How can a disease with a 1% mortality rate shut down the U.S? Answered by Franklin Veaux:

[Celerity]

81. +100000

also, Veaux, the author of the OP is pushing pure quackery

herd immunity would kick in well before you got to a 100% viral penetration rate

that is the most basic of epidemiological science

at what level herd immunity kicks in is determined by the R-naught value (basic reproduction number)

a simple formula for calculating the herd immunity threshold is 1 − 1/R0

If the R-naught is 1.5.you need a 33.3% exposure rate to hit herd immunity
If the R-naught is 2.0 you need a 50% exposure rate to hit herd immunity.
If it is 2.5, then 60% is need to reach herd immunity
If it is 3.0, 66.7% exposure rate needed
If the R-naught drops under 1.0 and sustains at that level, the viral disease will burn out


also see this

Immunity to COVID-19 is probably higher than tests have shown

https://news.ki.se/immunity-to-covid-19-is-probably-higher-than-tests-have-shown

New research from Karolinska Institutet and Karolinska University Hospital shows that many people with mild or asymptomatic COVID-19 demonstrate so-called T-cell-mediated immunity to the new coronavirus, even if they have not tested positively for antibodies. According to the researchers, this means that public immunity is probably higher than antibody tests suggest. The article is freely available on the bioRxiv server and has been submitted for publication in a scientific journal. “T cells are a type of white blood cells that are specialised in recognising virus-infected cells, and are an essential part of the immune system,” says Marcus Buggert, assistant professor at the Center for Infectious Medicine, Karolinska Institutet, and one of the paper’s main authors. “Advanced analyses have now enabled us to map in detail the T-cell response during and after a COVID-19 infection. Our results indicate that roughly twice as many people have developed T-cell immunity compared with those who we can detect antibodies in.”

In the present study, the researchers performed immunological analyses of samples from over 200 people, many of whom had mild or no symptoms of COVID-19. The study included inpatients at Karolinska University Hospital and other patients and their exposed asymptomatic family members who returned to Stockholm after holidaying in the Alps in March. Healthy blood donors who gave blood during 2020 and 2019 (control group) were also included.

T-cell immunity in asymptomatic individuals

Consultant Soo Aleman and her colleagues at Karolinska University Hospital’s infection clinic have monitored and tested patients and their families since the disease period. “One interesting observation was that it wasn’t just individuals with verified COVID-19 who showed T-cell immunity but also many of their exposed asymptomatic family members,” says Soo Aleman. “Moreover, roughly 30 per cent of the blood donors who’d given blood in May 2020 had COVID-19-specific T cells, a figure that’s much higher than previous antibody tests have shown.” The T-cell response was consistent with measurements taken after vaccination with approved vaccines for other viruses. Patients with severe COVID-19 often developed a strong T-cell response and an antibody response; in those with milder symptoms it was not always possible to detect an antibody response, but despite this many still showed a marked T-cell response.

Very good news from a public health perspective

“Our results indicate that public immunity to COVID-19 is probably significantly higher than antibody tests have suggested,” says Professor Hans-Gustaf Ljunggren at the Center for Infectious Medicine, Karolinska Institutet, and co-senior author. “If this is the case, it is of course very good news from a public health perspective.” T-cell analyses are more complicated to perform than antibody tests and at present are therefore only done in specialised laboratories, such as that at the Center for Infectious Medicine at Karolinska Institutet. “Larger and more longitudinal studies must now be done on both T cells and antibodies to understand how long-lasting the immunity is and how these different components of COVID-19 immunity are related,” says Marcus Buggert.

snip


Publication

https://www.biorxiv.org/content/10.1101/2020.06.29.174888v1

“Robust T cell immunity in convalescent individuals with asymptomatic or mild COVID-19”

Takuya Sekine, André Perez-Potti, Olga Rivera-Ballesteros, Jean-Baptiste Gorin, Annika Olsson, Habiba Kamal, Sian Llewellyn-Lacey, David Wulliman, Tobias Kamann, Gordana Bogdanovic, Sandra Muschiol, Elin Folkesson, Olav Rooyackers, Lars I. Eriksson, Anders Sönnerborg, Tobias Allander, Jan Albert, Morten Nielsen, Kristoffer Strålin, Sara Gredmark-Russ, Niklas K. Björkström, Johan K. Sandberg, David A. Price, Hans-Gustaf Ljunggren, Soo Aleman, Marcus Buggert, Karolinska COVID-19 Study Group.
bioRxiv, online 29 June 2020, doi: 10.1101/2020.06.29.174888