March 1988

Association of Influenza Immunization With Reduction in Mortality in an Elderly PopulationA Prospective Study

Author Affiliations

From Hackensack (NJ) Medical Center and New Jersey Medical School, Newark (Dr Gross); Division of Virology, Office of Biologics Research and Review, National Center for Drugs and Biologics, Food and Drug Administration, Bethesda, Md (Dr Quinnan); Jewish Home and Hospital for the Aged, New York (Drs Rodstein and Neufeld); Microbiology and Infectious Diseases Program, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Md (Drs LaMontagne, Kaslow, and Saah); Department of Geriatrics, Mount Sinai School of Medicine, New York (Drs Rodstein and Neufeld); School of Public Health (Biostatistics), College of Physicians and Surgeons, Columbia University, New York (Dr Wallenstein); and St Vincent's Hospital Cystic Fibrosis Clinic, New York Medical College (Drs Denning and Gaerlan).

Arch Intern Med. 1988;148(3):562-565. doi:10.1001/archinte.1988.00380030068015

• We prospectively studied the efficacy of influenza vaccine during an influenza A/Arizona/80 (H3N2) outbreak at the Jewish Home and Hospital for the Aged in New York in the winter season of 1982 to 1983. All patients had been offered influenza vaccine before the outbreak; 181 chose to be vaccinated and 124 refused vaccination but agreed to participate in the study. Among those with serologic evidence of influenza infection, respiratory illness was significantly more common in the unvaccinated group (six of 14 vs one of 22). The overall mortality was 13 (7.2%) of 181 in the vaccinated group and 22 (17.7%) of 124 in the control group. The vaccinated and the control groups were examined for comparability. A logistic regression analysis, which controlled for differences in sex and level of nursing care, indicated that the difference in mortality was still significant, with a summary odds ratio of 2.7. The relative risk of death in the unvaccinated group was comparable at 2.18. Influenza vaccine reduced the mortality by 59% in the vaccinated group compared with the control group.

(Arch Intern Med 1988;148:562-565)