Poverty, unemployment and other socioeconomic factors are helping to fuel a growing HIV problem among black women, a U.S. study released on Thursday suggests.

Black men and women account for a majority of the estimated 40,000 new HIV infections that are diagnosed in the United States each year. The new HIV infection rate among black women is about 18 times that of white women.

The study published by the Centers for Disease Control and Prevention found that black women infected with the AIDS virus are more likely to be unemployed and willing to trade sex for drugs or money than uninfected black women.

The study was based on a small group of black women in North Carolina who were diagnosed with HIV in 2003 and the first half of 2004 and a larger group of uninfected women who were recruited at HIV testing sites in 2004.

It found that 71 percent of those who were infected did not have a job, compared with 38 percent of those uninfected.

More than a third of the HIV-positive women admitted trading sex for money, drugs or other gifts, reported researchers with the Atlanta-based CDC, North Carolina Department of Health and University of North Carolina.

Only 15 percent of uninfected women had done so.

There was also a higher tendency for the infected women to be on welfare or some other form of public assistance.

“It suggests that it’s a lot more difficult for women who are poor to even think of HIV as a health priority when there are so many other issues that they are dealing with,” said Dr. Lisa Fitzpatrick, director of the CDC’s minority HIV/AIDS research initiative and one of the study’s authors.

Fitzpatrick noted that black women in North Carolina had an HIV infection rate 14 times higher than white women. “I think this mirrors a lot of the epidemic in the rest of the country. This is not unique to North Carolina.”

Only heterosexually active black women between the ages of 18 and 40 living in parts of the state with the highest AIDS death rates were included in the study. Those who admitted injecting drugs were excluded.

Researchers also found worrying similarities in sexual behavior among the two groups of women, including high rates of sexually transmitted diseases.

The majority of both groups, however, felt that they were unlikely or very unlikely to contract HIV.