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  • Advice about influenza prevention and vaccine


Advice about influenza prevention and vaccine

Published Updated

Every year, 5 to 15 per cent of the population contracts influenza. Research shows that many people are infected without becoming ill, but they can infect others.

Illustrasjon: Folkehelseinstituttet.

Every year, 5 to 15 per cent of the population contracts influenza. Research shows that many people are infected without becoming ill, but they can infect others.

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Good hand and cough hygiene prevents infection. The seasonal influenza vaccine is recommended to people in the risk groups.

How is influenza transmitted?

The influenza virus is found in the respiratory tract. The incubation time is normally 2 days from infection to illness. The risk of infection is greatest if the infected person coughs or sneezes directly on another person so that the virus is transferred to healthy mucous membranes.

The virus can survive for a few hours outside the body and can also be transmitted indirectly through hands and objects.

Good habits to prevent influenza 

  • Good hand and cough hygiene prevents infection 
  • Use a paper handkerchief over your mouth and nose to protect others when you cough or sneeze. Throw the handkerchief away after use. Then wash your hands. 
  • Cough or sneeze into your elbow if you do not have a paper handkerchief available. 
  • Wash hands frequently and thoroughly, especially after you have been out in public. 
  • Hand disinfection with an alcohol hand rub is an option when hand washing is not possible, for example when traveling.

Who is the influenza vaccine recommended for?

For some, influenza can be life-threatening. Most at risk are those who have reached a certain age or who have a chronic underlying disease or condition that means the body cannot tolerate influenza very well. If you are among these risk groups, the vaccine against seasonal influenza is recommended:

  • Pregnant women after week 12 of pregnancy (2nd and 3rd trimester). Pregnant women in 1st trimester which belongs to an additional risk group may be considered for vaccination.
  • Residents in nursing homes and sheltered accommodation
  • Everyone aged over 65
  • Children and adults with: 
    • diabetes mellitus, type 1 og 2 
    • chronic respiratory disease 
    • chronic cardiovascular disease 
    • chronic liver failure 
    • chronic renal failure 
    • chronic neurological disease or injury 
    • immunodeficiency disorders 
    • severe obesity (BMI over 40) 
    • other severe or chronic illness evaluated on an individual basis by a doctor

Other groups

In addition, the influenza vaccine is recommended to the following groups: 

  • Health professionals with patient contact. These are largely exposed to infection, and if they become infected, they can be a significant source of infection for their patients. 
  • Household contacts of immunosuppressed patients should consider vaccination against influenza to protect the patient.
  • Pig farmers and others who have regular contact with live pigs. The main reason to vaccinate pig farmers is to protect pigs against influenza infection, thus preventing the development of new viruses among pig herds. 

Why are pregnant women a risk group?

Most pregnant women who get influenza recover without complications and without damage to the foetus. Pregnant women have a slightly increased risk for influenza complications such as pneumonia, compared to other healthy. This risk seems to increase throughout the pregnancy. If the mother develops serious complications, the foetus is at risk. It has also been shown that influenza during pregnancy increases the risk of stillbirth.

Vaccination of the mother during pregnancy can protect the baby against influenza shortly after birth.

More about why the vaccine is recommended to risk groups

Almost 1 million people in Norway belong to groups at increased risk for complications of influenza. It is estimated that an average of 900 people die each year in Norway as a result of influenza. The influenza vaccine could save many of these lives.

Influenza can cause pneumonia and worsening of chronic underlying diseases. With severe complications from influenza, hospitalisation is often needed. Some people have permanently impaired health after severe influenza.

Influenza vaccination 

  • results in fewer hospital admissions  
  • reduces the risk of complications and permanently impaired health
  • saves lives