Prime-time television has long reserved slots for HIV story lines—but usually in the emergency room or cemetery, with dark and dour medical plots (ER, House) that often seem dead on arrival. Set your remote, then, to the United Paramount Network (UPN) network, which has worked with its former parent company, Viacom, on the “Know HIV/AIDS” campaign. The initiative dared to spread awareness and prevention on UPN sitcoms—programs like Eve, Girlfriends and Half & Half, which feature mostly African-American characters for a largely African-American audience. This Monday, in fact, none other than Michelle Williams—we’re talking the Destiny’s Child Michelle, not the Dawson’s Creek/Brokeback Mountain Michelle—turned up on Half & Half, earning yuks for three weeks as an HIV positive record executive. But is HIV about to become undetectable on UPN?

On January 24, Warner Brothers and CBS announced that UPN is merging with the WB network, where HIV has been nearly invisible, to launch a new network called CW (it teams CBS & Warner Brothers) in September. Are the saucy sisters—and AIDS prevention messages—of Eve, Girlfriends and Half & Half doomed?

CW spokesperson Chris Ender, said, “It’s too early to talk specifics. UPN’s commitment too minority audiences and social issues covered in programs for young adults was one of the hallmarks of the network’s success. I expect that to continue, but I do not know what form it will take.” The new program lineup will be announced in May.

Though Williams’ Half & Half gig was her first sitcom experience, she felt her role helped UPN viewers see a different perspective on living with HIV. “I hope Naomi touches people and shows that no one should be afraid to love and care for someone who is infected,” She told POZ. “Also, for people to not be afraid to share their HIV/AIDS status, and not to be afraid to truly love.”

So why doesn’t HIV sit well on sitcoms? Thomas Dima, vice president of communications for cable television’s AIDS action group, Cable Positive, says, “It’s not an issue that’s easy to use in [comedy] unless you can handle it really well and still be educating.” He adds: “A lot of viewers are still ignorant about the issue, so it’s difficult.”

Because CW is half-owned by CBS, which, until recently was part of the Viacom family, Dima is not concerned about CW’s HIV programming. “I think that Viacom has shown a long history of being committed to HIV and AIDS, so I’m not worried about the merger.” Tune in tomorrow.