When Dingle was appointed to lead the US Army's Commission on Acute Respiratory Diseases during World War II, he recruited Alexander Langmuir to serve at Fort Liberty in North Carolina from 1942 to 1946.

[1] In 1946, Langmuir began working as an Associate Professor of Epidemiology at the Johns Hopkins School of Hygiene and Public Health, but he quickly grew disillusioned with academia.

However, the February 1946 New York City tugboat strike led Stebbins to controversially close all businesses and schools to reserve fuel for public utilities, hospitals, and emergency responders.

Frustrated with backlash to the 18-hour shutdown, O'Dwyer ignored all eight recommendations proposed on March 1, 1946, including Langmuir, and appointed New York City Hospital Commissioner Edward M. Bernecker.

Additionally, Langmuir's efforts to include environmental health under the CDC's purview led to the 1983 creation of the Agency for Toxic Substances and Disease Registry.

[12] In this role, Langmuir instituted a system of 108 US cities reporting their deaths by cause to the CDC on a weekly basis, which is still utilized for tracking influenza-like illness.

[21] In 1976, virologist Ho Wang Lee identified that the Korean hemorrhagic fever reported by American soldiers was actually due to endemic Hantaan orthohantavirus.

[23] In January 1976, soldiers at Fort Dix, New Jersey, contracted swine influenza A/H1N1, prompting comparisons to the 1918–1920 flu pandemic that originated from Camp Funston, Kansas.

As the US Department of Justice evaluated over 4,000 claims of injury, Langmuir led the EIS in studying the mechanisms by which vaccination can trigger this autoimmune condition to establish clinical case criteria and identify genuine instances of Guillain–Barré syndrome.

[25] Tasked with identifying the outbreak's source by Surgeon General Leonard A. Scheele, Langmuir ordered each state to designate a public health officer that would report all cases of polio to conduct a case-control study, ultimately finding that two lots of Cutter Laboratories' vaccine had been contaminated with live poliovirus.

During the 1970s, EIS officers identified that the Dalkon Shield's tail string allowed bacteria to pass from the cervix to the uterus, resulting in an elevated risk for pelvic inflammatory disease and septic abortion.

Instead, Langmuir proposed that Athens experienced an influenza outbreak from zoonotic spillover of a livestock strain, leading to skin lesions and damaged respiratory mucosa colonized by Staphylococcus.

Langmuir argued that the Athenian hoplites experienced a roughly 33% mortality rate, while the Spartans did not contract influenza during the Archidamian War, because overcrowding within the Long Walls of Athens increased the transmissibility of disease.

[7] The October 1996 supplement to volume 144, issue 8 of the American Journal of Epidemiology was dedicated to covering Langmuir's impact on public health with many of the articles written by EIS alumni.

[35] Since 1966, the Epidemic Intelligence Service has awarded the Alexander D. Langmuir Prize at its annual conference to the manuscripts of current EIS officers and first-year alumni.

[5] Since 1972, the Epidemic Intelligence Service's annual conference has included a Alexander D. Langmuir Lecture, the first of which was delivered by Charles H. Rammelkamp Jr. on the prevention of rheumatic heart disease.

[40] In 1987, the Charles A. Dana Foundation conferred a Pioneer Achievement Award on Langmuir for establishing the United States' public health surveillance during his time as Chief Epidemiologist of the CDC.