Amid the serious Covid warnings, one important fact is largely ignored: business has fallen by 77% in the past six weeks. If a medication reduces the cases by 77%, we would call it a miracle pill. Why is the number of cases declining much faster than experts predicted?
Largely because the natural immunity to previous infection is much more common than can be measured with testing. Only from 10% to 25% of the infections were tested, depending on when someone got the virus during the pandemic. Applying a time-gun prisoner of 1 in 6.5 to the cumulative 28 million confirmed cases would mean that about 55% of Americans have a natural immunity.
Now add people who are being vaccinated. This week, 15% of Americans received the vaccine, and the figure is rising rapidly. Former Food and Drug Commissioner Scott Gottlieb estimates that 250 million doses will be delivered to about 150 million people by the end of March.
There is reason to think the country is rushing to an extremely low level of infection. Since more people are infected, most of whom have mild or no symptoms, there are fewer Americans who can be infected. On the current trajectory, I expect Covid to mostly disappear in April, which will enable Americans to resume normal life.
Antibody studies underestimate natural immunity. Antibody testing does not detect antigen-specific T cells, which develop ‘memory’ once activated by the virus. Survivors of the Spanish flu of 1918 were found that memory cells in 2008 – 90 years later – were still prone to neutralizing antibodies.