A new study will focus on AIDS infections among heterosexual men and women in an effort to learn more about control of the fatal disease in a high-risk, sexually active population, federal health officials announced Thursday.

The National Institute of Allergy and Infectious Diseases said the study is to be conducted among 2,000 heterosexuals in Newark, N.J., and Brooklyn, N.Y., over a five-year period.Dr. Anthony S. Fauci, director of the institute, said the purpose of the study is to develop more effective strategies for the prevention and treatment of AIDS, or acquired immune deficiency syndrome, in a population that is not homosexual or using intravenous drugs.

Only about four percent of the adult AIDS cases can be traced to heterosexual contact, but such sexual conduct accounts for 30 percent of all AIDS cases among women, the NIAID said.

The study will concentrate on heterosexuals with a history of what is considered to be high-risk behavior for contracting AIDS.

The factors include:

-An average of 10 or more sex partners a year.

-A history of sexually transmitted disease within the last five years.

-Sexual contact with persons, such as homosexuals or intravenous drug users, who are considered to be at high risk for AIDS.

-Those infected or exposed to fungal, viral, retroviral, bacterial or parasitic infections that are thought to increase the risk of acquiring AIDS.

Intravenous drug users, a group with one of the highest rates of AIDS infection, are excluded from the study.

Newark and Brooklyn were selected for the study, the NIAID said, "because they are located in inner-city areas populated by large numbers of HIV-infected drug users, a potential reservoir of infectivity for heterosexuals."