Luck just means "I don't understand the math... yet"
No one knows. No one really knows how many people had the disease, or have the disease currently.
Here's a great example. According to John's Hopkins, Santa Clara County has had a total of 1,870 cases. Divided by 1.93 million county population, that yields a disease incidence rate of 0.097% (or about .1% for easy math). However,
in a recent study by Stanford University, they did a statistical sample of county residents and found that "
between 48,000 and 81,000 residents in Santa Clara County were infected as of April 1" (at a time when the confirmed case count was slightly less than 1000). The study found that "
The number of coronavirus infections in Santa Clara County could be between 50 and 80 times higher than the officially confirmed count".
Given our ignorance in this area, it is possible to conclude that some parts of the country, where testing is indicating close to 1% case rates, may be approaching the 20 - 40% level where herd immunity starts to come into play. Even on this site, we have a number of members saying "I think I may have had it." Even my WIFE is now saying she thinks she may have had it back in January... and I recall a period where I was wiped out and felt like I couldn't get out of bed, but assumed it was due to stress and travel. Heck, given asymptomatic case rates, it is likely that several members of this site have had it, and never felt a thing.
If you follow this logic, the irony is that many people sheltering in place are already immune. Of course, that is what the government has been telling us all along - that they are unable to stem the natural tide of this disease without a vaccine, and the best they can hope for is to slow it down so that our medical facilities aren't overwhelmed when dealing with the small percentage of severe cases.