This commentary was previously a part of my daily COVID19 analysis on 5/9/2020, but is presented here independently for ease of reference and to avoid re-sharing in each day’s report. As always, my training is not in epidemiology, and I defer to recognized experts for more in-depth explanations. This analysis is an attempt to convey the basic limitations of relying on a “common sense” approach and provide commentary about whether we can anticipate it as a solution to the current virus outbreak at a level that is approachable to an untrained reader.
I want to take a moment and talk about the “use common sense” talking point that’s been going around. It usually goes something like this “it’s all safe and fine, just use common sense and you won’t get sick”. Aside from the clear victim blaming elements, it fails to understand the way “common sense” works.
Common sense relies on people’s ability to accurately estimate the risk that a given activity poses, and moderate their behavior accordingly. That’s fine for many threats — when a stray dog growls and barks at you, you can easily assess the risk and avoid the harm. But it doesn’t work when threats aren’t highly visible, and when you’ve got bad heuristics about what constitutes a threat.The invisibility of the threat is multi-factored, which makes it almost impossible to use common sense to navigate.
First, the contagion is microscopic. This means you cannot see it in the air or on surfaces that you encounter. Even if you haven’t had any contact with another human being, there’s no way for you to know whether something you touch is contaminated. Thus, you can’t guess whether it’s safe to touch something out in public.
You also can’t tell who is infected. This is true both of the large number of asymptomatic but contagious people, and of the symptomatic who are simply masking their symptoms (good luck visually spotting the guy with the fever in line at Walmart). You can’t even tell for sure if you’re infected yourself. This means that avoiding infected people is impossible, short of avoiding all people. When you take these two items together, it becomes clear where many of the 6-foot rules don’t hold up well. If I’m potentially spreading contagion in a 6 foot moving bubble around my person, and you enter the area where I was just moments ago, the risk is still there. The only difference is that we can all pretend that we were following guidelines. This is why physical distancing doesn’t work in classrooms, homes, or other places people congregate.
Common sense also leads us to some unhelpful responses. Because we cannot see contagion, we substitute stimuli associated with it as signals. Hence, we treat people using PPEs as though they’re infected, we profile people based on their race and ethnicity, and we treat every pollen-related sneeze as a personal attack. And because this feels like doing something, we don’t attend to real risks.
In the absence of the ability to objectively assess immediate risk, we have to take a statistical approach — something that our brains are bad it. Since we can’t eliminate all possible exposure (hermits in well-supplied bunkers excluded), we have to take steps to minimize it instead. This is where we’ve failed — we’ve conflated “minimize” with “reduce”. We’ve done it because it’s convenient, and because our brains keep telling us “I don’t see any obvious threat, so it must be OK” — common sense is literally encouraging us to be unsafe.
In summary, common sense is why infection control is failing in GA, and across the US. Common sense is what makes liars pushing anti-vaxxer talking points and fake cures so profitable. Common sense has killed over 100K US so far. Let’s not use common sense about this.