BOSTON, JULY 15 -- -- A study of military recruits found that equal numbers of men and women were infected by AIDS in some areas of the United States and that twice as many blacks as whites carry the virus, the New England Journal of Medicine reported today.

Judging by blood tests of recruits conducted from October 1985 through March 1986, the researchers said the AIDS epidemic is apparently no longer primarily restricted to male homosexuals and intravenous drug users, as it was when the virus was first recognized.

The researchers said the incidence of the disease was highest in densely populated urban areas, where a high proportion of the population is often black. The regions of the country found to have the highest rates of infection, and where roughly equal numbers of men and women were infected, included New York City, particularly the Bronx, San Francisco, Washington, D.C., and Essex County, N.J.

The study found that nationwide 1.65 of every 1,000 military applicants tested positive for the disease compared to 0.61 of every 1,000 women. But 20.3 of every 1,000 male applicants and 17.4 of every 1,000 female applicants from New York City tested positive for the AIDS virus. In San Francisco, 11 out of every 1,000 men and 10.9 out of every 1,000 women had been exposed to the disease. Of the applicants from Washington, 10.7 of every 1,000 men and 7.3 of every 1,000 women were infected.

The researchers said that 3.89 of every 1,000 black applicants overall tested positive for the virus compared to 0.88 of every 1,000 whites.