“It’s essentially an anatomic vaccine for life.”

AIDS RESEARCH

Male Circumcision Thwarts HIV Infection

5 AUGUST 2005 VOL 309 SCIENCE www.sciencemag.org

A study in South Africa has shown for the
first time that circumcising adult men can
dramatically lower their risk of becoming
infected by HIV through heterosexual sex. “It
is a major advance in HIV-prevention studies,”
said Catherine Hankins, an associate
director at the Joint United Nations Programme
on HIV/AIDS (UNAIDS).

For nearly 20 years, observational studies
have suggested that circumcision protects men
from HIV infection, but until now, there was no
prospective evidence to support that conclusion.
The new study, led by clinician Bertran
Auvert of the University of Versailles in Saint-
Quentin, France, began in August 2003 with
more than 3000 uncircumcised men between
18 and 24 years old from the Orange Farm
Township near Johannesburg. Half the participants
were circumcised at the trial’s outset. As
Auvert reported last week at an international
AIDS meeting in Rio de Janeiro, the study was
stopped early, in November 2004, after an
interim analysis showed that “the protection
effect of male circumcision was so
high that it would have been unethical
to continue.”

The study, performed in collaboration
with Adrian Puren of
South Africa’s National Institute
for Communicable Diseases and
funded by France’s Agence
Nationale de Recherches sur le
SIDA (ANRS), suggests that circumcision
can offer 65% protection
from infection. Only 18 men
in the circumcised group acquired
new HIV infections, as opposed to
51 in the uncircumcised group.
Further bolstering the results, men
in the circumcised group reported
18% more sexual contacts than
controls. “It’s extremely exciting,”
says King Holmes, an expert in
sexually transmitted diseases at
the University of Washington,
Seattle. “It’s essentially an
anatomic vaccine for life.”

Circumcision could profoundly
curtail the spread of HIV in sub-
Saharan Africa. Circumcision
practices vary greatly from country to country,
and studies have shown that the regions with
the worst AIDS epidemics have the lowest circumcision
rates.