We don'tow do you know that in 30 years time it won’t become apparent that the mmr is responsible for the huge increases in cancer rates all over the planet
But we do know now that measles can cause this:
oday – at the age of 18 – Maximilian is still with us. His condition has slowly, but steadily worsened over the years. He can no longer sit or hold his head up. After all those years in which he could at least be fed like a baby, his chewing and swallowing capabilities have lately ceased significantly. His body temperature regulation is unstable; he has many seizures, unpredictable, sometimes strong, sometimes barely noticeable. We feed him by a stomach tube and carry him around in his wheel chair. His level of reaction to his environment varies from little to none
https://www.vaccinestoday.eu/stories/how-measles-can-change-a-life/
There is plenty of research on the dangers of measles, it's your choice to decide you want to take that risk.
Luckily for you, most people are vaccinated, so with a vaccination rate of over 95% the risk of a measles epidemic is low. So you are protected by other people.