[BurningFrog]

Half-informed layman questions:

If this 30% recovered don't have antibodies, how did they beat the infection?

Does the immune system have some other mechanism to defat a virus?

Or does the antibody production taper off very fast for some people?

Or can the virus just die out by itself somehow?

[jacquesm]

You beat the infection due to a skirmish between your 'standard' immune system and the virus infected cells. As soon as you get a full-on immune system response there is a change and some more long term effects come into play. Nature tends to be very efficient, engaging an expensive mechanism apparently leads to caching the knowledge so it can be recalled when required, but if the expense outweighs the cost of doing so then it stays on a one-off basis.

The longer you deal with biology the more impressive it all is.

[eli_gottlieb]

That was such a good description of learning/updating in the immune system that I just had to go follow you on Twitter!

[somewhereoutth]

There is the innate immune system, and the adaptive immune system. If I understand correctly pathogen specific antibodies are created by the adaptive immune system, so maybe if the innate deals with the virus quickly the adaptive is not triggered.

There was a good TWIV podcast talking about this.

[nsxwolf]

If your innate immune system beats it, does that mean you're effectively already "immune" and are unlikely to develop serious COVID-19 disease when you catch the virus again, or was it just luck?

[LeoNatan25]

Probably luck. Given a much more potent viral load, it is more than likely the same patient can be infected again.

[nsxwolf]

There just doesn't seem to be any good news anywhere.

[BurningFrog]

That makes sense. I was not aware of the two separate immune systems.

So maybe 30% of people have an "innate" system well geared toward defeating this particular virus. Or/and they had a small exposure.

[megous]

Maybe non-specific immune response was able to kill off the virus early?

[jeffdavis]

That seems weird. The virus makes it through all of your defenses, which seems like the hard part, and then gets beaten once inside?

It's like the Trojan horse coming in, and the soldiers, once inside, getting arrested for tax evasion before they can open the gates.

[jjtheblunt]

I believe being homozygous for the delta32 mutation at the CCR5 gene locus is a possible example about which you ask.

https://en.wikipedia.org/wiki/CCR5