The herd immunity theory is in serious doubt

Covid-19 Antibodies Waning Over Time

The herd immunity thesis claims that if enough people get Covid they will become immune to reinfection slowing the spread of the disease.

However, an Antibody Study Shows Immunity May Wear Off.

The survey of 365,000 adults in England who tested themselves at home using a finger-prick test showed the proportion of people testing positive for Covid-19 antibodies declined by 26.5% between June 20—12 weeks after the peak of infections in the country—and Sept. 28.

Doctors don’t yet know whether antibodies confer any effective immunity against reinfection by Covid-19. But even if they do and the results of this survey are confirmed, it suggests the prospect of widespread long-term herd immunity to the virus will be difficult to achieve. Herd immunity occurs when enough people in a population develop an immune response, either through previous infection or vaccination, so that the virus can’t spread easily and even those who aren’t immune have protection.

The authors admitted the trial had limitations. “It included nonoverlapping random samples of the population, but it is possible that people who had been exposed to the virus were less likely to take part over time, which may have contributed to apparent population antibody waning,” they said.

Blow to Herd Immunity Theory

A 26.5% reduction in antibodies in just 12 weeks is quite a significant reduction. 

If accurate, it calls into question expected results from vaccines as well. 

Whereas I stated "if accurate" and "calls into question" the Financial Times says Covid-19 herd immunity theory dealt blow by UK research.

Jonathan Ball, professor of molecular virology at Nottingham university, said that while the React-2 study “confirms suspicions” about waning immunity in elderly populations, it is less clear what the relationship is between declining immunity and susceptibility to reinfection.

False Promise of Herd Immunity 

Nature.Com discusses the false promise of herd immunity for COVID-19.

Proposals to largely let the virus run its course — embraced by Donald Trump’s administration and others — could bring “untold death and suffering”.

In early October, a libertarian think tank and a small group of scientists released a document called the Great Barrington Declaration. In it, they call for a return to normal life for people at lower risk of severe COVID-19, to allow SARS-CoV-2 to spread to a sufficient level to give herd immunity. People at high risk, such as elderly people, it says, could be protected through measures that are largely unspecified. The writers of the declaration received an audience in the White House, and sparked a counter memorandum from another group of scientists in The Lancet, which called the herd-immunity approach a “dangerous fallacy unsupported by scientific evidence”.

“Surrendering to the virus” is not a defensible plan, says Kristian Andersen, an immunologist at the Scripps Research Institute in La Jolla, California. 

“Attempting to reach herd immunity via targeted infections is simply ludicrous,” Andersen says. “In the US, probably one to two million people would die.”

Guessing Game

Clearly everyone is guessing. 

It's equally clear that herd immunity proponents are making potentially disastrous guesses.

The same applies to the notion that vaccines will be immediately successful.

But the worst guess goes to Donald Trump who stated on February 26, "The 15 (cases in the US) within a couple of days is going to be down to close to zero.”