THURSDAY, Oct. 17 (HealthDay News) -- HIV-negative heterosexuals
who take drugs that protect them from contracting the AIDS virus
from their HIV-positive partners don't engage in more risky sexual
behaviors, according to a new study.
Researchers from the University of Washington in Seattle found
that knowing they are protected against HIV transmission doesn't
change how these people behave sexually or lead them to have sex
without a condom more often.
The study is published in the Oct. 16 issue of the journal
The Lancet Infectious Diseases.
"Evidence for the effectiveness of new HIV-prevention
strategies, including pre-exposure prophylaxis, has spurred
optimism that the global HIV epidemic might be reversed," Dr. Jared
Baeten said in a journal news release. "However, an important
question is whether HIV-negative partners who know they're
protected by prophylaxis will compensate for this by increasing
their sexual risk-taking, such as through increasing their levels
of unprotected sex."
In conducting the study, an international team of researchers
led by Baeten examined findings from the 2011 Partners PrEP study,
which revealed that a preventive drug regimen could protect
HIV-negative men and women from contracting the virus from their
The researchers examined information on more than 3,000 people
for up to one year before and after taking drugs to prevent the
transmission of HIV, the virus that causes AIDS. The participants
were counseled on pregnancy testing and how to reduce their risk
for sexually transmitted infections, such as gonorrhea, chlamydia,
Even before the participants learned the results of the
research, which established the protective effects of the drugs,
they were engaging in unprotected sex less often, the study authors
found. The researchers concluded that the risk counseling the
participants had received may have been effective.
After the participants knew the drugs they were taking were
shown to provide protection against HIV transmission, the
investigators found no significant difference in the level of
unprotected sex taking place between partners.
There was, however, a slight increase in the frequency of
unprotected sex outside the relationship. The researchers said
there was no increase in rates of sexually transmitted infections
"The results provide encouraging evidence that behavioral
changes as a result of pre-exposure prophylaxis might not undermine
its strong HIV prevention and public-health benefits," Baeten
The U.S. Centers for Disease Control and Prevention has more