Davis did so without disclosing he had HIV, police said.
Investigators are concerned that there may be other persons, over a period of years, who have interacted sexually with Davis who also may be victims.
The Center for Disease Control and Prevention says there is little to no risk of contracting HIV from oral sex.
But under Ohio Revised Code, it is illegal for people to engage in sexual conduct if they have tested positive for HIV and do not tell the other party.
Violators can face charges of felonious assault.
The Dayton Police Department is encouraging people who engaged in sex acts with Davis to seek testing immediately, and contact Maj. Brian Johns, division commander of Investigations & Administrative Services at 937-333-1110 so circumstances can by fully investigated.