Not many prevention strategies for HIV infected people exist in sub-Saharan Africa because health authorities pay heed to risks related to casual-sexual encounters. HIV continues to effect long-term couples relationships in sub-Saharan Africa, especially young people.

Scientists presenting research at the 17th Conference on Retroviruses and Opportunistic Infections, the annual mid-winter AIDS meeting in the United States, reported these findings.

Epidemiologist Rebecca Bunnell of the Centers for Disease Control and Prevention, who worked in Uganda and Kenya for 14 years said, it is tragic to see that HIV transmission in couples has not been recognised much.

She added, "It undoubtedly has resulted in millions of deaths and has produced millions of orphans."

It was reported that in Kenya, HIV affects about one in 10 couples.

About 16000 Kenyans gave their blood samples that were assessed in 2007. they were aged between 15 and 64 and it was seen that only 15 per cent of infected people knew they were infected by the virus.

Wafaa El-Sadr, an AIDS researcher at Columbia University who helps run prevention programs in 14 African countries said, "The message has to be very carefully crafted. You want to encourage people to come as couples, but you never want to turn anybody away just because they come alone."