Because the influenza virus is continuously evolving, the infection does not confer the infected person with lifelong protection, as is often the case with other infectious diseases. This is why there are annual flu epidemics, and why the flu vaccine has to be adapted every year and risk groups vaccinated every year. Vaccinated people normally develop a protective amount of antibodies within two to three weeks.
On the advice of the Dutch Health Council, people at high risk for complications of the flu are personally invited to see their family doctor for a free of charge vaccination.
The target group of the NPG programme comprises:
- persons aged 60 or over
- children and adults with certain conditions, namely:
- patients with abnormalities and functional disorders of the airways and lungs
- patients with a chronic heart disorder
- patients with diabetes mellitus
- patients with a chronic kidney disease
- patients who recently underwent a bone marrow transplant
- persons infected with HIV
- persons with reduced resistance to infection (e.g. because of (functional) asplenia, auto-immune disease, liver cirrhosis, chemotherapy or immunosuppressive medication
- children aged between 6 months and 18 years who are long-term salicylate users
- persons with a mental handicap living in residential homes