COVID-19 DAY 81: The Scariest Thing Last Halloween May Have Been COVID.

People have been alarmed by the “new strains” of COVID-19 being discovered around the world. Part of this confusion is due to the somewhat subjective use of the term “strain” which applies to any genetic variation or subtype of a virus. These variations can cause a change in a virus’ lethality or infectiousness or as is more often the case, no discernible change at all. In fact, because genetic mutations occur constantly as a virus replicates in the human body, a single individual could theoretically develop different strains of a virus within their own course of an infection.

There were some early theories circulated that the reason why some people experience only mild symptoms vs life-threatening symptoms could be due to differences in strains. The strain found in NYC was traced to Italy and both regions had the highest number of deaths in the world. Unfortunately, this theory falls apart because the Italian strain was the same strain that infected Germany and Noway which had very few deaths.

There is only one virus that causes COVID-19, SARS-CoV-2. There are 2-8 easily detectable strains of SARS2 which has helped researchers trace the geographic path of the pandemic, starting in Wuhan China and spreading to Europe, South East Asia, and North America and from there to other parts of the world. From each of these 8 regional strains, hundreds of different variations have been identified by more detailed genetic sampling.

Mutations happen naturally in the process of viral replication and geneticists have learned that this randomness happens at a regular rate over time. By determining how often mutations occur, a ‘molecular clock’ can be calibrated for any organism. Running back the molecular clock from the various SARS2 samples from around the world, they were able to estimate that the original strain of SARS2 could have appeared as early as October 2019. So yes, it’s possible that the flu you had back in December could have been COVID-19. It didn’t even have to be a bad case of flu, as some COVID-19 systems are as mild as a cold or allergy. Only a serum antibody test can determine for sure.

Molecular clocks can help us turn back time to the start of the pandemic. What they can’t do is tell us how the pandemic started. And unfortunately we can’t turn back time to stop it.


SOURCES

https://medium.com/@tomdelmundo/covid-19-day-38-the-mutant-threat-is-overblown-1110bcabe533

https://www.scmp.com/news/china/science/article/3079678/coronavirus-mutation-threatens-race-develop-vaccine

https://nextstrain.org/ncov/global

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