses through its structure.

Read more on this topic at: Home remedies for gastrointestinal flu

Swelling substances have the ability to bind water and thus strengthen the consistency of the stool. In addition, the increase in volume envelops the pathogens and allows them to be eliminated more easily.

Warmth in the form of hot water bottles or warm, damp washcloths helps against stomach cramps, which often accompany diarrhea.

The so-called Uzara root contains substances that inhibit the muscular movements of the small intestine and have a general relieving effect. It eliminates abdominal cramps, normalizes bowel movements, shortens the time of diarrhea and reduces nausea and vomiting.

However, all of these home remedies only relieve symptoms and cannot shorten the duration of the illness.


What should you eat when you have a gastrointestinal virus?

The virus infestation causes inflammation of the lining of the stomach and small intestine (gastroenteritis). Therefore, those affected should avoid foods that can additionally irritate the stomach.

What you should eat:

  • Rusks: easy to digest, contains a lot of carbohydrates
  • liquid porridge made from semolina, rice or oatmeal
  • Pureed apples or applesauce: contain many lost vitamins
  • Broths and soups: supply of lost electrolytes such as sodium, potassium and calcium

In the acute phase, which is characterized by severe diarrhea, those affected often suffer from severe loss of appetite. In this case, care should at least be taken to ensure adequate hydration. The body excretes a great deal of water in the intestine in order to wash away the pathogens. It is therefore important to compensate for this deficiency by drinking a lot.

What you should drink:

  • unsweetened, lukewarm tea
  • one liter of water mixed with half a teaspoon of table salt and three teaspoons of dextrose / table sugar

The latter is a recipe from the World Health Organization (WHO). About three liters of this mixture should be drunk daily.

You should avoid:

  • hot, spicy, sweetened and acidic dishes: irritate the stomach
  • Hot, sugared teas: Sugar and heat irritate the stomach wall


How long does a disease caused by a gastrointestinal virus infection last?

A gastrointestinal virus infection is usually short-lived. The typical symptoms of gastrointestinal virus illness are nausea, vomiting, and diarrhea (diarrhea).

The nausea and vomiting usually set in suddenly in those affected and should subside after about two days. A short time later, diarrhea, sometimes severe, occurs. One then speaks of the typical clinical picture of vomiting diarrhea as a result of illness caused by a gastrointestinal virus. While nausea and vomiting disappear quickly, the symptoms of diarrhea can last a few days longer. However, this should not last a week.

In extreme cases, an infection can take longer and thus have more serious consequences for the body. The individual duration of an illness depends on the respective pathogen, the general state of health of the person affected (functionality of the immune system, nutritional status, other existing diseases) and age.

Contagion and incubation period

How long is there a risk of infection?

You are considered contagious as soon as you are infected with the virus and have it inside you. This means that those affected who do not show any symptoms can still be contagious to other people. The reason for this is that the virus is still in a state in which it reproduces within the body. This period is called the incubation period. At this stage, of course, those affected do not yet know that they are considered contagious.

The greatest risk of infection is in the acute phase of the disease, when the viral load is highest. But even after the symptoms have subsided, you are still contagious.

The pathogens are excreted in the stool and could be detected two to three weeks after the acute phase. However, the risk is steadily decreasing as the immune system kills the viruses and therefore the viral load in the stool decreases from day to day.

How long is the incubation period?

In medicine, the incubation period is the period between infection by a virus or pathogen and the appearance of the first symptoms. Incubation (Latin: incubare = "to hatch") means the rapid multiplication of pathogens until they have multiplied so much that they damage the body and trigger corresponding symptoms.

The typical gastrointestinal viruses that cause gastrointestinal flu are the norovirus and the rotavirus. These have an incubation time of around four to 50 hours.

The incubation time depends on the general health of the patient (especially the functionality of the immune system) and the so-called infectious dose. It describes the minimum number of virus particles that are necessary to trigger an infection. Ten to 100 viruses are sufficient for the norovirus. The problem with the incubation period is that those affected are already contagious without even knowing about it.

You can read more about this at: How is norovirus infection treated?

Causes of a gastrointestinal virus

The most common causes are:

  • Noro virus
  • Rota virus
  • contaminated food
  • Lack of hygiene

The causes are now explained in more detail below:

There are two gastrointestinal viruses that play a crucial role in causing gastrointestinal infections. These include the Noro virus on the one hand and the Rota virus on the other.

The Noro virus is an unenveloped RNA virus, just like the Rota virus. Since both viruses are not enveloped, it is particularly difficult to use disinfectants to remove the virus. The gastrointestinal viruses then break out of the disease, especially in the winter months.
The Noro virus in particular is feared as it is very contagious and can lead to severe diarrhea.

