Might a robust testing-and-tracing regime identify a non-virulent coronavirus mutation, which could then serve as the moral equivalent of a vaccine?
(Dammit, Jim, I’m a lawyer, not a doctor! Though I did study population genetics as an undergrad, a long, long time ago. So I’m just spitballing this in the hope that others here with more relevant credentials can give it a sanity check, and if it passes, forward the thought to someone who could use it.)
Here are my premises, which I’ve seen attributed to credible experts: Coronavirusus, being RNA-based and otherwise fragile, tend to mutate. Some mutated strains, while remaining contagious and infectious, are considerably less harmful to those infected. Such strains may have an advantage in the evolutionary competition among coronavirus strains for human hosts, as their hosts are more likely to contact potential new hosts. This phenomenon is thought to have contributed to the end of the 2003 SARS outbreak. Also, those infected to date with the 2019 novel coronavirus have experienced a very wide range of consequences; for many, there are no significant symptoms, and no reason to expect long-term damage to their health.
I think it follows — but I invite correction — that: At some point, a more or less innocuous strain of the novel coronavirus, one which rarely or never produces the COVID-19 disease, is likely to emerge. Indeed, that may have already happened, and might explain some of the wide variation in infection outcomes, national case fatality rates, etc. A rapid and robust testing-and-tracing regime might identify large infection branches with surprisingly low or mild disease incidence — e.g., a situation where an individual has acted as a “superspreader,” leading to many infections, including members of usually vulnerable populations, but none of those infected show severe symptoms. Tracing that back, sequencing the genome of that “novel novel coronavirus,” and subsequent testing for that specific strain, might identify a population of hosts of a benign variant. In a controlled way, such hosts could then be allowed relatively unrestricted social contacts, while initially avoiding the most vulnerable. That might open a path toward hastening herd immunity with reduced damage on the way.
If this line of thinking is valid, I expect the epidemiological experts already know all about it. But I’m not seeing it in general public discourse, and it seems to me that it provides a politically powerful argument for increased testing and tracing. (Not that we should need more reasons, but that seems to be the reality.) It would mean that such action, in addition to being key to reducing harm from social re-opening while society searches for a vaccine, would act as part of the search for a vaccine equivalent. That would bring to the discussion a much-needed element of “hope and change.”
In short: The solution to COVID-19 may already be walking among us. Let’s go find it!