If you are not yet 65, both the insurer and the mutual society are obliged to offer you health care insurance. (art. 206, law of 4 April 2014)
Please note that the costs related to the disability or illness existing at the time the insurance is taken out may not be covered by the insurance because the risk is realised.
The insurer/mutual society cannot charge you a higher premium than the one charged to people who are not ill or disabled.