Hacker News Reader

Comment by sovnade | Hacker News Reader

Am I reading the conclusion correctly that people who were infected with some strain of COVID and received two doses of the vaccine fared better against future variants than people who only received the vaccine?

View on HN

I think that's somewhat expected, and basically analogous to "defense in depth". The mRNA vaccines only code for the characteristic spike protein, but an actual infection can result in developing antibodies against multiple features on the surface of the virus. Both being better than either alone is reasonable result of that.

The problem with natural immunity is that it can be so variable. Some people would develop better immunity from being infected than they would from just the vaccine, but some would develop much weaker immunity from the infection.

> The problem with natural immunity is that it can be so variable. Some people would develop better immunity from being infected than they would from just the vaccine, but some would develop much weaker immunity from the infection.

And some will develop autoimmune disorders. The mRNA vaccines being highly specific is an important safety feature.

Here's an interesting article I just found, which discuesses the virus-autoimmunity connection: https://www.nature.com/articles/d41586-021-01835-w

It's been theorized for a while. For Multiple Sclerosis - an autoimmune nerve disease - a curious phenomenon is that 100% of patients have been infected with EBV, the cause of mono, while the base rate in the population is about 90%.

It is probably also worth noting that while this sort of defense in depth provides the strongest protection, the risk involved with the first infection probably means that you are better off in trusting the vaccine. Infection prior to vaccination may provide a stronger immune response, but only if you survive the infection.

Oh, absolutely. I think I unintentionally implied that just getting infected was a good strategy, but I 100% agree. The vaccine is awesome, and a far superior option.

It's also hard to actually compare those things because there's an enormous literal survivor bias here. The living population of previously infected people have already demonstrated the ability to survive COVID.

If you took those same people, and magically made them immunologically naive, they would fare better than a random sample.

Does "fare better" include the risk of the first infection? Otherwise it seems somewhat contrived.

Yes, and in that order (first infection, then vaccine).

Another study: https://www.nature.com/articles/s41586-021-04005-0?f

Reply on news.ycombinator.com