Influenza is a contagious disease caused by influenza A, B or C. With proper treatment, the disease can be shortened significantly so that you can quickly overcome the infection.

The virus attacks the respiratory tract and especially the lower respiratory tract can be affected. It is an extremely contagious disease that easily occurs in circulation at workplaces and institutions. It is usually not a dangerous disease, but for some elderly and people with weak immune system, serious complications can develop. Therefore, many are vaccinated against the disease.

The disease can affect all ages and at all times of the year. But high season is the winter season, where epidemics are seen from time to time.

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Symptoms of flu

Influenza can suddenly occur with high fever and chills, and in addition, sore muscles, headaches and generally bad form often occur. There can also be pain and coughing. You usually feel very sick and have to be in bed.

Some of the most common symptoms of flu can be seen in the table:

Muscle pain


Cold Tremors


Runny nose

Dry cough

Sore joints

Sore throat and difficulty swallowing


Generally bad shape

Chest pain

Lack of appetite

Influenza without fever

It varies how high fever you get during a flu infection, but often between 38 and 40 degrees. If you have any of the symptoms of the virus without having a fever, it may be another disease, such as colds. Sometimes it can be difficult to distinguish between the two diseases, but the flu usually follows worse and is more severe symptoms than a cold. The two diseases are caused by two different types of viruses and are therefore not linked to each other.

How long does the flu last?

This works differently from person to person. Usually, you will be ill for 4-7 days if it is an uncomplicated disease course. However, it is very normal that you will feel tired and unresolved long afterwards. Some may feel at a lower energy level for several weeks.

If the disease develops, such as pneumonia or sinusitis, the disease may last for a long time. If you develop any of these complications, consult a doctor. If you have not improved within a week, there may be a reason to seek a doctor in your own right.

With anti-flu medicine, you can reduce the time you feel ill. Tamiflu is a medicine that can inhibit the development of the virus. Read more about it further down the article.

Influenza infection

Viral disease is an extremely contagious disease, that acts in the respiratory tract and is therefore easily spread. The disease is spread, among other things, by sneezing and coughing, which can send virus particles into the air and on to other people. It can also be infected by hands, for example, if you have the hand in hand and then touch a handle that others touch.

How long does the flu infect?

The infection often spreads quickly because you can infect already before you get the symptoms of the disease yourself. Usually, you can infect another 1-2 days before the symptoms start, until one day after the fever is gone. However, children may carry the infection for a long time after the fever is gone.

Incubation time

Incubation time is typically 1-4 days. The incubation period covers the period from becoming infected until you get the symptoms. Therefore, it can be difficult to say exactly when you have been infected and in what way. For example, you may have been infected abroad or on a plane, and then get the symptoms several days after you are home again.

Influenza epidemic

Normally, when you have had an influenza virus, you will develop a resilience to just that virus. This means you do not get the same type of virus twice. Because the disease can develop through mutations, for some years it may come as a type that the population in general is not resistant to. Since the disease is also highly contagious, it is seen every five years that a real epidemic occurs. Here it will typically be up to 20% of the population who get the infection because there is no immunity to the new version of the virus. The same can be true if it is virus B. Since those who are vaccinated against the disease are vaccinated against virus A, more will be exposed to infection when the B variant is in circulation.

Treatment options

Because the disease is a viral infection, penicillin or other forms of antibiotics will not help cure the disease. Antibiotics only help with bacterial infections and therefore will not have any effect on this viral disease. If the symptoms of flu last more than a week, there may be signs that there is a bacterial infection such as pneumonia, sinusitis or ear infection. This can be treated with antibiotics if there are bacteria responsible for the infection.

Medicines against influenza

Although antibiotics do not want to help with virus infection, there are other types of medications that can relieve discomfort.

Tamiflu is a treatment for influenza that helps to shorten the course of the disease. It inhibits the virus by penetrating new cells, so new viruses can occur. Generally, older people or people in the risk group develop severe complications that are being discontinued.

In addition, common headache tablets with, for example, paracetamol may help keep the fever down and reduce muscle aches and headaches.

If you have a runny nose, a nasal spray can make it easier to breathe properly. Different types of cough medicine can help on dry cough so you can sleep better at night.


There is a vaccination against influenza must be given in October before the high season of the disease begins. The protection lasts only for 6 months and therefore you must have vaccination every year.

Usually, it is recommended to people who are more prone to serious complications of the virus or who are at greater risk of getting the disease. This includes:

  • Persons over 65 years old
  • Pregnant, who often experience worse symptoms than others
  • Chronically ill persons, eg. pulmonary patients or people with diabetes
  • Persons with impaired immune system
  • Personnel in nursing homes or in the health sector

What can you do?

There are many things you can do to get better while you’re sick.

  • Rest and keep calm while the disease is as bad. Then try to move easily
  • Sleep as much as possible
  • Drink plenty of fluid as you lose a lot of fluid when you have a fever
  • Avoid drinking alcohol and smoking as it may prolong the disease period
  • Take painkillers and fever-reducing medicines. But do not forget to be calm
  • Use host medicine, it can make you sleep better and calmer
  • Drink herbal teas if you have a throat and need relief
  • Avoid caffeinated drinks like coke and coffee as it can make it harder to sleep
  • Put your favorite series on the TV and enjoy as much as possible
  • Avoid working the days you carry the infection so you do not transfer it to others
  • If symptoms persist after a week, consult a physician to determine if bacterial complications have occurred.

3 myths about the flu

There are many myths about the viral disease that do not hold science. Here are 3 of the most common.

Myth No. 1: Vitamin C causes the disease to go away

No, it does not help to take large amounts of vitamin C. The body can only absorb a certain amount a day, everything beyond this is washed out of the system. It’s always good to get lots of vitamins and minerals, but there is no evidence that more C vitamins help remove the flu.

Myth No. 2: Influenza is a strong cold

Although some of the symptoms may coincide, the two diseases have nothing to do with each other. There are various types of viruses that are the cause of the diseases. In addition, influenza affects the lower respiratory tract, and in the worst case it affects the lungs where the cold affects the nostrils and the nose.

Myth No. 3: You are contagious only when you cough and sneeze

No, you can infect as long as you have the virus in your body. However, the infection often occurs by coughing and sneezing, where secretion comes from the throat, lungs and nose, which can be transported through the air to other people. But you can already infect the day before you get the symptoms, even if you are not sneezing or coughing yet.