CNBC’s Rick Santelli recently suggested that everyone contract coronavirus, like a chicken pox party in the 1990s (or a measles party for the anti-vaxxers). It was a cold, capitalistic case for the sake of the global markets. But to be fair, scientists have argued for decades that we can build stronger immune systems via more germ and bacteria exposure. In fact, since 2014, many headlines have instructed us to throw out our hand sanitizer because it was making our immune systems soft (and now we’re supposed to swear by the stuff?). More largely, there’s a whole field of study around figuring out what type of exposure (and how much of it) can benefit our immune systems.
But before we all start coughing into each other’s mouths, it’s crucial to understand where this theory comes from, how it works and what it means for the current coronavirus pandemic.
“The hygiene hypothesis” was proposed by epidemiologist David Strachan in 1989 and theorized that exposure to certain infections during early childhood may have made our immune systems stronger, and by extension, a lack of exposure now has weakened them. It was a pretty broad theory with a lot limitations that microbiologist Graham Rook revised in 2003, with the “old friends hypothesis.”
He found that exposure to colds, influenza and measles didn’t boost immunity, rather it was exposure to very specific organisms (intestinal worms, protozoans and gut bacteria mostly) previously present in hunter-gatherer societies that helped to prevent conditions like allergies, digestive problems, inflammatory diseases and even multiple sclerosis. (This is the reason why someone from the U.S. can easily get sick from the water in less developed countries, while someone born there wouldn’t have the same problem, as they’ve been exposed to very low levels of the same bacteria.)
Unfortunately, by then, the hygiene hypothesis had been around for more than a decade and most people weren’t interested in the nuance around it. We were just psyched about having an excuse to not wash our hands, which was the last thing researchers wanted. As such, we completely overlooked that the fundamental difference between the organisms we want to be exposed to and the flu (or COVID-19) is modernization. Protective microbes have been phased out due to the otherwise positive aspects of our collective evolution — sanitation, clean water, toilets and soap — whereas the flu and coronavirus come from a post-modern world and aren’t protective at all.
“What you didn’t pick up from these hunter-gatherer societies was the flu or COVID-19, because we didn’t fly back then to deliver them. So they have really different effects on our immune systems,” explains William Parker, associate professor of surgery at Duke University.
Basically, the fact that the flu and coronavirus are comparatively new to our immune systems is precisely why a person shouldn’t try to purposefully contract them just to “get it over with.” If anything, Parker warns, it could trigger other autoimmune diseases in response, which “makes biological sense because they probably didn’t exist prior to 10,000 years ago, so our immune systems haven’t adapted to them.”
“A worm might prevent or eliminate a seasonal allergy,” he continues, “but having the flu or COVID-19 doesn’t have that same calming effect on the immune system.”
So two things: 1) the hygiene hypothesis is exactly that — a hypothesis; and 2) Santelli is exactly what he plays on TV — a cable news blowhard, meaning his medical hypotheses don’t even register as a worthwhile guess.