I am even surprised too, I thought Italy would have the biggest number of cases but they were surpass by the US, maybe because the measure done by the US is not so strict that even the NBA are still considering of continuing the season with the idea they presented.
To be honest, I wasn't surprised with the US surpassing Italy in the number cases, after the first few NBA players tested positive, I knew that the virus must spread a lot during those games without anyone noticing due to how long it could take before the symptoms could surface.
This would be far from perfect, but I guess it would still be better option that completely cancelling the season. Personally, it will be miracle if they can pull off this. It will be interesting to hear players opinion, as they are the ones that will be endangered the most, and consequently. Maybe players could be in some kind of quarantine during finals series, to minimise the risk of spreading the virus.
Any decision taken by NBA as to how to finish the season would be far from perfect, if it's not the native playoffs format. However, they'd would be looking to savage as much as they can from whatever is left, so even more drastic measures could be considered.