How Vaccine Resistance Rose in U.S.
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, which in 2000 was designated by the World Health Organization as a country that has eliminated measles, has seen a rise in outbreaks. The W.H.O. has listed vaccine hesitancy as one of the top threats to global health.
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 their anti-vaccination statements; and more recently, 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.”
It remains true that the overwhelming majority of American parents have their children vaccinated. Parent-driven groups like Voices for Vaccines, formed to counter anti-vaccination sentiment, have proliferated. Five states have eliminated exemptions from school vaccine requirements, permitting only medical opt-outs.
But there are ominous trends. For highly contagious diseases like 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 percent. The Centers for Disease Control and Prevention found that the vaccination rate for the measles, mumps and rubella (M.M.R.) injection in kindergartners in the 2017-2018 school year had slipped nationally to 94.3 percent, the third year in a row it dropped. Almost
More cases of diseases that had disappeared.
all states have at least one anti-vaccine group.
Public health experts say that patients and many doctors may not appreciate the severity of diseases that immunizations have thwarted, like polio, 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.”
The growth of vaccine doubt in America coincides with several competing forces and attitudes. Since the early 2000s, as the number of required childhood vaccines was increasing, a generation of parents was becoming hypervigilant about their children and, through social media, being validated for doing so. In their view, parents who permitted vaccination were gullible.
In 2011, Dana Fuqua, of Aurora, Colorado, pregnant with her first child, felt the pull of groupthink parenting.
She had just moved to the area, so she reached out to mothers’ groups on Facebook. Colorado has a strong vaccine-resistant movement. Ms. Fuqua’s new friends urged her to have a drug-free birth and never to let a drop of formula pass her baby’s lips. Vaccines, it followed, were anathema.
The women intimidated her. “I didn’t argue with them,” Ms. Fuqua said. “I was so desperate for their support that I compromised by delaying the vaccine schedule.”
But when her second child was born prematurely, susceptible to illness, the group’s approval was not as important as her baby’s safety. Her position shifted, and she had both children fully vaccinated.
There have been anti-vaccination movements at least since 1796. But many experts say that the current one can be traced to 1982, when NBCTV aired a documentary that took up a controversy 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 criticized the show as dangerously inaccurate. But fear spread. Anti-vaccination groups formed.
Then, in 1998, Andrew Wakefield, a British gastroenterologist, published a Lancet study (since discredited and withdrawn), associating the M.M.R. vaccine with autism.
Faced with risking autism or measles, some parents thought the answer was obvious. But 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.
People are flummoxed by numerical risk. “We pay more attention to numerators, such as ‘16 adverse events,’ than we do to denominators, such as ‘per million vaccine doses,’ ” Dr. Buttenheim said.
A concept called “ambiguity aversion” is also involved, she added. “Parents would like to be told that vaccines are 100 percent safe,” she said. “But that’s not a standard we hold any medical treatment to.”
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 in Maryland.
Nowhere is that reinforcement more clamorous than on social media, Dr. Limaye added. “You may only see your pediatrician a few times a year, but you can spend all day on the internet,” she said.
People also tend to believe an individual’s anecdotal narrative over abstract numbers. When Jenny McCarthy, an actress, insisted that vaccines caused her son’s autism, thousands found her to be more persuasive than data showing otherwise. A nascent movement took hold.
As of 2014, studies showed that parental confidence in public health authorities and in pediatricians was dropping. 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.
Soon, shared decision-making became the model of doctor-patient engagement. Pediatricians offered to stagger vaccine schedules. Some were even flexible about vaccinations altogether.
Shortly after Emma Wagner had given birth in Georgia, a pediatrician on the hospital ward examined the baby.
“He asked me if I was interested in the hepatitis B vaccine,” she said of an inoculation typically done at birth. She was apprehensive.
“I was motivated by fear,” Ms. Wagner said. “I thought, ‘Until I know for certain that these are safe, I won’t do it.’ The pediatrician said, ‘I will support your decision and in a few years we’ll talk about exemptions for school.’ ”
She has since become a supporter of immunization.
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.”
With so many different but deeply held convictions, public health experts struggle to design vaccine-positive campaigns. Dr. 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.
Experts say the best way to change the narrative is for medical professionals to educate parents and patients.
“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,” said Dr. Offit, the infectious disease specialist. “It’s time for us to stand back and explain ourselves better.”