Over the last couple of months, Disney has (temporarily) stopped being famous for its princesses and has become infamous for the outbreak of measles that started at the theme park in December. Since then, the virus has spread to fourteen different states and Mexico.6
According to data provided by the CDC, 644 cases of measles were reported in 27 states in 2014. Last year, these cases constituted the largest measles outbreak since measles was eliminated in the US in 2000. In January alone, 102 confirmed cases of measles have been reported across these 14 states.4 At this rate, the incidence of measles in 2015 is set to surpass last year’s record.
The CDC has reported that most cases of measles have occurred in patients that have never been vaccinated, and the organization reminds the public that measles can be introduced into the U.S. population at any time by travelers.4
In response, White House Press Secretary Josh Earnest recently said, “people should evaluate this for themselves with a bias toward good science and toward the advice of our public health professionals.” In an interview with NBC news, President Obama recently stated that there are no reasons for parents to avoid vaccinating their children.2
The debate continues, with some concerned parents demanding that unvaccinated children be disallowed from classrooms.5 In contrast, parents that support the anti-vaccine movement reserve their right to avoid vaccinating their children.6
The mounting epidemic makes it difficult to defend such a position, however. In Santa Monica, California today, 14 infants were quarantined after a child less than 12 months of age had a confirmed case of measles.3 This child may have been too young to be vaccinated, but he or she should have been protected by herd immunity.
Herd immunity refers to the protection that an entire population benefits from against an infectious agent when a certain percentage of individuals are vaccinated. Since measles is so contagious,7 the CDC reports that 95% of the population must be vaccinated against measles for the protective effects of herd immunity.8 This threshold is not being reached, partly because of parents refusing to vaccinate their children.
Even with increasing national dialogue about vaccination and infectious disease, this debate is far from over.