Skip to main content

Why you must vaccinate your kids

By Aaron Carroll
July 9, 2014 -- Updated 2107 GMT (0507 HKT)
STORY HIGHLIGHTS
  • In the last few years, measles and mumps have been on the rise
  • Aaron Carroll: Immunizations can prevent contagious vaccine-preventable illnesses
  • He says people who refuse to vaccinate their children put other children in danger
  • Carroll: Widespread vaccination prevents disease outbreaks, this protects everyone

Editor's note:

(CNN) -- Although vaccines are required for entry into school in most places in the United States, the government does allow for exceptions, like religious reasons.

In the last few years, the rates of vaccine-preventable illness such as measles and mumps have been on the rise. In most cases, these outbreaks began with children who were unvaccinated. In a school environment, an unvaccinated child who has a contagious disease can more easily spread it to other children.

Aaron Carroll
Aaron Carroll

To combat this threat, some schools in New York have been refusing to allow unvaccinated children to attend school, where they might start outbreaks or make outbreaks worse. Several parents thought this was unfair and filed lawsuits. Just recently, though, a federal court ruled in favor of the city schools, citing that government has the power to make decisions that would protect public health.

The court made the right decision. Immunizations are important because they allow us to protect those who cannot protect themselves.

Review: Childhood vaccines are safe
Doctor: You can't get flu from flu vaccine
Experts: vaccines are necessary

Vaccines significantly decrease your risk of getting a disease if you come into contact with it, though there is still a tiny chance that you can get sick. When measles outbreaks occur, for example, more of the people who get sick tend to be unvaccinated, but some who are vaccinated can become ill.

Vaccine policy depends not only on the added protection that vaccines confer upon those who get shots, but also on the decreased likelihood that anyone will come into contact with the disease. This is known as herd immunity. It refers to the fact that when enough people are immunized, then there really can't be an outbreak. And if there can't be an outbreak, then everyone is protected, even those who can't get vaccinated.

This is critical, because there are people who are at increased risk for communicable diseases but cannot be given immunizations for various reasons. Small babies are susceptible to certain diseases, but can't be given all vaccines. The elderly sometimes have less-well functioning immune systems, and are at higher risk for diseases. The same goes for all immune-compromised patients, who are always under threat of infection.

We don't just get vaccines to protect ourselves. We don't just give them to our children to protect them. We do this so that all those other people are protected as well.

In 1995, the varicella vaccine, or the chicken pox vaccine, was introduced in the United States. Over time, more and more children received it. In 2011, a study was published in the journal Pediatrics that looked at how the program affected the number of children who died from the disease.

The first thing noted in the paper was that death from chicken pox went down significantly from before the vaccine was released. From 2001 through 2007, the rates of death remained much lower, with just a few children dying from chicken pox nationally each year.

What's notable is that from 2004 through 2007, not one child less than 1 year of age died in the United States from chicken pox. None. This is remarkable, because we cannot give the varicella vaccine to babies. It's only approved for children 1 year or older.

In other words, all those babies were saved not because we vaccinated them against this illness. They were saved because older children were. Enough of the older kids were vaccinated to grant herd immunity that protected babies from getting sick.

Widespread vaccination prevents disease outbreaks. This protects all people from getting ill.

But if some parents want their children to remain at risk by leaving them unimmunized, and those children get sick, the state has then to take steps to prevent outbreaks from occurring. In New York, one of the few children who developed measles earlier this year was an unvaccinated child. The state refused to allow that child's sibling, who was also unvaccinated, to go to school. That child also developed measles. The school maintains -- and it's hard to dispute -- that letting the second child go to school would have put everyone at higher risk.

People who refuse to vaccinate themselves, or their children, aren't just putting themselves at risk -- they're putting everyone else in danger, too.

Childhood vaccines are safe. Seriously.

Forgotten vials of smallpox virus found

Read CNNOpinion's new Flipboard magazine

Follow us on Twitter @CNNOpinion.

