Heterosexuals : AIDS Risk for Women, Young Rises

Younger people and women increasingly are being infected with the AIDS virus, according to blood test results on more than 300,000 civilians who applied for military service, researchers said in a report published in today’s New England Journal of Medicine.

The results, they said, suggest that heterosexual transmission of the deadly virus may “already have emerged as an important mode of HIV infections in some regions of the United States.” The AIDS virus is commonly referred to by its acronym, which stands for human immunodeficiency virus.

Overall, the report said, 1.5 per 1,000 of the 306,061 applicants tested between October, 1985, and March, 1986, were found to be infected, with four times as many blacks as whites carrying the virus. Males were about 2 1/2 times more likely than females to be infected, according to the researchers, Dr. Donald S. Burke and colleagues from Walter Reed Army Research Institute.

Higher in Six Areas

But in six geographic areas identified by the study, 10 or more per 1,000 applicants were infected, and the male-to-female ratio was almost equal. The six localities are Washington, D.C., San Francisco, Essex County, N.J., and three New York City boroughs--Manhattan, the Bronx and Brooklyn.

In eight other regions, where the infection rate ranged from 5 to 10 per 1,000, three times as many males as females were infected. Six of the eight counties were in the Washington-Baltimore and the New York-Newark area. The remaining two were San Mateo County in California and Travis, Tex.

The only other national estimate of the infection rate based on large-scale testing involves civilian blood donors. That rate is 0.4 per 1,000 people. However, the military investigators pointed out that people at high risk of carrying the AIDS virus--homosexuals and intravenous drug users--are vigorously discouraged from donating blood. Therefore, they surmise, this tends to result in an underestimation of the actual infection rate.

Precisely because of such uncertainty, federal health officials are planning to test a scientifically selected cross-section of the U.S. population in order to establish a more accurate estimate of the national infection rate. The results are expected next year.

Although the Walter Reed scientists admitted that an “appreciable fraction” of the infected military applicants may have been homosexuals or intravenous drug users, the finding that the infection rate in some geographic locations was as great for females as for males indicates that females may represent a growing percentage of AIDS cases in the future.

The researchers pointed out that the number of people exposed to the AIDS virus reflects the extent of the epidemic several years in the future. They said their figures indicating that infected individuals are increasingly female supports the view that heterosexuals are taking a greater role in spreading AIDS.

About 20 of every 1,000 male and 17 of every 1,000 female applicants from New York City tested positive for the virus, according to the study. In San Francisco, the rate was 11 per 1,000 for males and 10.9 for women. Nationally, 3.89 of every 1,000 blacks tested positive for the virus compared to 0.88 of every 1,000 whites. For Latinos, the rate was 1.07.