Federal funding for AIDS research has tripled since last year as efforts to understand and treat the mysterious and often-fatal ailment continue to be a top public-health priority, government health officials said yesterday.

In testimony before a congressional subcommittee investigating the federal response to the epidemic of AIDS, for acquired immune deficiency syndrome, Dr. Edward N. Brandt Jr., assistant secretary for health, said research efforts "are on course and continuing."

"I was hopeful that by the end of this year we would have the AIDS agent isolated and developed a vaccine for it," Brandt said. "But everything we discover about this complex disease leads us to more questions.

"From the standpoint of the people who are suffering, things haven't been moving fast enough--and that I deeply regret."

The federal Centers for Disease Control in Atlanta continues to receive five to seven new AIDS cases a day, a spokesman said. The disorder, which primarily strikes homosexual men and intravenous-drug abusers, destroys the body's immune system and leaves victims vulnerable to fatal infection.

As of July 26, CDC reported, 1,922 people had contracted the syndrome and 743 have died.

Brandt also announced the award of a major AIDS research contract to a New York hospital and two new AIDS-related research initiatives.

The three-year, $1.7 million contract will support the development of a blood test to identify AIDS patients and conduct research on the possibility that the disease is transmitted by blood transfusions. It was awarded to the Memorial Sloan-Kettering Cancer Center and the New York Blood Center and will be funded through the National Institute of Allergy and Infectious Diseases.

"The goal of this initiative is to permit blood collection agencies to screen blood, not donors," Brandt said.

Successful development of a blood test for AIDS would identify carriers and help protect the nation's blood supply from contamination by the still-unknown AIDS agent.

The Public Health Service spent $5.5 million on AIDS in 1982 and will spend $14.5 million in 1983. An additional $12 million for AIDS research through the end of this year and part of 1984 was approved in the recently signed supplemental appropriations bill, Brandt said.

Stanley J. Matek, immediate past president of the American Public Health Association, told the House Government Operations subcommittee on intergovernmental relations and human resources that federal health agencies "have done what they could with the resources available to them," but he said the agencies are "underfunded, understaffed and overworked."