(Los Angeles Times) – California parents are deciding against vaccinating their kindergarten-age children at twice the rate they did seven years ago, a fact public health experts said is contributing to the reemergence of measles across the state and may lead to outbreaks of other serious diseases.
The percentage of kindergartens in which at least 8% of students are not fully vaccinated because of personal beliefs has more than doubled as well, according to data on file with the state. That threshold is significant because communities must be immunized at a high rate to avoid widespread disease outbreaks. It is a concept known as herd immunity, and for measles and whooping cough at least 92% of kids need to be immune, experts say.
High vaccination levels in the U.S. have helped millions of children avoid serious diseases and saved tens of thousands a year from paralysis, birth defects and death, experts say. But the risk of infectious disease remains a concern. Recent measles cases, for example, were brought into the country by travelers and quickly spread to several unvaccinated individuals.
“Five days a week, [children are] in their small classroom,” said Shannon Stokley, an epidemiologist at the National Center for Immunization and Respiratory Diseases, part of the Centers for Disease Control and Prevention. “That’s the perfect conditions for spreading germs and spreading infections.”