The Research is still going on as various contradictory news are coming.

For example: WHO claims that "dead bodies are generally not infectious. Only the lungs of patients with pandemic influenza, if handled improperly during an autopsy, can be infectious".

But on the contrary a news came from from Thailand, reported in New york post mentioned that dead body transmitting the coronavirus to a living person and it  has been reported by scientists in Thailand.

So, research is still on and btw USA are now testing Sewage, because the community spread has been so massive that even USA isn't able to track each and everyone.