Flu

If you have the flu, you suddenly feel unwell. The flu is a respiratory illness caused by the influenza virus. You can catch the flu repeatedly because there are various types of flu viruses that keep changing.

Flu is somewhat different from a common cold, as you often feel more ill with the flu. The flu is contagious: you can transmit it to someone else, making them ill as well. The flu viruses are present in droplets of snot, mucus, phlegm, and saliva.

Where does flu occur?

The flu occurs all over the world. In the Netherlands, the flu appears every year, usually during the winter months; this is referred to as seasonal flu. The frequency of flu cases is different every year. The RIVM monitors the development of the flu virus through surveillance.

What are the symptoms?

The flu often begins very suddenly. Within a few hours, you may experience one or more of the following symptoms:

• High fever (38 degrees or more)
• Headache
• Muscle aches and fatigue
• Chills
• Cough
• Sore throat
• Difficulty breathing

How to prevent the flu?

You can prevent flu infection by applying hygiene measures, such as the following: touch your nose, eyes, and mouth as little as possible. Use tissues. Wash your hands regularly with soap and water, ventilate well and regularly clean door handles, taps and handrails.

Prevent the flu with the flu jab

If you are not in a high-risk group but would like to have a flu jab and your employer is a customer of KLM Health Services, please make an appointment with KLM Health Services in the autumn.

More information

Want to know more about the flu? Then visit the information page of the RIVM here: Flu | RIVM.

Change in our services: from 21 December 2025, vaccinations will only be available for (employees of) companies!