Written as an editorial commentary regarding Kaselitz et al. Impact of Vaccination on Morbidity and Mortality in Adults Hospitalized With Influenza A, 2014–2015 pages 328–333 of the Journal.
Annual influenza vaccination is an important public health measure for preventing influenza infection. The US Advisory Committee on Immunization Practices recommends annual influenza vaccination for all individuals 6 months or older. High-risk individuals, their close contacts, and health care workers should remain high-priority recipients in vaccination campaigns. The goal of the influenza vaccine is to prevent illness, but as we know, the efficacy is not 100% and for most seasons is approximately 30% to 60% at preventing documented influenza disease. But the value of the vaccine also extends to reducing morbidity and mortality in patients who develop clinical illness due to influenza.
In this issue, Kaselitz et al1 report the results of a retrospective study of adult patients hospitalized with acute influenza A at a large tertiary medical center during the respiratory season of 2014–2015; they observed patients who had been vaccinated for influenza at least 2 weeks prior to hospitalization had a lower rate of serious outcomes compared to unvaccinated patients.1 After adjusting for age, race, sex, presence of chronic lung and cardiovascular disease, and smoking status, vaccination was associated with a decreased odds of death. Of note, this was observed despite the poor vaccine matching recognized during that season. This is an important message and represents an additional reason for immunization. The authors cite several other studies showing reduction in mortality in hospitalized patients. An addition study not cited in their study was published last year from Taiwan.2 In a matched cohort study of patients older than 66 years, those who received influenza vaccine and later underwent surgery had a lower in-hospital mortality than unvaccinated patients.
So, the study by Kaselitz et al,1 as well as the others cited in their report, should provide added evidence regarding the benefit of influenza vaccine. I am often approached by friends and patients who state that despite having received the vaccine they still developed “the flu.” My response is something like “But you did not die.”
1. Kaselitz T, Martin ET, Power L, et al. Impact of vaccination on morbidity and mortality in adults hospitalized with influenza
A, 2014–2015. Infect Dis Clin Pract
2. Liu WC, Lin CS, Yeh CC, et al. Effect of influenza
vaccination against postoperative pneumonia and mortality for geriatric patients receiving major surgery: a nationwide matched study. J Infect Dis