The virus is transmitted faecal-orally. This means that a patient who forgets to wash his hands after going to the toilet (i.e. comes into indirect contact with his feces) carries the virus on his hands and then passes it on to him when the second patient shakes hands. If this patient now puts his fingers to his mouth, he ingests the virus orally. Just a few virus particles are enough to trigger gastrointestinal flu in the next patient.
However, there is also the possibility of ingesting the gastrointestinal virus through contaminated food. Frozen strawberries or fried chicken can be the cause of the transmission of the gastrointestinal virus.

Read more on this topic at: Norovirus - How Dangerous Is It?

Another cause is lack of hygiene. In Germany, for example, a little boy triggered a minor epidemic by vomiting in the opera because he was infected with the gastrointestinal virus. All other opera-goers who then used the same toilet fell ill with the Noro virus within a few hours.

The symptoms usually go away after about 2 days, but the virus may persist in the intestine for a longer time and then lead to dangerous water loss (dehydration). In general, there are other different viruses that can be regarded as gastrointestinal viruses. These include, for example, the enteroviruses, astroviruses or the adenoviruses. However, since these rarely lead to gastrointestinal infections, the two main actors, i.e. the noro virus and the rota virus, are discussed here.


To get that in a diagnosis Gastrointestinal virus to identify the patient should best one Stool sample Hand it in to the doctor treating you. This can then be in a laboratory examined to identify the virus.

The Rota virus is done using a Immunassays proven, in rare cases also with the help of the retroviral polymerase chain reaction (RT-PCR). The Noro virus can be proven in the same way. Usually that's enough Family doctor however the clinically visible symptoms as well as the anamnese, i.e. the conversation with the patient, in order to make a suitable diagnosis.

Since the evaluation of the stool sample takes too long, the patient should also be asked if it has not yet been proven Gastrointestinal virus adequately treated and on Hygiene standards take care not to infect the people around him.

How do I know it's the norovirus?

The norovirus manifests itself symptomatically in severe nausea, gushing vomiting as well as diarrhea and accompanying abdominal cramps. As a rule, these are more pronounced than the normal gastrointestinal virus. In addition, those affected suffer from exhaustion, a general feeling of weakness, headache, muscle pain and a slight fever.

However, these symptoms are relatively unspecific and occur in almost all gastrointestinal diseases. To make sure that it is the norovirus, a stool sample can be submitted and examined by laboratory medicine. Usually the doctor can make the right diagnosis based on the symptoms and the conversation with the patient (anamnesis).

Also read on this topic: Symptoms of Norovirus Infection.

How do I know it's the rotavirus?

The rotavirus causes symptoms similar to the norovirus and is difficult to distinguish from it without precise laboratory medicine. Those infected by a rotavirus usually suffer from a severe and sudden fever.

The rotavirus mainly affects children under the age of 5 because they have not yet made antibodies against the virus. Usually there is immunity to the virus after two infections at the latest by the Rota virus.

What is the typical way of infection with a gastrointestinal virus?

The classic infection with a gastrointestinal virus occurs via the so-called fecal-oral route. The pathogens first get on the hands, then in the mouth and from there into the gastrointestinal tract. Those affected either excrete the virus with their stool or in the acute phase through vomiting.

If you come into contact with your faeces when you go to the toilet, for example, all objects that you touch afterwards will be infected by the viruses and are considered contaminated. These can be, for example, toilet flushes, door handles or water taps. If the person concerned only does insufficient hand washing or even omits this completely, the viruses can be passed on to the next person through direct hand contact. If it touches the mouth, the germs enter the stomach and intestines, where they multiply quickly.

Another possibility for infection with a gastrointestinal virus is via droplet infection. When those affected vomit, the viruses get into the air and can be inhaled by other people. The tricky thing about norovirus is that just a few particles (only about 10 viruses) are enough to trigger a disease.

The viruses can also be ingested through food. Food that is not heated is particularly dangerous. Therefore, salads or raw vegetables should be cleaned sufficiently before consumption. It is also recommended that seafood and frozen foods be cooked or fried well.

The frequency distribution of a gastrointestinal virus

Gastrointestinal viruses can basically occur anywhere and anytime. However, the probability of contracting a gastrointestinal virus increases by 30-50% in the winter months. Hospitals and nursing homes in particular have a very high frequency distribution, but kindergartens are also often affected. In general, children and elderly patients are much more likely to develop norovirus or rota virus than healthy middle-aged patients.


Unfortunately, there is no real prophylaxis against infection with the gastrointestinal virus. On the one hand, the viruses are very resistant because they have no shell that could be damaged by detergents and disinfectants. On the other hand, transmission, especially in hospitals, kindergartens and nursing homes, can hardly be counteracted.

