You’re as likely to be struck by lightning as to have a severe reaction to a vaccine.

I was reading an article in Time last week about parents not vaccinating their children. The story was about how this phenomenon is becoming more widespread.

These kinds of stories are weird to me because vaccines are pretty safe. The risk of an adverse side effect is incredibly small. For example, the risk for anaphylaxis from the Hepatitis B Virus vaccination is around 1 in 600,000. This is about the same risk as being struck by lightning (1 in 700,000).

Of course, the article wasn’t talking about known risks. Instead, it was referring to a hypothesized link between vaccines and autism.

People proposed this link when they noticed that cases of autism and the number of vaccinations were rising at the same time. Of course, just because two things happen to occur at the same time, this does not mean they are causally linked. For example, the increase in global temperature is not related to the decrease in the world’s populations of pirates (despite what the Pastafarians say).

So how could an increased number of vaccinations cause an increase in the number of cases of autism? I have seen two ideas put forth. The first is that thimerosal is to blame. The second is that there are so many vaccinations now that we are stressing out the body’s immune system. Most likely neither idea is valid.

Thimerosal is a mercury-based preservative that used to be used in vaccines. Even though there haven’t been any good studies on the effects of thimerosal on brain development, everyone knows mercury is bad for the brain. So the idea behind thimerosal makes some sense.

Back in 2001, vaccine manufacturers decided to eliminate thimerosal from their vaccines. We would predict, then, that cases of autism should go down significantly if thimerosal was linked to autism. They haven’t. In fact, in one California study, cases have continued to climb. So thimerosal is most likely not to blame.

Another point that has been made is that there are so many vaccines now that we are stressing out our bodies’ immune systems. Again, this concern is unfounded.

Vaccines are injections of viral proteins. Our bodies see the proteins and raise antibodies to them. Then when a virus invades, we have antibodies that recognize the virus and target it for destruction.

It is the number of viral proteins that matter in terms of taxing the body’s immune system and not the number of vaccinations. All of the current vaccines put together do not have as many viral proteins as the old smallpox vaccine (150 vs. 200). So the number of vaccines is unlikely to be the issue.

What all of this means is that vaccines are probably not responsible for the significant increase in the number of cases of autism. What is responsible? No one knows for sure.

It may be that the rise just comes from all of us recognizing the symptoms more. Or it could be due to some cause we don’t know about or understand.

What we do know is that vaccines save many lives. I assume no one wants to go back to the early 20th century when polio epidemics swept the country. For example, 2,500 cases of polio ended up at one Los Angeles hospital between May and November of 1934. And in 1952, the U.S. had 21,000 cases of paralytic polio.

We can prevent this sort of thing from happening by making sure everyone is vaccinated. And yet there are people who choose to hide behind the people who take the miniscule risk of getting vaccinated.

Is this a matter of free choice? Should parents be allowed to opt out of vaccinating their children even if it risks society at large?

One idea, I suppose, is to have people who choose not to be vaccinated to sign a waiver saying they accept full responsibility for their actions. In practice this would mean that health insurance and the government would not be responsible for their children’s health care bills if they become ill with one of the diseases they refused to be vaccinated against.

And if your infant, grandma, or immuno-suppressed cousin came down with a disease these folks refused to be vaccinated against, then you could sue the un-vaccinated for damages. The common good isn’t enough to encourage these folks. Perhaps threats to their pocketbook will be.

Vaccines: One Small Risk for a Child, One Giant Benefit for Mankind 10 November,2016Dr. Barry Starr

  • Anne

    Except it’s not a small risk. So many kids have died from vaccines. Google VAERS and then look at the data in there. It’s eye-opening, to say the least.

  • Bob Rehfuss

    What a great idea, sueing the unvaccinated when an immune compromised individual comes down with a vaccine preventable disease. If everyone were subject to being sued for the damage they impose on others they would not be more careful about their conduct. Whoops, my mistake, I forgot that the drug companies can do anything to our children via their vaccines and not be subject to any civil recourse in our courts.

    By the way, how does a child catch Hepatitis B or tetanus from my unvaccinated child?

  • Jessica

    Your “facts” are all wrong. Polio declined on it’s own BEFORE vaccinations. Try some research…
    The “Vaccine Safety Manual: For Concerend Families and Health Care Practioners” by Neil Z. Miller and get your facts straight.
    Also, more than half of the required vaccines are for “new” diseases & illnesses that did we did not have vaccines for years ago. Rotavirus vaccine? Hep B? Chickenpox? Are you serious?

