Here are some of the most common arguments for and against vaccination. (The Washington Post)

In Iowa yesterday, GOP presidential hopeful Carly Fiorina said that parents shouldn't be required to vaccinate their kids. The Post's Jenna Johnson reports:

"When in doubt, it is always the parent's choice," Fiorina said during a town hall in an agricultural building in rural Iowa on Thursday evening. "When in doubt, it must always be the parent's choice."

Fiorina recounted how her daughter was "bullied" by a school nurse when deciding whether to give her own child the HPV vaccine. Later, Fiorina clarified her statements for a group of reporters. "When you have highly communicable diseases where we have a vaccine that's proven, like measles or mumps, then I think a parent can make that choice -- but then I think a school district is well within their rights to say: 'I'm sorry, your child cannot then attend public school.' So a parent has to make that trade-off."

Fiorina said that while "highly communicable diseases" are one thing, schools should not be able to mandate "these more esoteric immunizations." She also took issue with California's recent decision to abolish the state's personal belief exemption to vaccine mandates, saying "California is wrong on most everything, honestly."

Fiorina is treading on thin ice here, from both a political standpoint and a public health one. Politically speaking, more than two-thirds of the general public say that all children should be required to be vaccinated, according to a February Pew Research Center poll. And even among the Republican voters Fiorina's trying to reach, 64 percent say vaccines should be mandatory, compared to only 34 percent who say parents should decide. It's hard to see what advantage she hopes to gain from staking out a minority position within her own party.

More importantly though, her position runs contrary to the prevailing opinion in science and public health. As a reminder, here's a chart on the resurgence of measles in 2014 that shows what happens when you let parents decide whether to vaccinate their kids:


The vaccine skepticism boom of the 2000s, fueled by thoroughly debunked notions of a link between vaccines and autism, contributed to a measles vaccination rate in the U.S. -- 91 percent -- that's now among the lowest in the developed world, and lower than places like Angola, Zimbabwe and Bangladesh, according to the World Bank. That low vaccination rate made possible the explosion of measles cases last year.

Of course, vaccine skeptics counter that measles is rarely fatal. If a parent decides not to vaccinate their kids, they're not putting anyone at serious risk. Right?

Wrong. Try telling that to the family of a Washington woman who died from measles this spring, the first such death in the United States in a dozen years. She was in a hospital receiving treatment for other conditions, and was on immunosuppressant drugs. She was exposed to measles when another patient infected with the disease came into the hospital.

Public health officials didn't release the woman's name for privacy reasons, but they did say that she wasn't elderly. In other words, her death may have been prevented if our vaccination rates were similar to what you see elsewhere in the wealthy world.

Carly Fiorina appears to be trying to have it both ways on the vaccine question -- she tells supporters in Iowa that parents should have the final say, and then tells reporters that schools should be able to refuse admission to kids who haven't been vaccinated. But as the story out of Washington shows, decisions to not vaccinate affect far more people in a community than just parents and their kids.

Beyond that, Fiorina's parsing of vaccine-preventable diseases into "highly communicable" and "more esoteric" ones is at odds with considered opinion. With the possible exception of tetanus, every disease in the CDC's recommended schedule of immunizations is communicable between humans, many highly so.

The science on vaccines is settled -- the public health benefits of a robust vaccine schedule vastly outweigh the minor risks. And given that most of the public agrees with this, Fiorna's play for a relatively small group of vaccine-skeptical voters is puzzling.