The chance that a child will have a severe reaction to the MMR vaccine is less than the chance they will die in 200 mile car ride

Backstory: Several weeks ago Newsday refused to publish a comment I posted on the article “Vaccine court protects ‘big pharma‘”. Having experienced this before (they have a very limited window to submit comments), I decided to rewrite the comment and submit it as an editorial. Recently I discovered it had been published. Unfortunately, the editor removed one of the key points from my piece, and also botched the grammar on the third line, so I am republishing the full piece here, with minor copyediting.

The recent editorial “Vaccine court protects ‘big pharma’” represents a severe distortion of vaccines and the risks associated with them. It is true that vaccines can cause serious side effects and that such side effects are listed on the CDC’s website. What the author neglects to mention is the extreme rarity of these side effects, which is also clearly stated on the same website. The chance that a child will have a severe allergic reaction or encephalitis from the MMR vaccine is about 1 in 1 million. To put this in perspective, this is less than the chance that a student will die from a school shooting during all of their K-12 their school years. Parents continue to send their kids to school, however, because the benefits associated with an education greatly outweigh the tiny risk that their child might die. As another example, a 1 in 1 million risk is less than the risk of dying in a 200 mile car ride in the state of California. Parents continue to drive their children around, however, because the benefits of transportation greatly outweigh the risks associated with. The same principle holds true with vaccines – the benefits of being immunized from life-threatening diseases greatly outweighs the tiny risk of a serious side effect.

One should also consider the risks that compound when children are not vaccinated. Consider that in 2013 alone, 145,700 people died worldwide from measles, while in the United States, where vaccinations are now common, zero people died that same year. In 1962, the year that the first measles vaccine was introduced, it was estimated that 90% of people in the US would develop measles by the age of 15. Among the millions that would develop measles each year, an average of 150,000 patients would have respiratory complications and 450 would die each year. Over the intervening decades, measles has been virtually eliminated from the US precisely because of vaccination.  A similar story holds for many other life threatening diseases, most notably smallpox, diphtheria, pertussis, and polio.  Experts estimate that in the years from 1994-2013, vaccination has prevented 732,000 deaths in the United States and saved the economy $1.38 trillion.

The author of the editorial is also correct that vaccines are not 100% effective, because people’s immune systems vary greatly and sometimes a person may not develop the correct antibodies (for MMR, this happens about 1-5% of the time). Therefore, there is a small chance that a person who was vaccinated can still develop the disease and transfer it to others. However, if enough other people are vaccinated, the chances that that person will get that disease to begin with are extremely low.

We do not have to place ‘blind trust’ in big companies as the author suggests. All vaccines must past through years of rigorous safety testing at the FDA before they can appear on the market (on average this process takes 10-15 years). Once on the market, the FDA and other agencies continue to monitor the safety of vaccines. We also have a very powerful tort system which many argue gives excessive power to the plaintiff. The statistics compiled by research agencies across the world paint an extremely clear picture – vaccines work and the benefits of vaccination greatly outweigh the tiny risks of a side effect.

Addendum: After publication of this, some people have suggested to me that the analogy to school shootings may make vaccines seem more threatening, since many parents are very concerned about the safety of their children at school. This is a valid point, so one should be careful before drawing the connection, because just as many people perceive the threat of vaccines to be much higher than it is, the same goes for school shootings. People overestimate certain risks (like shark attacks, etc) that seem scary while ignoring much larger risks that are more mundane (like dying by falling down stairs). The average person’s perception of risk is always going to be very skewed. Therefore there are likely much better analogies to help the average person relate to what a risk of 1 in 1 million is. For example, the chance of dying on a 150 mile car trip in California is about 1 in 1 million (source)
Here are some things that are a lot more likely: (source)
— Dying next year in a car accident (1 in 17,625)

— Dying next year from poisoning (1 in 86,313)
— Dying next year in a fire (1 in 87,500)

The other point that should be made is that in the rare case that a child has a severe symptom after a vaccine, this does not imply the vaccine was at fault. The entire topic of severe vaccine reactions is poorly documented due to the extreme rarity of the event, which makes it hard to study. The statistics that are available are basically just based on anecdotal accounts of a child having a severe symptom concurrent with a vaccination. Therefore, the statistic at 1 in 1 million should be considered an upper bound (or in other words, an overestimate of the rate). There are good reasons to believe the actual risk is much smaller. However, I didn’t want to wade into a debate about what the exact best value is for the risk, since such debates usually can become quite intricate and distract from the point I was trying to make.

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