Typical ABC news b.s.
These epidemiologists ( various links in article) show why HIT ( herd immunity threshold) may be reached with about 20% infected, since it is looking like 70% of us of more are already naturally immune based on exposure to previous coronaviruses. Or for as yet undetermined readons. However, it does explain the models.
That is why NYC and other large cities are not showing an epidemic of serious illness. They peaked. The huge population now being tested shows exposure...not illness. And largely among the young whose risk of severity was always lower. That cycle that NY is past, is now repeating in other states. But with better treatment, help from the natural environment of summer, better treatments....and smarter Governors.
https://off-guardian.org/2020/07/07/second-wave-not-even-close/
Coronaviruses aren’t all the same. That label really just refers to a general structure and says nothing about the antigens or behavior. For instance, HIV is a coronavirus. Are you saying if I get SARS-CoV-2, I’m now immune to HIV? Because I’m pretty sure I’m not.
The only other species to share the Sarbecovirus subgenus with SARS-CoV-2 is SARS-CoV (AKA 2003 SARS, about 9,000 people in the entire world infected). Sharing the Betacoronavirus genus are MERS-CoV (MERS (about 1,000 cases in the world) and HKU1 (under 100 cases in the world). Nothing else in the genus infects humans.
In other words, when we look at things that are at least somewhat similar to SARS-CoV-2, we’re looking at around 10,000 people out of 7,000,000,000 who would have had a previous infection with any chance at providing any immunity.