Originally Posted by
rickair7777
Given that natural immunity for the four human coronaviruses that cause colds seems to only last nine months it was unlikely we were going to get much more than that out of a vaccine. 18 months maybe if we are lucky? But that’s only a guess and we won’t know until the time’s up. Right now we can only extrapolate a few months out. You don’t know for sure until it actually happens.