[M T]

Everyone gets colds.  Without further evidence, I'd guess we've all had the several forms of coronavirus colds.   So, is the difference in outcomes for COVID-19 related to, perhaps, how recently you one (or several) of the coronavirus colds?

It would be interesting to know this.  Perhaps there are some people for whom records exist of whether they tested positive for one of those strains.  Then they could be surveyed to see if they had COVID-19 subsequently, and whether they had an asymptomatic, mild, or severe form.

I don't know what the fatality rate is for these colds.  I presume pretty low for everyone with a functioning immune system.  Personally, I might be willing to get a cold (or several) if I expected it would give me some beneficial effect against COVID-19.  I can't see the FDA every approving people seeking out colds though.  But I could imagine a vaccine using inactive cold virus.

I'll note that their tests against 2015-2018 blood samples in the study don't necessarily mean that those people whose blood that is, still have beneficial effects (if any ever existed) against COVID-19.  Any effects may have lasted just a few months.   (It would also be interesting to see the dates of the samples, marked with the amount of reactivity to COVID-19, plotted against the prevalence of the colds during that time frame.  That might be difficult because different areas may have their cold season a month or two displaced from other areas.)

[M T]

Everyone gets colds.  Without further evidence, I'd guess we've all had the several forms of coronavirus colds.   So, is the difference in outcomes for COVID-19 related to, perhaps, how recently you one (or several) of the coronavirus colds?

It would be interesting to know this.  Perhaps there are some people for whom records exist of whether they tested positive for one of those strains.  Then they could be surveyed to see if they had COVID-19 subsequently, and whether they had an asymptomatic, mild, or severe form.

I don't know what the fatality rate is for these colds.  I presume pretty low for everyone with a functioning immune system.  Personally, I might be willing to get a cold (or several) if I expected it would give me some beneficial effect against COVID-19.  I can't see the FDA every approving people seeking out colds though.  But I could imagine a vaccine using inactive cold virus.

I'll note that their tests against 2015-2018 blood samples in the study don't necessarily mean that those people whose blood that is, still have beneficial effects (if any ever existed) against COVID-19.  Any effects may have lasted just a few months.   (It would also be interesting to see the dates of the samples, marked with the amount of reactivity to COVID-19, plotted against the prevalence of the colds during that time frame.  That might be difficult because different areas may have their cold season a month or two displaced from other areas.)