It's difficult to believe that people are still speaking about 'herd immunity' as if it's a real, proven concept with a virus like this. Highly mutate-able and animal RNA based. We have already seen people become infected multiple times all over the world. The aircraft carrier story is one of many. China has reported this, Iceland, Spain, Italy, Greece and many other countries that are doing better testing than the US have reported this as well.
To those that think you can become immune to CV, consider the simple flu. In the US people are vaccinated every year for "the flu". But really they are being given a vaccine that is aimed at 1-3 strains of what is forecast to be the dominant flu viruses to hit that year. Sometimes the forecast is right, sometimes it's not. Sometimes the vaccine helps a little even when it's wrong, because we humans have already been exposed to so many other flu strains over our lifetime.
None of that is the case with CV. There are multiple strains like the flu. But humans don't have prior history of exposure to animal based RNA CV. If you survived the bird flu, SARS, MERES, etc, you may have some antibodies in your system that might help you fight off this CV. That's a small number of people in the world and an even smaller number of people in the US.
Corona Virus is not one virus. CV-19 is just the latest discovered. Our bodies don't know how to fight this. Other issues can make it more difficult, or help the virus get a stronger hold inside us. Heart disease, high blood pressure, (look up beta blockers), diabetes, etc.
The big problems are that so much is unknown, or not being shared with the public. Never mind the lies from all of the governments to their citizens and the contradicting statements. "Wearing a mask doesn't help" A month later, "everyone should wear masks", (both from Dr F). The earlier lie may have been ignorance, or may have been because of the mask shortage and the Government wanting masks to go to professionals, not the average citizens that had less exposure risk.
Wearing a mask is possibly better at protecting the people around you than protecting yourself. It's about the moisture in your breath not projecting at others around you. If they are wearing masks, that helps protect you. It's not so much about what you're breathing in thru the mask. This virus, like nearly all viruses, needs a moist environment to survive any length of time. So it's about what people are breathing out.
Maybe I missed it, but I haven't seen or read any clear reports of confirmed contact exposure. (a person getting CV from touching a contaminated hard surface), OTOH, one person exposing dozens or hundreds of others in close proximity is all over the news. One sick person going to church infecting 100+ others. One sick worker infecting 100s of other works at the same plant. There are lots of this kind of report. From early days to today. That's not one person coughing all over everyone. That's one person breathing in and out in the same confined space as others.
We still don't know if all these people testing positive with no symptoms can spread the virus to others or not. And by and large, the far greater number of people are the un-tested. No symptoms, no apparent reason for a test, so they remain unknown. That's what social distancing and masks are attempting to protect the masses from.
Strictly IMHO, even if and when a vaccine is released for public use, I seriously doubt it will be any more successful than the flu vaccine is now. It will help some, not others and it will be a crap shoot against a constantly mutating virus that we have little previous exposure to. Maybe decades from now we'll have some broader immunity. But this isn't polio or chicken pox. You can't eliminate it by vaccinating everyone. At best, you'd only have immunity to one strain of CV. Like the shoe bomber, the one we already saw, not the next one.