The Colorado Board of Health -- in what appears to be the first such action in the country -- has decided to start keeping track of individuals who have been exposed to the AIDS virus but show no symptoms of the disease.

The department plans to require laboratories and doctors to report to state health authorities on a confidential basis the names and addresses of individuals who have taken a blood test that shows they carry antibodies to the AIDS virus. Officials said they will use the information to help counsel those who carry the antibodies.

While Colorado state health officers argue that such information is vital to help slow the spread of AIDS, critics are concerned about privacy questions and the potential that the test results could be used for discriminatory purposes, particularly because AIDS strikes homosexual men and intravenous drug users in greatest numbers.

The federal Centers for Disease Control keeps track only of actual AIDS cases, which now number more than 12,000 in the United States, including 114 in Colorado.

While some federal and state health officials said Colorado's action was precipitous, officials with the Association of State and Territorial Health Officials, the group representing state health departments, predicted that other states would follow Colorado's lead.

"I think they are a little ahead of the rest of us. As more has been learned that people who test positive [on the AIDS antibody blood test] may well be infectious, capable of infecting other people, it does seem like we're going to want to make sure that anybody who tests positive has accurate information about the infection, the means of transmission," said Kristine Gebbie, administrator of the Oregon health division and past president of that state's health officials group.

A draft document prepared for the group tacitly supports reporting regulations for positive AIDS antibody blood-test results "when the means exist to protect and utilize the information for disease transmission control."

"More of the states are talking about it. Colorado just got their plan organized ahead of the rest of us," Gebbie said. "I feel comfortable that we can do that without violating anyone's privacy."

The blood test, approved in March by the federal Food and Drug Administration, is not a test for AIDS, acquired immune deficiency syndrome. It tests for antibodies -- the body's defense cells -- and when it is positive it shows only that a person has at some time been infected with the AIDS virus. The test is given in blood donation centers and is also available in alternative testing sites, from health departments and clinics to doctors' offices, for those at risk who want to find out if they have been exposed to the AIDS virus.

Experts who initially worried about the accuracy of the test now say it has been shown to be highly accurate in picking up exposure to the AIDS virus. It is thought that from 5 percent to l0 percent of people who are exposed will come down with AIDS, and another 25 percent may become ill with lesser symptoms.

A repeatedly positive test does not predict who will get the disease, but AIDS experts say that those who test positive may be infectious to others, even though they themselves have no symptoms.

Dr. Thomas Vernon, executive director of the Colorado Department of Health, said in an interview that his department's plan is "an opportunity to apply to AIDS infection what we have been applying to syphilis infection for decades . . . . We have tremendous confidence in our system of confidentiality."

Vernon said that after a public hearing on Wednesday, the Colorado Board of Health, a 9-member policy-making and regulatory body appointed by the governor, voted unanimously to require laboratories to report confirmed positive AIDS antibody blood tests on a confidential form. It includes the patient's name and address, the doctor's name and other medical information, he said.

"We will review that result with the doctor," said Vernon, to make sure that the individual gets adequate follow-up and counseling about the risks of transmitting the disease to others, and if necessary contact the individual.

"We have a disease which is terrifying the country, we have no vaccine and no definitive treatment. What we do have that would at least begin to control the transmission is counseling and education of the individual who may be infectious. I think of counseling as being our vaccine for the disease for the short-term," Vernon said.

Because of state regulations, the health board must again vote on the measure at its next meeting, on Sept. l8, and if approved as expected, it would take effect Oct. 30, he said.

At Wednesday's hearing in Denver, the state health plan met with opposition from representatives from the American Civil Liberties Union of Colorado, the Colorado AIDS Project, a Denver health official and a local blood bank official, according to those who attended the meeting. A compromise proposal to delay implementation until early l987 was rejected, they said.

Carol Lease, chairwoman of the Colorado ACLU, said yesterday that she believed that state health fficials were well-meaning, "but I don't think they are aware of the potential abuse. I don't think they are aware of the adverse impact this would have in the gay community," discouraging people from getting the blood test.