The news broke yesterday that Charlie Sheen is HIV positive, but it's something that he's reportedly known about for years -- along with a number of those close to him, including ex-wife Denise Richards and industry execs.

Sheen has been taking antiretrovirals and according to a source for People, "He is saying there is virtually no trace of HIV in his blood. He is telling people the virus is now undetectable."

Sheen will appear on Today this morning to chat with Matt Lauer about the news. "He's still HIV-positive. But he isn't about to slow down," the source added.

While there have been reports that Sheen has slept with women since learning he has HIV without telling them, Sheen's former girlfriend Natalie Kenly said she does NOT believe he'd be recklessly promiscuous. "He has regard for human beings and cares about people. I do not see him knowingly putting women at risk," she told the mag.