Nevertheless, one should try to pay attention to hygiene as much as possible. After washing your hands, you should also disinfect your hands. Since the virus can also stick to doorknobs, on the train or on documents, hand disinfection should also be carried out in between. In addition, you should avoid reaching your mouth with your hands, as the germ finds its portal of entry into the intestine via the mouth. In addition, when using the toilet, the toilet should only be touched with toilet paper and the seat should also be covered with toilet paper so that there is no contact here either.

In addition, the following applies: Those who lead a healthy lifestyle, do enough sport and eat healthily are less at risk of experiencing the full symptoms than a patient who pays less attention to themselves. Stress and psychological stress also promote worse symptoms.

How can you prevent infection?

To avoid contracting a gastrointestinal virus, good hygiene should be observed. Frequent and, above all, sufficiently long hand washing protect against infection. As a time guide, we recommend around 30-45 seconds when washing your hands.

You can also get vaccinated against rotavirus since 2006 (please refer: Vaccination against the rotavirus) and thereby protect yourself against the virus. This is especially recommended for young children and newborns, as gastrointestinal flu can have more serious consequences for you than for adults. Unfortunately, no vaccination protection is known for the norovirus.

Those affected and their contact persons should pay particular attention to very good hygiene. After the symptoms have subsided, all textiles such as bed linen, towels and clothing that came into contact with the sick person should also be washed at at least 60 degrees. In addition, the bathroom and especially the toilet should be cleaned thoroughly. If a family member falls ill, it is advisable to use their own toilet if possible.


Infection with a gastrointestinal virus has a very good prognosis. Although the infection starts quickly and violently, the symptoms subside significantly after just 2 days. Above all, vomiting and diarrhea should be gone after 2 days, but there may be a certain feeling of exhaustion and a slight nausea.

Even small children have a very good prognosis as long as you ensure they are hydrated enough. In older patients, an infection with a gastrointestinal virus is not dramatic, but should be monitored more closely because the volume loss leads to drying out more quickly and in the worst case to kidney failure.In this case the prognosis is unfortunately very bad. Nevertheless, it should be said that an infection with a gastrointestinal virus is very harmless, as long as you take care of sufficient fluid intake and protect your body.

Is the pill safe for a gastrointestinal virus?

The pill is normally broken down into its effective hormones by the intestinal flora and then absorbed into the bloodstream through the intestinal mucosa in order to be able to develop its effect. Caution should be exercised if a person using an oral contraceptive such as the pill has a gastrointestinal virus. By vomiting, the pill can be spit out again.

The diarrhea causes the pill to not move along the intestinal walls long enough and the active ingredient (synthetic hormones) cannot be absorbed in sufficient quantities.

Vomiting and diarrhea within three to four hours of taking the pill prevent adequate contraceptive protection. The contraceptive is therefore practically not taken.

Gastrointestinal virus in pregnancy

Is the virus dangerous for my baby?

There is no direct danger to the baby from the virus, as the viruses only affect the mother's gastrointestinal tract and do not even reach the baby. The virus does not get into the bloodstream and therefore never has contact with the baby.

The only problem is the consequences of the symptoms, which can be harmful to both the mother and the baby. Due to the constant diarrhea and vomiting, the body loses a lot of fluids and minerals. This leads to a lack of water (dehydration), which weakens the mother's circulation and organ functions. In addition, the pregnant women suffer from severe loss of appetite or lose the food they have eaten through vomiting. The mother therefore suffers from a lack of energy, as hardly any nutrients are absorbed into the blood in the acute phase. However, this usually has no consequences for the baby because the symptoms of the gastrointestinal virus subside after a few days.

The severe diarrhea and abdominal cramps can promote labor, especially in the last trimester of pregnancy, which is why pregnant women with norovirus should definitely consult a doctor.

Can I breastfeed with a gastrointestinal virus?

Breastfeeding in and of itself poses no problems for the baby, because the pathogens (viruses) are not transmitted to the baby via the milk. It is only important that very good hygiene is observed before and during breastfeeding, because the child must not come into contact with the mother's stool or vomit. For this reason, hands and possibly also the breast should be thoroughly cleaned with warm water and soap before breastfeeding.

Breast milk, on the other hand, can even protect the infant from contracting the gastrointestinal virus. In the course of the infection, the mother produces antibodies from the gastrointestinal virus that try to prevent the pathogen from multiplying or even kill it. These antibodies are passed on to the baby through breast milk and affect the baby's intestinal flora in such a way that the pathogens cannot multiply in the intestine. It has been shown that breastfed children have fewer gastrointestinal infections than children who are not breastfed.