The question is often whispered, the questioners sheepish. But increasingly, parents at the New York playground where Dr. Elizabeth A. Comen takes her young children have been asking her: “Do you vaccinate your kids?”
Dr. Comen, an oncologist who has treated patients for cancers related to the human papillomavirus that a vaccine can now prevent, replies emphatically: Absolutely.
She never imagined she would be getting such queries. Yet these playground exchanges are reflective of the national conversation at the end of the second decade of the 21st century – a time of stunning scientific and medical advances but also a time when the United States may, next month, lose its World Health Organization designation as a country that has eliminated measles, because of outbreaks this year. The WHO has listed vaccine hesitancy as one of the top threats to global health.
As millions of families face back-to-school medical requirements and forms this month, the contentiousness surrounding vaccines is heating up again, with possibly even more fervor.
Though the situation may seem improbable to some, anti-vaccine sentiment has been building for decades, a byproduct of an internet humming with rumor and misinformation; the backlash against Big Pharma; an infatuation with celebrities that gives special credence to the anti-immunization statements from actors such as Jenny McCarthy, Jim Carrey and Alicia Silverstone, rapper Kevin Gates and Robert F. Kennedy Jr.; and now, the Trump administration’s anti-science rhetoric.
“Science has become just another voice in the room,” said Dr. Paul A. Offit, an infectious disease expert at Children’s Hospital of Philadelphia. “It has lost its platform. Now, you simply declare your own truth.”
The constituents who make up the so-called vaccine resistant come from disparate groups, and include anti-government libertarians, apostles of the all-natural and parents who believe that doctors should not dictate medical decisions about children. Labelling resisters with one dismissive stereotype would be wrongheaded.
“To just say that these parents are ignorant or selfish is an easy trope,” said Jennifer Reich, a sociologist at the University of Colorado Denver, who studies vaccine-resistant families.
It remains true that the overwhelming majority of American parents have their children vaccinated. Parent-driven groups such as Voices for Vaccines, formed to counter anti-vaccination sentiment, have proliferated. Five states have eliminated exemptions for religious and philosophical reasons, permitting only medical opt-outs.
But there are ominous trends. For highly contagious diseases such as measles, the vaccine rate to achieve herd immunity – the term that describes the optimum rate for protecting an entire population – is typically thought to be 95 per cent. The Centers for Disease Control and Prevention found that the vaccination rate for the measles, mumps and rubella (MMR) injection in kindergartners in the 2017-18 school year had slipped nationally to 94.3 per cent, the third year in a row it dropped.
Seven states reported rates for the MMR vaccine that were far lower for kindergartners, including Kansas at 89.1 per cent; New Hampshire, 92.4 per cent; the District of Columbia, 81.3 per cent. (The highest is West Virginia at 98.4 per cent.)
Almost all states have at least one anti-vaccine group. At least four have registered political action committees, supporting candidates who favor less restrictive vaccine exemption policies.
Public-health experts say that patients and many doctors may not appreciate the severity of diseases that immunizations have thwarted, such as polio, which can affect the spinal cord and brain – because they probably have not seen cases.
“Vaccines are a victim of their own success,” said Dr. Offit, a co-inventor of a vaccine for rotavirus, which can cause severe diarrhea in young children. “We have largely eliminated the memory of many diseases.”
There have been anti-vaccination movements at least since 1796, when Edward Jenner invented the smallpox vaccine. But many experts say that the current one can be traced to 1982, when NBC aired a documentary, DPT: Vaccine Roulette, that took up a controversy percolating in England: a purported tie between the vaccine for pertussis – a potentially fatal disease that can cause lung problems – and seizures in young children.
Doctors sharply criticized the show as dangerously inaccurate. But fear spread. Anti-vaccination groups formed. Many companies stopped making vaccines, which were considered loss-leaders and not worth the corporate headache.
Then, in 1998, Andrew Wakefield, a British gastroenterologist, published a Lancet study (since discredited and withdrawn), associating the MMR vaccine with autism.
