First licensed HIV antibody test

In January 1983 CDC called a public meeting on protecting the nation's blood supply from AIDS. Representatives of the FDA, the National Institutes of Health, blood services, the hemophilia community and gay activists attended, and they could not agree on what to do. In March the Public Health Service asked members of groups at increased risk to refrain from donating blood or plasma. By January 1985, blood and blood products accounted for about 2 percent of reported AIDS cases.

Margaret Heckler, the health and human services secretary, announced in 1984 that Robert Gallo and colleagues at the National Cancer Institute had found the cause of AIDS, a retrovirus they called HTLV-III, and that a diagnostic blood test was being developed. The virus also went by other names, among them lymphadenopathy-associated virus (LAV). The first antibody tests were modified enzyme-linked immunosorbent assays, or ELISAs, built on antigens from whole disrupted virus.

The Public Health Service issued provisional recommendations for screening donated blood and plasma on 11 January 1985. In research studies the ELISA had found antibody in 68 to 100 percent of patients with AIDS, 56 to 72 percent of people with hemophilia A, 22 to 65 percent of homosexual men and 87 percent of drug injectors admitted to one New York City detoxification program, but in fewer than 1 percent of people with no known risk. Donors were to be told that their blood would be tested and that they would be notified if it was positive. Positive specimens were to be retested first, and the Western blot, read as positive if bands for the p24 or gp41 proteins appeared, was the best-studied follow-up test.

The FDA licensed the first commercial test on 2 March 1985, and blood banks began screening the US supply. The recommendations had warned of false positives in early use and noted that some infected people had gone more than six months without detectable antibody. A more specific Western blot test kit was approved on 29 April 1987.