Space & Innovation

The Presidential Politics of Vaccinations

Vaccination is widely accepted in medicine but remains controversial in presidential politics. Here's why.

In medicine the benefits of childhood vaccination are widely accepted. The evidence is clear and overwhelming: vaccines do not cause autism (or any other condition), and the benefits of preventing severe diseases far outweigh the small risks of side effects. This is non-controversial, and vaccination is a staple of preventive medicine worldwide.

In political circles, however, the topic has become an issue in the presidential race. Republican nominee Donald Trump has changed his position on vaccines, suggesting at different times that they are both dangerous and safe. In March 2014 he tweeted "Healthy young child goes to doctor, gets pumped with massive shot of many vaccines, doesn't feel good and changes - AUTISM. Many such cases!"

But a year later during a Republican debate said "I am totally in favor of vaccines, but I want smaller doses over a longer period of time."

RELATED: Vaccine Fears Not New - Here's Why

The following day the American Academy of Pediatrics issued a statement to "correct false statements made during the Republican presidential debate last night regarding vaccines. Claims that vaccines are linked to autism, or are unsafe when administered according to the recommended schedule, have been disproven by a robust body of medical literature. It is dangerous to public health to suggest otherwise...Vaccines work, plain and simple. Vaccines are one of the safest, most effective and most important medical innovations of our time."

Green Party candidate Jill Stein, who is a medical doctor, posted a July 31 tweet that "There's no evidence that autism is caused by vaccines," but within five minutes deleted that statement and replaced it with a somewhat more equivocal position: "I'm not aware of evidence linking autism with vaccines."

This subtle change did not go unnoticed; a writer for "Slate" expressed concern that "the Harvard-trained physician is catering to vaccine skeptics by engaging in a bit of double-speak. Stein acknowledges that vaccines have done enormous good for public health and says she supports them. But she simultaneously suggests that there may be unresolved 'questions' about their safety and makes broad claims that the American drug-approval process has been tainted by corporate influence.... Stein's latest vacillations on Twitter haven't helped the impression that she's trying to avoid alienating anti-vaxxers without outright bear-hugging them."

WATCH: The Future of Vaccines

For some candidates-especially those of a more liberal bent such as former New Mexico governor and Libertarian Party nominee Gary Johnson-the issue is complicated by the desire not to alienate voters who are concerned with civil liberties, specifically regarding mandatory childhood vaccinations.

Andrea Kitta, an Associate Professor at East Carolina University and author of "Vaccinations and Public Concern in History," explained in a DNews interview why vaccination is a political issue for many: "People who choose not to vaccinate truly believe their rights are being violated and believe they are in danger of further violation... Some people will now reject vaccines solely on the basis that they feel their rights are being violated-not because they necessarily oppose or are even uncertain about vaccination."

Complaints that mandatory vaccination infringe on personal rights is nothing new; a British Anti-Vaccination League was created in 1853.

When California Gov. Jerry Brown signed a law requiring all school-attending children to be vaccinated for public safety in 2015, it did not require childhood vaccinations for every child-only those enrolled in California public and private schools. Children who go to home-based private schools or are home-schooled are exempt. The rationale for mandatory vaccination of all schoolchildren (with rare health or religions exceptions) involves what's known as "herd immunity"-essentially that even a small number of unvaccinated people put others at risk.

RELATED: 5 Disease Outbreaks Linked to Vaccine-Shy Parents

Democratic nominee Hillary Clinton is the only candidate who has clearly and consistently come out in favor of vaccinations, tweeting: "The science is clear: The earth is round, the sky is blue, and #vaccineswork. Let's protect all our kids."

In the end, as "The Atlantic" notes, "Surveys reveal that the vast majority of Americans correctly understand vaccines to be safe. There simply aren't many votes to win by pandering to anti-vaxers. In a society of millions, though, the margins are large enough to drive thousands of votes-and maybe that's why some candidates continue to take less-than-firm stances on the safety of vaccines."