The suit was filed in a Los Angeles court on Monday, accusing the R&B star – who has not yet responded to a request for comment – of sexual battery, fraud, infliction of emotional distress and negligence.

Two of the three accusers have chosen to remain anonymous, while Quantasia Sharpton chose to go public at a press conference in New York on Monday.

Ms Sharpton claimed Usher had failed to warn her about STDs when she was “selected to go backstage after the show”.

“It was my birthday so I was wearing a birthday crown,” she said.

“That is why I was selected to go backstage after the show. Later, a security guard picked me up and asked me for my number. He told me Usher had seen me backstage and was interested in me.”

Ms Sharpton claimed Usher called her on her cellphone and went to visit her in her hotel room.

“When I first heard he had herpes I couldn’t believe it. I would have never consented if I had known,” she said.

In Monday’s case, only one of the three accusers tested positive for herpes. Ms Sharpton did not.

“We hope the reports are not true,” her lawyer said.

“We hope that Mr Raymond (Usher) tests negative for herpes, and that this can all be cleared up quickly,” she added.

“We hope that he has not knowingly endangered his sex partners, fans who revered him and who were thrilled to receive his personal attention.”