In an open letter the group, mostly made up of doctors working in the Welsh NHS, called for scrutiny of the "decisions and actions undertaken" so far so that lessons can be learned.
It said a probe should examine how health care organisations can reduce deaths related within hospitals, and what support is offered to people with long Covid.The letter calls for an investigation "undertaken without delay so that lessons can be learnt as we head into further waves of COVID-19 infections with the possibility of new vaccine resistant strains ahead and normal winter pressures".
"One in three people in certain health boards were acquiring the Covid virus in a hospital setting because of the decisions taken here in Wales," he said.Plaid Cymru health spokesman Rhun ap Iorwerth said: "I think, in all honesty, that opens you up to the charge of ducking scrutiny."