  • Zubair

    The problem with the medical establishment is just that, it is the establishment. And anyone working as part of that establishment is only looking at what the establishment has prescribed.

  • I was hoping someone from the vast majority of people who vaccinate their kids would reply but I guess I’ll have to.

    I would urge folks to look at This is very well writeen and scientifically accurate. There is no reason for the CDC to fudge the data or hide facts.

    Even if a disease was on the decline before a vaccine was introduced, the vaccine eliminates it more quickly. And prevents new outbreaks from happening. How many extra polio victims would justify not using vaccines?

    My suing idea was just trying to come up with some way for people who do not do what is in the common good to be held accountable. I am open to other suggestions.

  • You are right, correlation does not imply causation. The argument of vaccination causing autism is tenuous at best. The fact is, the diagnosis of autism in the last two decades has changed dramatically. The definition and recognition of autism is now open to more symptoms than ever before.

    As far as requiring 100% of all children to be vaccinated, who knows. It could be that if at least 90% are vaccinated for disease XYZ then all 100% are safe. Epidemiological studies on what percentages are needed could shade light on this. Until that is done though, the benefits of vaccination to the child and community still outweigh the risks.

  • You are definitely right that 100% vaccination isn’t required. Some people can’t be vaccinated and for some the vaccination doesn’t take. I wonder what the real number is? I bet you could get some idea from looking at countries where the introduction of vaccines has been more gradual. Or from countries where a percentage of the population has opted out.

    It does raise another ethical issue though. Let’s say the 90% number is right. Who gets to be the 10% that gets totally risk free benefits at the expense of the other 90%? Do you figure who opts out by lottery?

  • Pingback: The Choice to Vaccinate | Stay September()

  • Concerned Mommy

    “One Small Risk for a Child, One Giant Benefit for Mankind” So you are saying that you don’t care about the children/families who have been harmed by vaccines as long as you can go along through life thinking you are safe from sickness, because you refuse to look at the real facts of how many came down with what, & instead are listening to the people who are making loads money off of every vaccine that they hand out…

  • Joe

    Your information is wrong. You are doing a true disservice to the people you serve. Learn the facts before being part of one of the worst cases medical malpractice in history. As you most likely don’t know it too 70 years to get Lead out of paint and gasoline due to faulty opinions like yours and corporate agendas. People do bad science these days for big paychecks, perhaps you are one of those people. There is a major lawsuit pending and over 1,000 peer reviewed journal articles clearly demonstrating the neurotoxicity of Thimerosal. The risk by 1999 was 1 in 250 children coming down with autistic symptoms. You mean well in your defense of vaccinations, I too think they are critical for a healthy society, but you are letting your desire for vaccines blur your judgment about unscrupulous corporations and cdc compliance. DO YOUR RESEARCH FOR REAL! Don’t just stop at one study, one article, look at the preponderance of peer reviewed studies dating back to the 1950s about the toxicity of thimerosal.

  • The fact that thimerosal can be neurotoxic at certain levels is undisputed. The question is whether or not the small amounts of thimerosal contained in vaccines cause autism. Since removal of thimerosal from vaccines in 2001, autism rates have continued to increase. One would expect them to decrease if thimerosal was responsible for the increase in autism.

    I wish thimerosal had been the culprit because then we would know the environmental trigger that can cause autism in certain people. Since it most likely is not the reason why autism rates have increased, we need to find out what the triggers actually are.

  • Andrew

    How about immunosuppressed children who may contract measles or mumps from a child who has recently recieved the live MMR jab thanks to viral shedding. see below link for a prome example.
    Who should they sue? the child or the vaccine maker or the Government?

  • Pingback: Quest Topic in the News: The Autism-Vaccine Connection | QUEST Community Science Blog - KQED()

  • Lancet issues full rejection of the original article that linked autism to vaccinations:

  • Elena Malkova

    Will you sue a vaccinated children if they still get sick “for damages”?

  • Barry


Dr. Barry Starr

Dr. Barry Starr (@geneticsboy) is a Geneticist-in-Residence at The Tech Museum of Innovation in San Jose, CA and runs their Stanford at The Tech program. The program is part of an ongoing collaboration between the Stanford Department of Genetics and The Tech Museum of Innovation. Together these two partners created the Genetics: Technology with a Twist exhibition.

You can also see additional posts by Barry at KQED Science, and read his previous contributions to QUEST, a project dedicated to exploring the Science of Sustainability.

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