Well, we know what it has done, and we know that it is very contagious. We know it can be a lot more dangerous to people than the cold or the flu. We know that masks help prevent the spread, along with simple things like washing one's hands. We know that countries that were cautious are doing a lot better than countries that are not. Look at Sweden, which tried the herd immunity route, or the USA, which we can see in this thread is no surprise when propaganda so easily makes its way into the discussion. What hasn't been determined yet, as far as I've seen, is how quickly this virus mutates, which will determine how effective a vaccine might be. It looks like some promising progress has been made in this area, but I think it's a little too early to tell. We haven't determined the long term effects on folks who survive the virus yet, though there is some indication that permanent lung damage and other things like that could result.