Cows, Vaccines, and the Plural of Anecdote
I once heard someone say that the primary difference between humans and animals is that humans learn from others’ mistakes. Animals, by contrast, only learn from their own personal experience with their environment. As I reflected on this observation, I realized that we humans certainly do value personal experience, but that we’re also capable of modifying our perceptions of reality with new information gathered from others. And best of all, we have the flexibility to change our minds about our conclusions when we repeat our observations under controlled conditions.
Smallpox is a deadly virus that kills about 33% of its victims, and badly disfigures the rest. In the 1700′s this scourge was greatly feared throughout Europe. Thanks to a keen observation by a British farmer (Benjamin Jesty), a new mechanism of protection against smallpox was discovered. Jesty noticed that people who milked cows infected with a similar disease (cowpox) did not seem to come down with smallpox. He theorized that exposure to pox-infected cows was a key to immunity against smallpox, and his theory was proven correct by physician Edward Jenner about 20 years later. Dr. Jenner created a reliable means of exposing people to the cowpox virus (called a vaccine – “vacca” meaning “cow” in Latin), introducing a tiny amount of cowpox-infected fluid under the skin to confer immunity against smallpox. This whole process of observation, careful experimentation, monitoring results, and further refining procedures led to the world-wide eradication of a deadly disease. Similar principles were applied to other illnesses, further reducing the global disease burden of polio, measles, mumps, rubella, and many other viral infections.
I suppose that one could thank cows for advancing the field of immunology more than any other animal – and thank a certain farmer for being so keenly aware of his cows’ health and their impact on humans (you know I have a soft spot for cows). But the story didn’t end with Jesty’s anecdotal observation - his theory was born out by science. His observations were repeated again and again in successful innoculation trials, and refined to a point where millions could benefit from vaccines.
Nowadays people are very impatient. We have short attention spans, we want instant gratification, and we are prone to jumping to conclusions about pretty much everything, especially medical news. I can’t tell you how many quantum leaps I’ve observed in health reporting - like the case where a scientist noted that breast cancer cells express a different protein in the presence of olive oil extract (in a Petri dish) and then reporters translated that news into “olive oil cures breast cancer.” All this ignited by the instantaneous availability of information via the Internet, curious minds, and lack of proper scientific vetting.
What happens today is that a plural of anecdote becomes “evidence” of cause and effect. These false assumptions then become entrenched, and end up as “public knowledge” long before they’ve been tested for reproducibility. The cart is well and truly before the horse in most health reporting, and this has done incredible damage to us as a society. Our insatiable desire for answers has outstripped our patience for finding truth.
Consider the recent scare about vaccines and autism. A few people noticed that clinical signs of autism occur at around the same time that some vaccines are given to children. They wrongly assumed that vaccines caused autism, and that misconception has traveled so far and wide that parents are actually choosing not to vaccinate their children against preventable diseases. Measles have made a resurgence, and some are warning of the return of polio. These diseases are absolutely preventable – and it’s tragic that we may have to relive these scourges to remind people of the value of vaccines.
The best part of being human is that we can learn from others’ mistakes. We do not have to live through the mistakes ourselves to change our behaviors. I do worry that the anti-vaccinationist movement represents a regression backwards towards animal type thinking. Will it take a wave of paralyzed children to wake us up to the value of vaccines? Will Jesty’s cow have to tell us “I told you so?”
I’d like to think that we’re beyond that. But I guess only time will tell if people will fall for the plural of anecdote in lieu of truth. Our country’s health hangs in the balance as the Internet fuels both science and folly. Hold on to your skepticism, folks. It could save your life.
This post originally appeared on Dr. Val’s blog at RevolutionHealth.com.
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