Fewer needle drug users in the U.S. are testing positive for HIV, reported the Associated Press. Health officials said the rate has dropped by half since the 1990s and that the decline may be related to a growth in needle exchange programs.
The U.S. Centers for Disease Control and Prevention released the study, according to USA Today. More than 10,000 drug users in 20 metropolitan areas were surveyed and tested for HIV in 2009. About 1 in 10 tested positive for the virus. In the 1990s, roughly 1 in 5 tested positive.
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USA Today also reported the number of needle exchange programs has grown, from nearly 70 in the mid-1990s to more than 180 in 2008.
"Despite the fact that we've seen declines in new HIV infections, a substantial number of IDUs (injection drug users) in major U.S. cities are HIV-infected and their risk behavior remains fairly high," said Dr. Cyprian Wejnert, an epidemiologist who ran the study, to Reuters.
"We found 9% of IDUs were HIV-positive and nearly half of those were unaware of their infection," Wejnert told the news wire.
The number of injection drug users tested each year for HIV has dropped from 66% in 2006 to 49% in 2009, according to USA Today.
Reuters also reported that the study found about one third of injection drug users in the survey said they shared syringes, most said they had unprotected sex in the past year and more than half said they had more than one sexual partner.