Sabrina Heard, 55, who is HIV positive and works as community health worker at the Women's Collective in Washington, administers an HIV test in September. (Nikki Kahn/The Washington Post)

The HIV infection rate for heterosexual African American women in the District’s poorest neighborhoods nearly doubled in two years, from 6.3 percent to 12.1 percent, according to a study released Wednesday by the D.C. Department of Health.

The large increase reflects wider testing of people who were previously unaware of their status and possibly a still-rising rate of new infections in that high-risk group, officials said.

The disease remains at epidemic levels in Washington. In releasing the study, District health officials announced new recommendations for doctors and other health-care providers to start treatment immediately for all people newly diagnosed with HIV instead of waiting for evidence that someone’s immune system has been severely damaged.

Washington is preparing to host the International AIDS Conference next month, the first time the global gathering is returning to the United States in more than two decades. District officials are seeking to highlight the city’s progress in fighting the epidemic.

On Wednesday, officials also released the Health Department’s annual update on HIV/AIDS, which showed a drop in the overall number of new AIDS cases over four years and improvements in getting infected people into care quickly. For example, 76.1 percent of infected people were connected with care within three months of diagnosis in 2010, up from 58 percent in 2006.

The D.C. Department of Health reports an increase in the percentage of heterosexual residents testing HIV positive, especially among women. (The Washington Post/Source: D.C. Department of Health)

Mayor Vincent C. Gray (D), in a statement, cited that quick connection to care as one of the city’s many achievements.

The annual snapshot also gives a more accurate picture than in previous reports for the number of people living with HIV or AIDS because of an improved tracking system that eliminates duplication. There were 14,465 people, or about 2.7 percent of District residents older than 12, who were living with HIV or AIDS in 2010, the year covered in the report. That prevalence rate — the total percentage of people in a population with the condition or disease at a given time — is among the highest for any U.S. city.

More troubling were the data about infection rates of heterosexuals living in HIV-prevalent, low-income parts of the District, predominantly wards 7 and 8. The District is one of 21 cities in an ongoing survey funded by the U.S. Centers for Disease Control and Prevention of behavior in three target populations: heterosexuals at high risk of HIV infection, men who have sex with men and injection drug users.

In 2008, the survey sampled 750 heterosexuals in areas with high infection rates and poverty and found an overall infection rate of 5.2 percent among that group and a 6.3 percent infection rate among those at-risk women.

By 2010, those rates had climbed to 8 percent and 12.1 percent, respectively. The demographics of the 482-participant study were similar to 2008: nearly all black, 62 percent making less than $10,000 and 37 percent unemployed.

The survey interviewed individuals with connections to high-risk social networks. In those social networks, HIV infection is high and chances of getting infected are greater, officials said.

Greg Pappas, senior director at the D.C. Health Department, said it was difficult to know whether the increase represents new infections. The sample size is also limited, he said.

Nevertheless, he said, “We continue to have a very serious heterosexual epidemic.”

Unlike other cities where the at-risk population might be concentrated among intravenous drug users or men who have sex with men, Washington has a very “mixed epidemic,” with a huge burden falling on heterosexual African Americans. Officials said 90 percent of all women with HIV are black. Pappas estimated that 20 percent to 30 percent of the District’s HIV-positive population “is probably walking around infected and don’t know it,” he said.

Other experts said the findings of the study were worrying.

“While recognizing the limitations of a sample-based study, it seems the HIV epidemic among heterosexuals may be more significant than the previous study estimated,” said Michael Rhein, senior vice president at the Institute for Public Health Innovation, a nonprofit group that coordinates several regional programs supporting people with HIV/AIDS.

He called the new rates alarming. In the worst scenario, he said, they reflect “a true increase in the HIV rate among heterosexuals and women living in areas of concentrated poverty.”

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