what does it mean to say that herd immunity will save us from the pandemic? as though it is some kind of "strategy" to get 70% of the population sick to prevent, what? 70% of the population from getting sick? what? this is an absurd narrative, built on a strawman that nobody ever presented.
so, again: we don't have a choice to choose herd immunity as a way out of anything. it's not a way out. rather, suggesting that public policy be based around the inevitability of herd immunity is coming to terms with accepting the reality that there isn't a way out, that this mess doesn't end until we all get the damn virus, and it just more or less burns itself out. we're then left with ways to try to shape the path to this endpoint, rather than deny it's inevitability.
so, if you want to talk about a strategy, that strategy would be trying to prevent the most vulnerable of people from getting the virus, as it inevitably spreads. but, that strategy does not involve the utilization of herd immunity as something that can be deployed, but rather seeks to adjust to it as reality as it presents itself. it would follow that restrictions on the vulnerable could lessen once the population reaches a substantive level of immunity. it's meant as an algorithm for least mortality.
and, if you realize that the algorithm for least mortality necessarily requires sheltering a substantive number of the population, it makes sense to actually bring in policies that would speed up the process.
but, this isn't a decision that we can make, and to suggest that reaching some place of herd immunity will stop an outbreak is asinine; herd immunity is the consequence of the outbreak, and a place we can get to quickly or slowly. that's the policy decisions...
now, what we've learned is that an immunity level of over 20% would appear to be enough to substantively slow the spread of the virus, even if we're only starting just right now to see very high levels of immunity in the hardest hit areas, like new york city.
now, that doesn't mean that every area that got hit hard will develop widespread immunity. it seems to be a developing sad reality that the vectors of spread in some regions were restricted almost entirely to medical facilities; that is, it doesn't seem like there was much spread outside of the actual hospitals, in some regions. that may mean that these regions are still vulnerable to the virus and may see another round of it, but it just brings up the point - this won't end until we get immunity up, one way or the other.
there have been some studies that suggest that asymptomatic carriers may not develop substantive antibodies. but, understand that what this is essentially saying is that the body wiped it out with something else - like t-cells - before the immune system could produce a response. so, it may be the case that people that catch the virus and eliminate it before getting sick don't produce antibodies for it, but that's not a reason to overturn the field of immunology and declare this virus to be unlike any other that we've ever seen. if the virus makes you sick, you will develop immunity to it, even if some people may be able to clear it without invoking an immune response...because it's so weak, in fact.
or, at least, you'd better hope that's true, or you're never going to get a vaccine to work.
all of these things may, indeed, slow down the process of developing mass immunity to this virus, but it doesn't change the inevitable outcome - we will be dealing with this in one way or another until we get to mass immunity, whether we like it or not.
and, it may change in the process, too, forcing us to start all over again. repeatedly...
"mom, why isn't there a vaccine for the common cold?"