One of three people suing R&B singer Usher Raymond spoke out at a New York news conference Monday morning, saying Raymond had exposed her to genital herpes.

Quantasia Sharpton appeared with celebrity attorney Lisa Bloom at the New York Hilton and described an encounter with the singer in a hotel room while celebrating her 19th birthday two years ago. She says she was wearing a crown at an Usher concert when she and her friends were singled out and brought backstage.

Sharpton did not indicate what city or exactly when the concert took place.

"We spoke for awhile, and then we engaged in sexual contact," Sharpton said. "He never warned me about any STDs."

She says she never heard from Raymond again after the encounter.

"When I first heard reports that he had herpes, I couldn't believe it. I had a child a year ago, and I knew I was negative," Sharpton said in the news conference. "But I contacted Lisa Bloom to find out what my rights are as a woman. Although I am negative, I am upset by the reports, because I never would have consented, if I would have known. I would not have taken a risk of getting an incurable disease."

After Sharpton's remarks, Bloom stepped to the podium and began a statement, pointing out that herpes is an incurable disease, and that Raymond has not publicly denied reports that he was diagnosed with the disease in 2009. She also said he has not denied reports of an alleged $1.1 million payout in 2012 as a settlement for a woman in connection with reports of an alleged infection.

Bloom did not identify the other two people -- one woman and one man -- who are party to the lawsuit filed Monday, choosing to identify them only as "Jane Doe" and "John Doe."

"At least one of my clients has tested positive for the virus and alleges that it was Mr. Raymond who transmitted it. But if Mr. Raymond is negative, by allowing this story to go on unrebutted for weeks on end, he has caused many people to be concerned about their reproductive health," Bloom said. "By filing this lawsuit, we seek to ascertain the truth. We hope the reports are not true. We hope Mr. Raymond is negative, and this can all be cleared up quickly."

Bloom says her firm is reviewing other potential accusations against the singer and additional names may be added to the lawsuit in the coming days. As of this point, Raymond's representatives have not responded to requests for comment.

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