To understand the seriousness of the discussion:
June 1999. A religiously affiliated school in the Netherlands had a large measles outbreak, 160 cases of measles of school students.
Total cases of measles were 2961.
510 patients were hospitalized.
3 died as a result of the measles.
95% of affected patients were unvaccinated,
5% were vaccinated, with 80% (of the 5%) having received just the initial MMR shot, the rest were unknown if they have received a second shot or not.
This demonstrates the seriousness of the measles virus.