In the week since his headline-making revelation on Oprah: Where Are They Now? that he’s been HIV positive for 12 years, Who’s the Boss? star Danny Pintauro has been working to become an AIDS and HIV activist for those struggling with the same secret. In his first exclusive sit-down interview with his husband of one year, Wil Tabares, Pintauro, 39, opened up about how he contracted the virus. 

“Believe it or not, with this guy I was actually safe. We did use condoms,” Pintauro, who played Jonathan on Who’s the Boss? from 1984 to 1992, tells Us in his exclusive interview. “I got it another way, which was through oral sex. When you put all of these nasty things together, like a compromised immune system, having been up for a long time, drugs, rough sex, all of that combined with lesions in your mouth, bodily fluids, it’s that easy.”

During his same interview with Oprah, Pintauro revealed he was previously addicted to crystal meth. He contracted HIV around the same time he was struggling with substance abuse. 

Though he did not name his sexual partner to Us, Pintauro admitted that he had forgotten the man’s name until one day he happened upon it in an email. Since then he’s been trying to locate him. 

“I have searched. I searched the obituaries because I had a fear that I’d find him there, and I can’t find him. So we’re going to keep doing it,” Pintauro says as Tabares nods. (Us Weekly broke the news of both Pintauro’s engagement and April 2014 wedding to Tabares.) “Mostly I just want to find out if he’s okay. The lifestyle he was leading was really irresponsible and I just want to see if he survived.”

After making his announcement on Oprah, Pintauro kicked off his Beacon of Light Tour to spread awareness about HIV and the dangers of crystal meth use and participating in HIV Equal Campaign, which aims to eliminate HIV stigma.

Watch the clip now to see which Who’s the Boss? costar was left out of the loop on Pintauro’s HIV confession and how he first told his husband. 

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