What is today the Division of Infectious Diseases and Immunology was established as the Division of Immunology and Infectious Diseases in the 1940s by NYU School of Medicine faculty involved in the clinical investigation of the effects and efficacy of antibiotics.

From 1959 to 2000 the division was led by Dr. H. Sherwood Lawrence, who oversaw many significant achievements. Infectious diseases consultations were begun at Bellevue Hospital in 1969. A clinical fellowship in infectious diseases was launched in 1975.

Ten years later Bellevue Hospital established a dedicated inpatient service with 40 beds for people with AIDS, staffed by physicians in the Division of Infectious Diseases. Today that number of beds has been reduced to 30, thanks to the efficacy of anti-retroviral therapy.

The Division of Infectious Diseases and the Infectious Diseases Fellowship Training Program were based solely at Bellevue Hospital until 1993, when the Fellowship Training Program at the VA Medical Center New York merged with the Bellevue program.

In 2002 the Fellowship Training Program was expanded to include Tisch Hospital. Dr. Robert S. Holzman served as Acting Director of the division from 2000 to January 2003, when Dr. Joel D. Ernst became the new Director of the division after a national search.