President-elect Donald Trump met Tuesday with Robert Kennedy Jr., an environmental activist (and Democratic political scion) who opposes mandatory vaccination laws because he believes in discredited conspiracy theories that immunizations are dangerous. Kennedy told reporters that Trump had asked him to lead a commission on vaccines.
Though Trump transition aides later said that the decision wasn’t final, the meeting was alarming to doctors, epidemiologists and public health experts such as myself. Kennedy is neither a physician nor a scientist; he has been at the forefront of pushing bogus assertions that vaccines cause autism — they do not — and he has compared side effects of immunizations to the Holocaust.
Which makes Tuesday’s encounter just the latest indication that the next president might be willing to discard science and medical research on vaccination in favor of debunked myths. There’s a real risk that Trump could politicize vaccines, undermining trust in one of the great public health interventions in human history.
Success of immunization programs in the United States should not be taken for granted. It took decades of hard work by doctors, the Centers for Disease Control and Prevention and state and local health departments to get vaccination rates to where they are today — over 90 percent for vaccines against polio, hepatitis B, chickenpox, measles, mumps and rubella.
The modern era of immunization programs began in the early 1960s when President John F. Kennedy, Robert Kennedy Jr.’s uncle, signed into law the Vaccination Assistance Act. This law allowed the CDC to support health departments in immunization-related activities.
In the late 1960s, after several measles outbreaks, there was a push for state laws requiring children to be vaccinated before starting school. By the early 1980s, all states had mandatory immunization laws in place (although until recently, all but two states allowed exemptions for religious or “philosophical” reasons). Over the decades, with bipartisan support, there was an expansion of federal funding for vaccines.
These efforts led to a gradual increase in vaccination rates among American children. But outbreaks of measles between 1989 and 1991 demonstrated that vaccination rates varied by population, and the vaccine delivery system required an overhaul. In 1991, President George H.W. Bush announced support for achieving immunization levels of 90 percent or more for children under 2 years old. That effort received a major boost from the Clinton administration’s Childhood Immunization Initiative and the Vaccines for Children Program. By 2001, the 90 percent vaccination rate target was achieved for most of the recommended vaccines.
Since the late 1990s, though, there has been a countervailing trend of increasing vaccine refusal. The relatively low state-level vaccine refusal rates are masked by substantial local clustering of vaccine refusers — who provide the tinder for outbreaks to start and spread like wildfire.
Until now, vaccines have enjoyed broad and bipartisan support. However, despite Kennedy’s family and political lineage, Trump’s involvement in this issue is likely to politicize the public discussion around vaccines.
And if vaccination becomes an idea closely associated with political identity, the high vaccination rates required to maintain what experts call “herd immunity” might be at risk. Herd immunity is indirect protection from infections when a large percentage of a population is vaccinated, decreasing the likelihood that an unvaccinated person will encounter someone who is infected.
Vaccines require broad public support to prevent outbreaks. And that support will certainly be undermined if it becomes undesirable for Republicans, or even only for the approximately 43 percent of the public that current polling shows approves of Trump. While herd immunity thresholds (i.e., what percentage of population needs to be vaccinated to prevent outbreaks) vary by disease and population, they range from 75 percent to 95 percent for most common childhood vaccine preventable diseases.
Political polarization influences the basic facts voters believe, research and polling have found. Just look at climate change: One survey last fall found that only 16 percent of conservative Republicans accept that virtually all the scientists who study the issue agree that human activity is mostly responsible for changing climate. So if Trump continues to push unwarranted skepticism about immunizations, real damage could result.
Experience in other countries suggests that vaccine confidence can decrease precipitously once challenged, and it takes time and substantial effort to get the public back on board. In the most notorious example, vaccination rates in Britain declined after a 1998 article in the journal Lancet pushed the purported link between the measles vaccine and autism. The measles vaccination rate, approximately 92 percent in the year before the 1998 paper, declined to a low of 80 percent by 2003 in England and Scotland. It took until 2011 for immunization rates to return to their earlier levels. The article was eventually retracted and found to be fraudulent, and its lead author lost his medical license.
In another case, after a scare regarding side effects of whooping cough vaccine in 1974, the vaccination rate for whooping cough in England and Wales dropped from over 80 percent in 1974 to a low of 31 percent in 1977 and 1978. Despite efforts by public health authorities, the vaccination rates did not reach the pre-1974 levels until 1988.
Here in the United States, my research has shown that vaccine refusal is associated with outbreaks of preventable disease such as measles and whooping cough. In fact, the Disneyland measles outbreak in 2015 was substantially attributed to vaccine refusal.
The United States has one of the strongest vaccine safety monitoring systems in the world. Safety is evaluated in clinical trials before a vaccine is approved by the FDA. Even after approval, scientists continue to monitor safety of vaccines using large-linked databases - the largest of which contained information for 178 million individuals by 2014.
Information gathered by these monitoring systems is published in peer-reviewed journals. The overall evidence base is periodically compiled and evaluated by independent scientific bodies. The most credible of such bodies is the National Academy of Medicine (a part of the National Academies of Sciences, which was created in 1863 by a congressional charter approved by President Abraham Lincoln). The National Academy of Medicine has conducted several reviews of vaccine safety, all of which have supported the continued use of vaccines. Notably, the reviews were conducted by highly qualified physicians and scientists — not politically appointed activists.
Due to the overwhelming evidence backing their safety, doctors and scientists strongly support vaccines. The American Academy of Pediatrics, American Medical Association and Infectious Diseases Society of America not only support immunization, in general, but they also endorse adhering to the vaccine schedule recommended by the Centers for Disease Control and Prevention.
Trump, however, has challenged that schedule, saying in a 2015 debate that he wanted “smaller doses over a longer period of time.” Worse, a few years before that, he repeated the false claim that vaccination was causing autism.
Still, perhaps there is one area where scientists and the next administration can find common ground: investment in vaccine safety research. Most vaccine proponents are also big supporters of vaccine safety research. While the CDC, the Food and Drug Administration and — to some extent — the National Institutes of Health have been conducting rigorous vaccine safety research, the introduction of new vaccines requires further expansion of safety surveillance conducted, evaluated and synthesized by physicians and scientists. More money would help that effort.
Vaccines are one of the most successful advances in public health of all time. Among American children born between 1994 and 2013, 322 million cases of illnesses and 732,000 deaths will be prevented by vaccines over their lifetime. Threats to vaccine confidence can result in a large number of avoidable illnesses and even loss of life.
Elections have consequences, the saying goes. It would be awful if one consequence of the last one was potentially thousands of preventable childhood deaths.
Omer is the William H. Foege chair in global health and a professor of global health, epidemiology and pediatrics at Emory University.