One un-vaccinated child has led to a measles outbreak that has spread to seven states and to two other countries. Quite an accomplishment for a child who just wanted to go see Mickey Mouse at Disneyland in California. That’s all it takes: one un-vaccinated person and an exposure to a virus, and viola!, you’ve got an outbreak.
Many people are not having their children vaccinated against common childhood diseases, such as measles, and rely on ‘herd immunity’ to protect their child from contacting a communicable disease. In order for herd immunity to work, 96% to 99% of the people around that un-vaccinated child must have either taken vaccinations or had the particular disease in the past. Because the anti-vaxxer movement has been around for over a generation now, we have both adults and children who have never been vaccinated and never been exposed to childhood diseases.
The math the experts did revealed that only 50% to 86% of the people at Disneyland that infamous day had been immunized or had the measles in the past stated Dr Jennifer Walden. Herd immunity doesn’t work when the numbers are so low. Since these numbers would also apply to any given location on any given day, experts are surprised that measles (and other diseases) don’t break out more often.