Faced with risking autism or measles, some parents thought the answer was obvious. Most had never seen measles, mumps or rubella because vaccines had nearly eliminated them. But they believed they knew autism.
And most people are notoriously poor at assessing risk, say experts in medical decision-making.
Many stumble on omission bias: “We would rather not do something and have something bad happen, than do something and have something bad happen,” explained Alison M. Buttenheim, an associate professor of nursing and health policy at the University of Pennsylvania School of Nursing.
Relatively few people are absolutists about refusing all vaccines. “But if you’re uncertain about a decision, you’ll find those who confirm your bias and cement what you think,” said Rupali J. Limaye, a social scientist who studies vaccine behaviors at the Johns Hopkins Bloomberg School of Public Health.
Nowhere is that reinforcement more clamorous than on social media, Ms. Limaye added. “You may only see your pediatrician a few times a year, but you can spend all day on the internet,” she said.
The primary reason for healthy people to get the flu shot is to protect those with compromised immune systems, like infants and older adults, from getting sick. But altruism isn’t a great motivator for parents, Prof. Buttenheim said. “They are much more concerned about protecting their own child at all costs,” she said.
Contrast that attitude with the collective goodwill of the 1950s, say medical sociologists, when American parents who had seen President Franklin D. Roosevelt’s wheelchair as a debilitating symbol of polio patriotically sought to vaccinate their children to help eradicate the disease worldwide.
By 2014, studies showed that parental confidence in authorities such as the CDC and in pediatricians was dropping, especially around vaccines. Mistrust of Big Pharma was even more pronounced.
By then, Donald Trump was offering support on Twitter for the discredited link between autism and vaccination. As president-elect, he met with leaders of the anti-vaccination movement, although as measles cases surged, he endorsed vaccination.
As parenting became rife with orthodoxy, the Marcus Welby model of the paternalistic doctor retreated. Patients asserted autonomy, brandishing internet printouts at doctors. Shared decision-making became the model of doctor-patient engagement.
Pediatricians offered to stagger vaccine schedules. Some were even flexible about vaccinations altogether.
Libertarianism also courses through vaccine hesitation, with parents who assert that government should not be able to tell them what to put in their bodies – a position often marketed as “the right to choose.”
“Having the government order them to do something reinforces conspiracy theories,” said Daniel Salmon, director of the Institute for Vaccine Safety at Johns Hopkins. “And people perceive their risk to be higher when it’s not voluntary.”
In reality, he said, one’s risk of harm is greater while driving to an airport than it is being on the airplane itself. But driving is voluntary and gives the illusion of control. People fear flying because they cannot control the plane. By extension, many childhood vaccines are not voluntary, which rattles those who prefer to believe they can control their health.
With so many different but deeply held convictions, public-health experts struggle to design vaccine-positive campaigns.
In 2017, researchers applied the six values of “the moral foundations theory” to vaccine attitudes, surveying 1,007 American parents.
The results were intriguing. Those most resistant to vaccines scored highest in two values: purity (“my body is a temple”) and liberty (“I want to make my child’s health-care decisions”).
A third, said Saad B. Omer, director of Yale’s Global Health Institute and an author of the study, was also telling: deference to authority – a score indicating whether one was likely to adhere to the advice of experts like a pediatrician or the CDC.
Mr. Salmon’s team at Johns Hopkins is working on an app to capture parents’ vaccine attitudes and to tailor information to persuade them to vaccinate their children.
Pediatricians are front-line persuaders, he said, and they should be compensated for the time it takes to educate parents.
Most experts note that physicians themselves, never mind parents, have no idea about the federal vaccine monitoring systems, which have been in place for more than 20 years.
“We ask parents in the first two years of their child’s life to protect them against 14 diseases, that most people don’t see, using fluids they don’t understand,” Dr. Offit said. “It’s time for us to stand back and explain ourselves better.”
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