The federal government yesterday revealed research showing that many female prostitutes are carriers of acquired immune deficiency syndrome, and it warned men to avoid prostitutes if they want to protect themselves from the AIDS virus.

In the newest and most definitive results to date of AIDS surveys among prostitutes, a Centers for Disease Control report to be issued today shows that five of 92 prostitutes tested in Seattle and 10 of 25 prostitutes who came forward for tests in Miami were carrying the AIDS virus. The presence of the disease was detected through blood tests.

The levels among prostitutes are far above the rates at which others in society are infected with the AIDS virus. Based on CDC estimates, one in 300 or 400 Americans might show signs of infection with the AIDS virus.

Government health officials at a news conference yesterday emphasized repeatedly that AIDS is not passed by casual contact, that it is a sexually transmitted disease and therefore can be avoided by curbing certain sex practices.

Also released were new figures showing that 133 heterosexual women and men are now classified as having AIDS. This represents about 1 percent of the 13,061 adult AIDS cases.

Although that proportion has remained constant since heterosexual cases were first counted in 1984, the number of cases has grown as the AIDS epidemic has worsened.

The new cases are nearly triple the number of a year ago, when there were 45 heterosexuals with AIDS.

Another 6 percent, about 780 of current AIDS cases, do not fit any risk group and may include more cases of heterosexual transmission of the disease.

"We never felt this disease was a homosexual or gay disease," said Dr. Anthony Fauci, the National Institutes of Health's chief AIDS researcher. He emphasized that sexual intercourse is the main way AIDS is transmitted and that certain sexual practices of some homosexuals prompted a greater number of cases among that population.

But, in another new result offered yesterday, officials confirmed that three health workers were found to have positive blood tests, even though they are not in any AIDS risk group. They apparently were infected by needles used in lab work. One worker is from Boston and another is from New York, according to Public Health Service spokeswoman Shellie Lengel.

Lengel said a paper is being readied for publication next week on the cases, but no other information is available. Another 15 health workers found to be positive do belong to some risk group, according to federal reports.

Officials urged all those handling needles, such as health care workers and embalmers, to observe federal precautions, issued in 1983, on handling needles and fluids contaminated with AIDS.

Federal health directors attempted to calm worries about heterosexual transmission by saying that if the public followed safe sex guidelines, "this could stop transmission of this disease today," according to Dr. James Mason, acting assistant secretary of health.

"This disease is controllable now," Mason said, adding that recent declines in cases of syphilis and gonorrhea show the public is modifying its sexual behavior because of fear of contracting AIDS.

The government yesterday issued the following guidelines on reducing the risk of contracting AIDS:

*Sex with members of AIDS risk groups or with people who have sex with risk-group members should be avoided.

*Condoms should be used if such sexual encounters occur, the health officials said.

*The injection of illicit drugs should be avoided. Needles should not be shared.

*Women who abuse drugs, have a partner in a high-risk group or whose blood is positive for the AIDS virus should avoid pregnancy, the guidelines state.

If they become pregnant, they should not breastfeed their babies, federal doctors said yesterday.

Although not part of the guidelines, the doctors said the recent case of an Australian infant who developed AIDS through his mother's milk should discourage breastfeeding by women whose blood is shown to be positive for the AIDS virus.

The doctors played down the risk of contracting AIDS from saliva and tears, noting that the AIDS virus only occasionally appeared in these body fluids of AIDS patients. Dowdle added, "You might find virus in the saliva of one out of 50 people with AIDS."

This information should lessen the public's fear about contracting AIDS through casual kissing or being sneezed or coughed on by people with AIDS, the doctors said.

"It takes the most intimate kind of body exchange to get it," said Mason. "If you look at the data that has accumulated with families, clearly hugging, kissing and other forms of affection exclusive of sexual contact" does not result in a risk of AIDS.

The doctors said they did not fault parents for keeping children home rather than sending them to a school attended by children with AIDS, yet they noted the risk from a "normal" child with AIDS was minimal.

"Parents want a 100 percent guarantee and we can't give it to them," said Fauci. "But we've bent over backwards on our guidelines to be conservative. People need to understand this is a sexually transmitted disease."