Thread by @vipintukur

A very interesting yet a bit complicated paper. First, let’s go through the key findings of the paper:

1) the distribution of viral loads observed in asymptomatic population was indistinguishable from what has been reported in hospitalized populations 1/

2) regardless of symptomatic status, approx. 50% of individuals who test positive for #SARSCoV2 seem to be in noninfectious phases of the infection 2/ pnas.org/content/118/21…

3) just 2% of infected individuals carry 90% of the virions circulating within communities, serving as viral “supercarriers” & likely also superspreaders 3/

pnas.org/content/118/21…

Now some explanations: This study is NOT suggesting that 2% of people cause 90% of transmission.

Rather that most infected ppl pass through peak viral load and in doing, contribute to that 2% for 1-2 days 4/

The paper suggests that symptoms do not determine viral load and thus transmissibility. Only Virus load does - regardless of symptoms. 5/

By @michaelmina_lab:
Most infected people likely pass thru “super carrier” state. People achieve same virus load regardless of symptoms. Most symptoms due to immune responses, not virus. Can be inverse relationship:stronger immune response, more symptoms but lower viral load 6/

Further explanation by @michaelmina_lab:
“When ppl become infected the viral load increases a billion-fold. But only stays at such a HIGH load for a short duration (hours - 2days). if someone goes into a bar during those hours...”. 7/

“.....on the other hand, if that very same person goes into that very same bar with the very same people in it, but 3 days later, the viral load may be reduced a million-fold (literally)& no longer a superspreader. Infection status is all probability & time” 8/

So, the title of the paper seems a bit misleading. What the study indeed reveals that at any given “snapshot of time”, 90% of the virus is carried by 2% infected. Everyone goes through that peak! 9/