Scientists are struggling for over two decades to find a cure for AIDS, but what they have achieved till now rather seems to work against the stopping of the epidemics.

A research team from Ohio University found that about 38 % of HIV-infected sexually active older adults practice unprotected sex, a risky behavior that spreads further the infection. The research made on a pool of 260 HIV-positive older adults revealed that those sexually active were mostly males, used Viagra and were engaged in a relationship.

In 2003 there were 90,000 cases of AIDS patients, over 50 in US (out of a total of about 438,000 cases). But by 2015 they will account for 50 % of all HIV/AIDS cases in the US as new medication has prolonged the lifespan of the HIV-infected ones. Moreover, Viagra and other similar drugs have also prolonged the sex life of older adults: up to 65 % of males, aged 60 to 71, have sex! But amongst HIV-positive older adults, 38 % were found to be sexually active.

"Those who are more likely to engage in riskier behavior - for example, those who are using drugs - are more likely to have unprotected sex," said lead author graduate student Travis Lovejoy.

"What we don't know yet is whether these individuals are in a monogamous relationship with someone else who is HIV positive and believe there is no risk of infection."

The categories of HIV-positive males more predisposed to practice sex were the older ones without cognitive impairment, younger ones and those who perceived their overall health as good. Due to the decreased percentage of older sexually active HIV-adults, those practicing unprotected sex represent just 13 % of their overall. But as 38 % of the all sexually active patients have unprotected sex, prevention efforts must target intensively this category.