Last month, Mayor Bill de Blasio declared a public health emergency in New York City in response to a measles outbreak that has sickened hundreds in ultra-Orthodox Jewish communities since last fall. His requirement that unvaccinated individuals in Williamsburg and Borough Park, Brooklyn submit to mandatory vaccinations or face possible fines brought to light the tension between civil liberties and community welfare that underlies the basic principles of public health.
As I wrote here several years ago, vaccines have easily been one of the major public health successes of the twentieth century, especially for the childhood diseases that were once leading causes of mortality. Instead of dying from diphtheria or rubella, we’re now vaccinated against them. Other illnesses such as polio and chicken pox that are not necessarily fatal but could cause lifelong complications are now avoidable with a series of immunizations.
Yet despite these victories, rates of vaccine-preventable diseases, notably measles, continue to rise. According to the Centers for Disease Control, there were 75 new cases of measles across the country last week, for a total of 839 cases so far this year, already double the entire number for 2018.
When a measles outbreak hit California in late 2014 and early 2015, the state responded by tightening its restrictions. At the time, it allowed parents to opt out of vaccines for personal reasons; now, it allows exemptions only for medical reasons. States that allow fewer exemptions generally experience fewer outbreaks. In Oregon, for example, which has been affected this season by an ongoing measles outbreak next door in Clark County, Washington, parents are still permitted to decline vaccinations for philosophical reasons; they can self-certify their status as objectors by watching a video module online and printing out and signing a form.
Although numerous studies have debunked any link between vaccines and autism, including one in Denmark published this spring, vaccine hesitancy remains so alarming that the World Health Organization declared it one of the top ten threats to global health in 2019, along with climate change, antimicrobial resistance, and weak primary health care. Parents in the United States who resist vaccinations are not necessarily uneducated or ill-informed; more often, they’re getting their information from a set of sources that confirm what they’re already likely to believe. In ultra-Orthodox neighborhoods in New York City and surrounding counties, anti-vaccination handbooks and pamphlets have been circulating and spreading misinformation within the insular community. In Oregon and Washington, middle-class parents who distrust big pharma and chafe against governmental interference are likely to encounter in their communities like-minded peers who reinforce their views.
One of the obstacles in overcoming to vaccine hesitancy is the inherent difficulty of proving a negative. Scientists will state a lack of correlation between vaccines and adverse health consequences, but for methodological reasons won’t claim that the former never causes the latter. To parents who resist vaccinations because of (discredited) fears of autism, the danger lies in the risk of triggering the disorder. This risk, in its uncertainty and unknowability, is more frightening than the disease against which the vaccine is designed to protect.
Several months ago, I was chatting with a recently married young woman, who told me that she and her husband weren’t sure they would vaccinate their children when the time came. They both, she said, personally knew of kids who were never the same after receiving childhood immunizations, whose personalities changed from outgoing and sociable to withdrawn and introverted. I trotted out the standard scientific and public health arguments in favor of vaccination, but she remained unmoved. It reminded me of the challenge of arguing against the evidence of personal experience, of trying to convince someone that what he or she has witnessed firsthand might be unreliable. It’s hard to argue a contrary position when the cause-and-effect seems so convincing. And how certain can one really be that the former didn’t result in the latter? Such are the complexities of countering vaccine hesitancy.
The battle against vaccine hesitancy will necessarily be multifaceted, and must include broad educational campaigns as well as one-on-one outreach. But governmental mandates play an important role, as well. We enjoy many rights in this society, allowing us to live, speak and assemble with a great deal of freedom. The right to endanger others with a dangerous and easily preventable disease should not be among them.