Roy Kilpatrick, former chief executive of HIV Scotland, predicted an increase in HIV infections and other sexually-transmitted diseases and he accused police and council officials of "dishonesty, hypocrisy and lack of transparency" in their approach to the city's saunas.
David Taylor, the former HIV and AIDS coordinator for Lothian Regional Council, HIV and AIDS coordinator in the 1980s, said licensing remained "crucial" as HIV continued to rise in Scotland.
Edinburgh Council voted on Monday to scrap the council regulation of the sex industry.
Mr Kilpatrick, who works with HIV patients, said: "Now there is a real concern that greater risks are going to be taken by women, and indeed their clients, to ensure they're able to make a living."
Councillor Gavin Barrie, convener of the committee that made the decision, said the council "will still take the safety and wellbeing of those working in saunas and massage premises extremely seriously".