Lets see. It takes a few days possibly a bit longer from the moment your infected to the illness progression and the time your better that can take up to 28 days or therabouts, in that time your infectious to others.
So we start a total lockdown today so how long before the ilness has has had no one to infect?, it dosent "jump" in a mysterous way the viral particles are very small but not as small as some.
So if, and its a very big if, no one conected no one else then give it a month and the infection rate will drop right off. However then it will rise again the moment you relase the lockdown as some peole will still be infections thats where better and easier and quicker testing will be very usefull.
Apart from that some drug trails are under way one of them's looking very good indeed and others are on the way, a lot of people are working on this right now.
One thing that could be a game changer is a much better face mask and filter that might allow quite a few people to go back to work. OK not much fun wearing one but perhaps a small price to pay in order to get the economy back on some sort of recovery.
It does make me wonder that in every pictiure you see from Aisa everyones get a mask on. OK present ones arent that effective but as Tescos say every litte helps!, better masks and better the reduction in illness spread!.