Join us on Facebook.com/CNNOpinion.

Part of complete coverage on
September 20, 2014 -- Updated 1624 GMT (0024 HKT)
John Sutter boarded a leaky oyster boat in Connecticut with a captain who can't swim as he set off to get world leaders to act on climate change
September 19, 2014 -- Updated 2322 GMT (0722 HKT)
Is ballet dying? CNN spoke with Isabella Boylston, a principal dancer at the American Ballet Theatre, about the future of the art form.
September 19, 2014 -- Updated 2147 GMT (0547 HKT)
Sally Kohn says it's time we take climate change as seriously as we do warfare in the Middle East
September 19, 2014 -- Updated 1302 GMT (2102 HKT)
Dean Obeidallah says an Oklahoma state representative's hateful remarks were rightfully condemned by religious leaders..
September 19, 2014 -- Updated 1922 GMT (0322 HKT)
No matter how much planning has gone into U.S. military plans to counter the Islamic State in Iraq and Syria, the Arab public isn't convinced that anything will change, says Geneive Abdo
September 19, 2014 -- Updated 1544 GMT (2344 HKT)
President Obama's strategy for destroying ISIS seems to depend on a volley of air strikes. That won't be enough, says Haider Mullick.
September 19, 2014 -- Updated 1303 GMT (2103 HKT)
Paul Begala says Hillary Clinton has plenty of good reasons not to jump into the 2016 race now
September 19, 2014 -- Updated 1501 GMT (2301 HKT)
Scotland decided to trust its 16-year-olds to vote in the biggest question in its history. Americans, in contrast, don't even trust theirs to help pick the county sheriff. Who's right?
September 19, 2014 -- Updated 0157 GMT (0957 HKT)
Ruben Navarrette says spanking is an acceptable form of disciplining a child, as long as you follow the rules.
September 19, 2014 -- Updated 1547 GMT (2347 HKT)
Frida Ghitis says the foiled Australian plot shows ISIS is working diligently to taunt the U.S. and its allies.
September 19, 2014 -- Updated 1958 GMT (0358 HKT)
Young U.S. voters by and large just do not see the midterm elections offering legitimate choices because, in their eyes, Congress has proven to be largely ineffectual, and worse uncaring, argues John Della Volpe
September 19, 2014 -- Updated 0158 GMT (0958 HKT)
Steven Holmes says spanking, a practice that is ingrained in our culture, accomplishes nothing positive and causes harm.
September 18, 2014 -- Updated 1831 GMT (0231 HKT)
Sally Kohn says America tried "Cowboy Adventurism" as a foreign policy strategy; it failed. So why try it again?
September 18, 2014 -- Updated 1427 GMT (2227 HKT)
Van Jones says the video of John Crawford III, who was shot by a police officer in Walmart, should be released.
September 18, 2014 -- Updated 1448 GMT (2248 HKT)
NASA will need to embrace new entrants and promote a lot more competition in future, argues Newt Gingrich.
September 16, 2014 -- Updated 2315 GMT (0715 HKT)
If U.S. wants to see real change in Iraq and Syria, it will have to empower moderate forces, says Fouad Siniora.
September 18, 2014 -- Updated 0034 GMT (0834 HKT)
Mark O'Mara says there are basic rules to follow when interacting with law enforcement: respect their authority.
September 16, 2014 -- Updated 1305 GMT (2105 HKT)
LZ Granderson says Congress has rebuked the NFL on domestic violence issue, but why not a federal judge?
September 16, 2014 -- Updated 1149 GMT (1949 HKT)
Mel Robbins says the only person you can legally hit in the United States is a child. That's wrong.
September 15, 2014 -- Updated 1723 GMT (0123 HKT)
Eric Liu says seeing many friends fight so hard for same-sex marriage rights made him appreciate marriage.
ADVERTISEMENT