Two new studies have raised concerns about the current perceptions of HIV spread.

A first study has raised doubts about earlier research which appeared to indicate the possibility that circumcision among men, which reduces their risk of infection from the AIDS virus, could also benefit their female sexual partners.

Findings of the study, reported at the 15th Conference on Retroviruses and Opportunistic Infections, showed that male circumcision conferred no indirect benefit to the female partners. Furthermore, circumcision increased the risk if the couples resumed sex before the wound was fully healed, usually in about a month.

The study was conducted by Maria Wawer of Johns Hopkins University and colleagues on 1,015 HIV-positive men who were chosen at random to be circumcised either immediately or after waiting two years. Also, rates of condom use, bacterial vaginal infections, vaginal discharge, painful urination and urinary tract infections remained the same among women.

Another study by Seattle scientists has found that use of the drug acyclovir to treat people with genital herpes did not lower their risk of contracting HIV, as it was hoped previously. "We were surprised and disappointed," said Dr. Connie Celum, the University of Washington researcher who led the study. The scientists looked at more than 3,000 herpes-infected people on three continents. The trial was double-blind, which produces the most accurate results.

Last month, the US Food And Drug Administration has approved etravirine tablets for the treatment of HIV patients. Etravirine, which will be sold under the trade name Intelence, was developed by Tibotec Pharmaceuticals, Ltd. The drug is a non-nucleoside reverse transcriptase inhibitor (NNRTI) that helps to block an enzyme which HIV needs to multiply and it was approved to be used in combination with other anti-HIV medications. Development of etravirine was triggered by the observations of in vitro anti-HIV activity of etravirine against mutant, NNRTI-resistant HIV strains.

According to latest statistics released by WHO, 33 million people around the world are diagnosed to be living with HIV. The number seemed to have leveled off from 40 million worldwide which sounds promising but it still is a matter of great concern. Another 2.5 million people contracted the virus this year, which means a 40 percent lower than the estimate for 2006. Two million people more have died from AIDS in 2007.