A new study that looks at recent outbreaks of measles and pertussis (otherwise known was whooping cough) suggests what many people have suspected all along: Many of them occur in areas where large numbers of people are unvaccinated on purpose.
Vaccine “refusal” is a hot new trend sweeping the nation. The law doesn’t require parents to vaccinate their kids, but public schools generally won’t accept students who haven’t had certain shots, though many states allow exemptions for non-medical reasons. In the past, those exemptions were mostly taken by people with certain religious beliefs (like Christian Scientists), but in recent years, the numbers have risen, especially in states that allow “philosophical” exemptions in addition to religious ones. In California, for the 2013-2014 school year, for example, only 1,000 people were granted exemptions for medical reasons, whereas over 17,000 people took them for philosophical reasons, as reported by the Centers for Disease Control. A law passed in the state of California last year will take effect in July of this one which will no longer allow for the so-called “personal exemptions which have allowed so many to slip through unvaccinated, hurray.
The CDC noted in the report that the unvaccinated tend to cluster geographically, increasing the likelihood of outbreaks further. The new study, published in The Journal of the American Medical Association, examined 1,416 cases of measles and 32 pertussis outbreaks in the United States. Of the measles cases, 56.8 percent of the people who contracted the disease were unvaccinated, and of those, 70.6 percent were not vaccinated for non-medical reasons. Of the 12 pertussis outbreaks, 8 out of 12 had very high numbers — between 59 and 93 percent — of intentionally unvaccinated victims.
These findings are worth pondering at length, if you ever suspect you might need to make a vaccination decision for yourself or others. “The phenomenon,” the report concludes, “of vaccine refusal was associated with an increased risk for measles among people who refuse vaccines and among fully vaccinated individuals.” Remember: When you don’t vaccinate your kids, you’re putting other people’s children at risk, too.* In the case of whooping cough, “Although resurgence has been attributed to waning immunity and other factors, vaccine refusal was still associated with an increased risk for pertussis in some populations.”
*This posted has been corrected to reflect that, while a percentage of vaccinated adults are still at risk of measles, the majority are not.