A private nursing home designed chiefly for the elderly has been approved by Maryland health officials to accept an AIDS patient -- and will be the first such facility to do so in Maryland and one of only a few in the United States.

Administrators at Seton Hill Manor, a 310-bed nursing facility near downtown Baltimore, and state health officials announced the unusual arrangement today in a joint news conference called also to debunk what officials said were myths about AIDS and its alleged contagion from casual contact with its victims.

Seton Hill administrators threw open the third floor of their facility to reporters and television camera crews for a view of the sparsely furnished room where the still unselected AIDS patient will live, presumably a bed- or chair-ridden patient with a life expectancy of about 60 days.

"Everyone should have equal access to health care," said Lorraine Raffel, Seton Hill's president and administrator. "AIDS patients must not become the lepers of the 1980s."

Raffel said she had met with both residents and staff of Seton Hill before making the decision to accept an AIDS patient. She said she found that after instructing the staff in special infection control procedures and explaining the unlikelihood of contagion, the staff accepted the idea.

"They were very supportive of our decision," she said. " . . . No patient or staff members decided to leave."

Seton Hill nursing aide Mattie Odom said her two daughters had expressed concern about her involvement with AIDS, telling her, "You better check this out before you get into it." But ultimately, "I was satisfied there was no risk for me at all," she said.

"The reaction of the residents is they seem to think it's all right," said Seton Hill Residents Council President George Smith. " . . . I don't feel worried about it."

AIDS, the acronym for acquired immune deficiency syndrome, is a condition that causes the body to lose its resistance to disease. Found most commonly in the United States among homosexual men and intravenous drug users, it leads to severe illnesses, such as pneumonia, and almost always results in death.

Reported cases of AIDS have been on the increase, causing increased alarm in the general population, and pressure has grown among public health policy makers to accommodate AIDS victims more than in the past.

Maryland Department of Health and Mental Hygiene figures show 193 reported cases of AIDS in the state since 1979, with more than 150 in the last 18 months. Of the total, 108 have died.

In response to the AIDS increase, health officials recently surveyed the state's 204 nursing homes, soliciting those that appeared best equipped for handling extended, post-hospital care of patients in the terminal stages of AIDS.

In addition to Seton Hill, four other nursing homes have indicated a willingness to take AIDS patients and of those, three are currently undergoing special training, officials said. They declined to name the facilities.

Nursing homes generally are prohibited from accepting patients with communicable diseases, such as hepatitis or AIDS, but can obtain waivers by applying special state-required infection control measures.

Raffel said the AIDS patient at Seton Hill will not be purposely segregated from the rest of the nursing home, but since he is likely to be bed- or chair-ridden, he is not expected to circulate through the facility.

Initially, staff members will wear gowns and gloves when attending the patient, she said, and his laundry will be washed separately. His cups, plates and other eating implements, like those of the other patients, will be made of disposable plastic and thrown away after use, Raffel said.

Raffel said she may accept one or two more AIDS patients if they apply.

Officials of AIDS clinics and research centers throughout the country applauded the state-sanctioned AIDS program.

"I think it's wonderful that Maryland is taking the lead in this," said Caitlin Ryan, manager of the AIDS education fund at the Whitman Walker Clinic in the District.

Ryan, as well as AIDS clinic officials in San Francisco and New York, where there are large homosexual populations, said they are aware of only a few other private nursing homes that have accepted AIDS patients.

Thomas Krajewski, assistant secretary for health in the state Department of Health and Mental Hygiene, said studies by the Communicable Disease Centers in Atlanta show that hundreds of care providers and family members in close touch with AIDS victims have failed to develop AIDS themselves.

"No casual contact causes AIDS," Krajewski said. "That's the unwarranted fear . . . . Even significant contact" will not cause AIDS to spread.

Krajewski and other officials said that AIDS is transmitted principally through sexual contact or exchanges of blood or other bodily fluids through intravenous needles used by AIDS victims.