Influenza • Symptoms & Influenza Vaccination

The flu (influenza) is a viral disease that occurs mainly in the autumn and winter months. In most cases it is straightforward. Which symptoms are typical and how you can prevent the flu with a vaccination.

The flu (influenza) is a widespread viral disease that occurs as a so-called flu wave during the winter months. This seasonal flu is mostly caused by group B flu viruses. In addition to increased flu cases, a pandemic can also occur, most recently during the “new flu”, the so-called swine flu.

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Vaccinations recommended by STIKO

Flu often shows up through these symptoms

The incubation period, i.e. the time from infection to the outbreak of the flu, is between 18 hours and three days. Even at this time there is a risk of infection, even if there are no symptoms of flu. Viruses can still be detected in the sputum (secretion) of adults – up to two weeks in children – up to a week after infection. Even with a favorable course and when the flu symptoms have subsided, those affected can still infect other people with the flu.

Typical flu symptoms are:

While the flu comes on more suddenly and is almost always associated with a high fever, the cold starts slowly and the fever is not particularly high, if at all.

Symptoms with a complicated course

The flu is usually straightforward. Complications can rarely arise in the course of the disease. People with an underlying illness or a weak immune system, the elderly, or pregnant women are slightly more likely to experience complications from the flu. Above all, the additional infection with bacteria (superinfection) causes sometimes severe courses.

The following flu complications can occur:

No immunity after surviving the flu

Influenza pathogens change their genetics and mutate again and again, which is why complete immunity from a flu that has already been through is not possible. The pathogens remain very similar, which is why the flu is often less severe in adults than in young people or children due to their immunological memory.

Influenza: causes and risk factors

The cause of the flu is an infection with influenza viruses. There are three groups of flu viruses: Influenza A, B and C. Influenza viruses of group C only cause a mild flu, which is often not perceived as flu, but rather as a cold. Viruses of group B, on the other hand, are responsible for the annual, seasonal flu in the cold and wet seasons. Influenza A viruses cause severe flu illnesses that can develop into flu waves or pandemics.

Direct and indirect infection with the flu

Infection with influenza pathogens occurs very often through droplet infection when sneezing or coughing (direct infection). Infection with the flu is also possible through indirect contact. The reason: Influenza viruses can still be infectious outside the body for a few days. For example, flu viruses are often spread through the palms of the hands (after sniffing into the hand). You can therefore catch the flu through door handles, tables, handrails in public transport and all objects that are touched by many people.

It makes sense to hold your arm over your mouth when you sneeze or cough. This is to prevent other people from directly contracting the flu. In addition, you reduce the risk of a droplet infection by not coughing into the room, but into the crook of your arm.

The role of the immune system

Contact with influenza viruses does not necessarily lead to flu. The severity and course of the flu vary from person to person, even if the flu was caused by the same type of pathogen. The immune system also plays a major role in this. The immune system is often weakened in stressful situations, with prolonged, nutrient-poor diet, during pregnancy or during illnesses.

As people get older and have had influenza, they usually become more resilient to the flu. The immune systems of babies and toddlers have not yet had any or very few influenza illnesses. That is why they catch the flu particularly quickly. In old age, the immune protection built up in the course of life decreases somewhat, so that the flu can be more severe in older people.

Influenza diagnosis: rule out other diseases

Anyone who goes to the doctor with the typical symptoms of a viral flu will often be diagnosed with flu after a detailed discussion (anamnesis) and, if necessary, a physical examination.

A nasal swab or throat swab with a long cotton swab can be used to make a clear diagnosis of the flu. The smear is carried out when a clear diagnosis is necessary, for example in pregnant women or people with an underlying disease, or to clearly determine the type of virus. Taking the swab is a little uncomfortable, but usually not painful.

There is a compulsory report for influenza

The flu is a reportable illness in Germany. Therefore, the doctor will inform the health department that a flu case has been diagnosed in the practice. The main purpose of reporting the flu is to control flu waves or flu pandemics.

This is how flu is treated

The best therapy for the flu is bed rest, which should be kept for up to three days after the fever has ended. Pain-relieving medications are suitable for flu pain, and certain active ingredients such as ibuprofen also reduce fever. Children and adolescents should only be given pain medication after consulting a doctor. Medicines containing the active ingredient acetylsalicylic acid should never be taken by children and adolescents during the flu. If you have the flu, taking acetylsalicylic acid in young people can lead to Reye’s syndrome. The very serious illness damages the liver and brain and leads to death in about half of all cases. Signs of Reye’s syndrome are convulsions, severe vomiting, rigidity and an early coma.

For a persistent cough with the flu, remedies with the active ingredient codeine can be prescribed. Expectorant drugs also help to alleviate some of the respiratory problems. Sufferers should ensure they are drinking enough fluids during the flu. A good supply of vitamins, especially vitamin C, through food or with the help of vitamin preparations, also supports the body and the immune system.

Superinfection with bacteria

Occasionally there is an additional infection with bacteria. In the so-called superinfection, antibiotics are therefore also given as a therapy. The superinfection is a complication in the course of the flu. Getting to grips with it is very important as the body is already weakened by the viruses.

Course and complications of influenza

Depending on the severity of the disease, the flu can last up to two weeks if it is uncomplicated. An uncomplicated course means that there is no other underlying disease, those affected are not pregnant or the immune system was weakened for other reasons before the flu. In addition, no other illnesses should occur during the flu. Serious complications can be pneumonia, myocarditis or pericarditis, toxic shock syndrome or Reye’s syndrome.

Preventing the flu: how to protect yourself from influenza viruses

Infection with the pathogens of influenza occurs through droplet infection, either directly or indirectly via surfaces with flu viruses. During the flu season, people who cough are best avoided and washed hands thoroughly with soap and water. In the winter months it doesn’t hurt to clean your hands a little more often than usual and not to touch your face. Those who are sick themselves should stay at home so as not to infect other people.

Strengthen the immune system – prevent the flu

A healthy, active immune system is also an important factor in preventing flu. The immune system can be strengthened by reducing stress (for example with the help of relaxation techniques such as yoga), eating a healthy diet rich in vitamins – even in the winter months – and exercising regularly in the fresh air. Staying in dry, warm rooms dries out the mucous membranes and makes the body susceptible to viruses.

Influenza vaccination protects

To prevent the flu, there is the possibility of getting vaccinated. Autumn is the best time to have the flu vaccination in order to have the best possible protection during the flu season (usually January to March). The flu vaccination must be repeated every year. It protects against the most common types of flu, but cannot provide all-round protection. Flu is possible despite vaccination, but much less likely than without it. In addition, the flu often runs rather easily after a vaccination.

The Standing Vaccination Commission (STIKO) of the Robert Koch Institute advises the following groups of people to be vaccinated against influenza:

  • People who are 60 years and older
  • Pregnant women from the 2nd trimester of pregnancy, in the case of previous illnesses also in the 1st trimester
  • Children, adolescents and adults with an increased health risk from chronic diseases
  • Residents of old people’s or nursing homes
  • People at greatly increased risk, for example hospital staff
  • People with direct contact with poultry and wild birds

Depending on the travel destination and state of health, a flu vaccination may generally make sense before going on holiday. People with a chicken protein allergy should not be vaccinated against the flu because the vaccine is made in chicken eggs.

Preventing a cold: tips for a strong defense

Source: Lifeline | Das Gesundheitsportal by

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