MR and MMR vaccines used to create seropositiveness for measles antibodies in my opinion is no protection against measles even in vaccinated areas above the threshold to supposed herd immunity. Measles vaccines are complete nonsense and a waste of public money and health as they contain toxins.
China has one of the most vaccination compliant populations in the world. In fact, measles vaccine is mandatory. So why have they had over 700 measles outbreaks from 2009 and 2012 alone? The obvious answer is the measles vaccines are simply NOT effective.