Herd immunity? Is it proven that immunity lasts long enough to provide coverage to the herd? The issue I have is that if we overload our medical system - just

Herd immunity? Is it proven that immunity lasts long enough to provide coverage to the herd? The issue I have is that if we overload our medical system - just go on twitter to see the horror stories posted about ICUs and medical staff in serious depression - then even if you have a totally managable non-COVID acute issue, you could get infected or die by lack of treatment because the system is at or beyond capacity. We are in a fight to keep our current medical system running. If you overload it recovery for that may take longer than the hypothetical herd immunity or vaccine. For curves: Flat = working. exponential = not working.