June 5, 1981

Pneumocystis Pneumonia — Los Angeles

CDC publishes the first report of the illness later named AIDS

Two of the five men were already dead when the two-page bulletin appeared on 5 June 1981. None of them knew each other.

Five patients, three hospitals

The Centers for Disease Control — its 1981 name; “and Prevention” was added in 1992 — published “Pneumocystis Pneumonia—Los Angeles” in its Morbidity and Mortality Weekly Report.

It described five young gay men, aged 29 to 36, treated at three Los Angeles hospitals between October 1980 and May 1981 for biopsy-confirmed Pneumocystis carinii pneumonia. Two had died by publication.

Why it was strange

That pneumonia occurred almost exclusively in severely immunosuppressed patients. These men had no apparent shared underlying immune disorder — and the report noted they did not know one another and had no known common contacts.

CDC's accompanying note proposed an unexplained cellular-immune dysfunction linked to a common exposure. It named no cause, did not identify HIV and did not use the word AIDS, a name adopted in 1982.

What the bulletin set off

Requests to CDC for pentamidine — unlicensed and obtainable only from the agency — had already flagged unusual PCP cases to federal scientists. The Los Angeles clinicians, led by Michael Gottlieb, and the CDC field officer Wayne Shandera had submitted the cluster in early May.

After publication, physicians in New York, San Francisco and elsewhere reported additional unusual cases. CDC assembled an investigative team in June and formed its Kaposi's Sarcoma and Opportunistic Infections task force that summer.

Sources

Researched 23 Aug 2026 7 sources 2 audit passes

How this was checked

Researched from the web into a fact sheet, rewritten from that sheet, then audited against it by a different model. How the pipeline works →

What the sources leave uncertain

A later CDC HTML reprint says “June 4,” but the original MMWR issue citation, CDC’s anniversary account and CDC’s institutional history consistently identify June 5, 1981. The June 4 wording appears to be a reprint error.