Introduction
A gastrointestinal flu is not a flu illness caused by influenza viruses in the intestine, as the impression might be given. In the case of a gastrointestinal flu caused by viruses or bacteria, the pathogens nest and multiply in the intestinal mucosa, then upset the entire digestive process and also activate the immune system, which leads to inflammation of the intestinal mucosa. If bacteria are not found directly on site, their toxins or components of their sheath can also have the same effect on the mucous membrane of the gastrointestinal tract.
The other causes also all have inflammation as a trigger for the symptoms of gastroenteritis in common. In medical terminology, gastroenteritis is also known as gastroenteritis. Since in medicine, inflammation is always identified by the suffix “-itis”, it is already clear from the name that gastroenteritis causes inflammation of the stomach (=gast) and intestine (=enterum). As a result of the inflammation, the mucosal cells lining the intestine can no longer perform their function properly and the food components and absorbed fluids remain in the intestine instead of being absorbed into the body as usual. These food residues bind additional water in the intestine and the stool becomes increasingly thin – the typical diarrhoea develops.
Duration of a gastro-enteritis
The duration of a gastrointestinal flu depends on which pathogen caused the disease. Usually the symptoms begin with nausea and vomiting. In the course of the disease, diarrhea and abdominal pain also set in.
These often last the longest. If viruses, such as the rota or norovirus, are the trigger of the disease, the symptoms usually appear very suddenly with a rapid worsening. However, they only last for about 1 – 5 days on average.
Bacteria that can trigger gastroenteritis are for example Campylobacter, Salmonella or E. coli bacteria. If they are the trigger of the disease, the duration of the symptoms is usually between 1 – 2 weeks. However, Salmonella in particular can still be present in the body after the symptoms have subsided, and up to a few months can also be present in the bowel movements.
In addition, acute gastroenteritis may not heal completely and persistent symptoms such as nausea or diarrhea may occur. If this is the case, a doctor should be consulted. This doctor can clarify the cause of the persistent symptoms by examining the patient.
This may be an inflammation of the mucous membrane of the stomach, which is caused by the irritation of the stomach after a gastro-enteritis. On the other hand, it should also be ruled out whether parasites are present that can also cause long-lasting complaints. The duration of the illness depends on the severity of the gastro-enteritis and whether the doctor assumes viruses or bacteria as the cause of the illness.
If the symptoms begin very suddenly, without an obvious cause such as suspected food poisoning, a viral infection can be assumed. Patients are usually put on sick leave for the next 3 days. If the onset is gradual or after eating spoiled food, the patient can be put on sick leave for a week to 10 days.
The course of a gastrointestinal flu depends on the pathogens that caused the disease. If viruses are responsible for the infection, the symptoms start very suddenly. The first symptoms are rapidly worsening nausea, often followed by vomiting.
As the disease progresses, diarrhea and cramp-like abdominal pain may follow. However, the symptoms usually disappear as quickly as they came. Therefore, a viral gastro-enteritis usually ends after 1-5 days.
In contrast, the course of the gastro-enteritis, which is not caused by viruses but by bacteria, is somewhat more protracted. Here too, the symptoms begin in the upper gastrointestinal tract. The symptoms slowly creep in and gradually worsen.
Diarrhoea is often more pronounced in bacterial infections. This is due to the fact that some bacteria produce toxins that lead to increased salt excretion. The salt in the gastrointestinal tract binds water to itself, which makes the stool more fluid.
In addition, fever occurs more frequently as a side effect of gastro-enteritis caused by bacteria. Whether antibiotic therapy is necessary to cure the disease should be discussed with the family doctor. The bacterial infection of the gastrointestinal tract lasts for 1-2 weeks, and the symptoms gradually improve over the course of time.The incubation period describes the time between infection with the pathogens and the first appearance of symptoms.
It is, like the duration of the gastroenteritis, dependent on the type of pathogens. If viruses are the trigger of the disease, the symptoms appear shortly after infection. The incubation period for rotavirus is 1-3 days, for norovirus it is only 6 – 50 hours.
Among the bacteria, salmonella are the ones that lead to the fastest onset of symptoms. They are often absorbed through spoiled food. The first symptoms appear a few hours to a few days later, depending on the amount of bacteria ingested.
However, most bacteria have a longer incubation period. The incubation period of a Campylobacter infection is 2 – 6 days. The different E. coli bacteria cause the first symptoms between 2 and 10 days.
In the case of a travel infection, the pathogen ETEC is often involved. It leads to the well-known travel diarrhoea, which occurs for the first time 1-4 days after infection. The duration of the infection depends on the pathogen that caused the gastroenteritis.
Viruses usually have a duration of infection that only exceeds the symptoms by a few days. The norovirus, for example, is usually no longer infectious one week after the symptoms. In the case of bacteria, the duration of infection can be longer. Salmonella can still be excreted in the stool up to 10 weeks after the gastro-enteritis. It is very important to know that especially the intake of antibiotics leads to a longer duration of infection.