SAN FRANCISCO (AP) _ Four federal hospitals have ignored a recommendation that they notify thousands of people who may have received AIDS-infected blood over a seven- year period, a newspaper reported today.

The hospitals received most of their blood from a San Francisco blood bank whose volunteer donations were among the most contaminated in the country in the years before AIDS blood screening tests were established, the San Francisco Chronicle said.

The federal Centers for Disease Control in Atlanta recommended last March that hospitals contact recipients of blood transfusions from 1978 to the spring of 1985, when AIDS antibody screening became widely available.

The Chronicle said its survey found the recommendation disregarded by Letterman Army Medical Center and the Veterans Administration Hospital in San Francisco, the Oakland Naval Hospital and David Grant U.S. Air Force Medical Center in Fairfield.

Three of the hospitals cited difficulty in contacting former patients. The the VA Hospital said such a program would probably locate few AIDS-infected patients.

CDC epidemiologist Scott Holmberg said the federal center made its recommendation after it concluded that several thousand patients had been infected with AIDS through transfusions and are unaware of their infection.

The agency's advice was particularly aimed at areas such as San Francisco, where the Irwin Memorial Blood Bank - source of much of the four hospitals' blood - drew about 5 percent of its blood from homosexual male volunteers from 1978 to 1982.

Irwin officials acknowledge that 83 people contracted AIDS after receiving transfusions of Irwin blood collected before the AIDS antibody test was available.

About 8,400 patients at Letterman Army Medical Center, 6,500 at Oakland Naval Hospital, 4,000 at David Grant Medical Center and up to 3,000 at the VA Hospital in San Francisco received transfusions during the period in question, the Chronicle said.