Measles outbreak in U.S. started by unvaccinated child.

The measles outbreak that started in San Diego was imported by an unvaccinated 7 year old boy who visited Switzerland. The MMWR early release report is here. There have been at least 11 secondary cases, and a large-scale public health response has been required to deal with the many contacts of this child who are also unvaccinated because their parents used "personal beliefs exemptions." How many of these does it take before we do away with these ridiculous exemptions? Parents who refuse vaccines not only put their own children at risk, but also risk the lives of children who have to rely on herd immunity for protection (immunocompromised children who cannot receive the live-attenuated measles vaccine and those too young to be vaccinated).