Researchers from
the Unviersity of California, San Francisco, report in
the journal Clinical Infectious Diseases that
postexposure prophylaxis to prevent HIV infection after
nonoccupational exposure to the virus is not 100%
effective. The researchers followed 702 HIV-negative
adults who received a four-week regimen of antiretroviral
drugs after being exposed to the virus through unprotected
sex or shared needles. At 12 weeks after PEP was
completed, seven of the study subjects--about
1%--had been infected with HIV. Of those seven, three
had no other possible exposures to the virus during
the follow-up period and were determined to have been
infected despite PEP; it was unclear whether the other
four were infected before or after PEP was administered.
The researchers
note that anti-HIV drugs given after occupational
exposures to HIV--usually through accidental
"needle-stick" injuries to health care
workers--also is not 100% effective in preventing HIV
from taking hold in the body. Because occupational and
nonoccupational PEP therapy is not a guarantee
against HIV infection, primary HIV prevention
practices remain essential, the study authors say.
(Advocate.com)