The US on Friday saw the highest daily increase in cases since May. We don’t need to test for herd immunity; it’s patently obvious we haven’t reached it.

Well, we probably had in most places. The variant changed the math, but we’ll get there soon enough again.

We don't need testing to figure out of we are at herd immunity. We know we are not, because the virus is spreading still and increasing speed now. It is only really an issue amongst unvaccinated. This population is basically anti-vax, apathetic, or children for whom the government has banned from getting the vaccine, regardless of circumstance.

In France, most people infected are young (< 55 years old), part of it because we could only access the vaccine at a later date than older people. Everyone that I know got their two shots, but most of them got the second less than a week ago.

Or, if you read the featured article, black people and native Americans who rightfully do not trust the racist medical system.

The problem with herd immunity is that the rate differs based on the variant. For something much more transmissible (like the Delta variant), herd immunity numbers are much different than for the original one. There's an argument that the US reached herd immunity on the original one pretty early on in vaccinations. And alpha with current vaccination rates. It's clear we haven't with Delta because numbers are going way up in unvaccinated people.

Immunity to one would be immunity to the other

They use the same vector for infection which so the immunities offer protection against. The protection mechanism is a game of catch up though.

You are thinking about individual immunity. The comment you were responding to was about herd immunity.

Herd immunity is when enough people have individual immunity that when those without immunity get infected so many of those around them are immune that the outbreak quickly dies out on its own.

Even if individual immunity is the same for variants A and B of some virus, if variant B spreads more easily than variant A then you will have to have a higher percentage of the population with individual immunity in order to have herd immunity.

Who are these people you imagine are willing to go in for comprehensive antibody testing but are refusing to take the vaccine.

People who don't want the vaccine and don't want to be harassed for it.

> People who don't want the vaccine and don't want to be harassed for it

That’s easy to do—stay on private property. This country’s laws were written to protect those rights. With WFH, it’s more plausible than ever.

Accepting proof of antibodies would be an even better way for everyone to get what they want right?

Unfortunately, no. Natural immunity is less durable against variants [1]. (Proof of exposure should be fine, though, for low-risk stuff in areas not undergoing an outbreak.)

Given that and assuming we’ll have a permanently unvaccinated population, the virus would be expected to keep reinfecting that group, thereby increasing the selection pressure for strains that reinfect.

[1] https://directorsblog.nih.gov/2021/06/22/how-immunity-genera...

The original paper [0] the article you quoted is based on doesn't say that the vaccine is better than natural immunity, just that it is different:

> Therefore, antibody immunity acquired by natural infection or different modes of vaccination may have a differing susceptibility to erosion by SARS-CoV-2 evolution.

They seem to be saying their tests showed that the vaccine antibodies better handled the receptor mutations they created (how much better? 100%? or 1%?), but that antibodies from a natural infection target other parts of the virus besides just the receptor (possibly offering broader protection).

> The neutralizing activity of vaccine-elicited antibodies was more targeted to the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein compared to antibodies elicited by natural infection. However, within the RBD, binding of vaccine-elicited antibodies was more broadly distributed across epitopes compared to infection-elicited antibodies.

[0] https://pubmed.ncbi.nlm.nih.gov/34103407/

Does this study actually conclude that vaccination is better at preventing being infected with variants? It looked to me that the study only proves that specifically the spike protein antibodies from the vaccine bind more generally than spike protein antibodies generated by a natural infection.

However during the course of a natural infection, antibodies would be generated for more targets on the virus than just the spike protein, wouldn’t it? Meanwhile the vaccine exclusively produces spike protein antibodies. This study doesn’t make any statements about how much effect those additional antibodies would have against variants.

The CDC estimates that about 114M Americans have been infected but only a quarter of those were officially counted as cases.

https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/burd...

> Why is there no widespread antibody testing to see if we've reached herd immunity?

Because then the show has to stop. It's pretty dark if you think about it long enough.