Influenza vaccination of healthcare workers in acute-care hospitals: a case-control study of its effect on hospital-acquired influenza among patients

Abstract

BackgroundIn acute-care hospitals, no evidence of a protective effect of healthcare worker (HCW) vaccination on hospital-acquired influenza (HAI) in patients has been documented. Our study objective was to ascertain the effectiveness of influenza vaccination of HCW on HAI among patients.MethodsA nested case-control investigation was implemented in a prospective surveillance study of influenza-like illness (ILI) in a tertiary acute-care university hospital. Cases were patients with virologically-confirmed influenza occurring ≥ 72 h after admission, and controls were patients with ILI presenting during hospitalisation with negative influenza results after nasal swab testing. Four controls per case, matched per influenza season (2004-05, 2005-06 and 2006-07), were randomly selected. Univariate and multivariate conditional logistic regression models were fitted to assess factors associated with HAI among patients.ResultsIn total, among 55 patients analysed, 11 (20%) had laboratory-confirmed HAI. The median HCW vaccination rate in the units was 36%. The median proportion of vaccinated HCW in these units was 11.5% for cases vs. 36.1% for the controls (P = 0.11); 2 (20%) cases and 21 (48%) controls were vaccinated against influenza in the current season (P = 0.16). The proportion of ≥ 35% vaccinated HCW in short-stay units appeared to protect against HAI among patients (odds ratio = 0.07; 95% confidence interval 0.005-0.98), independently of patient age, influenza season and potential influenza source in the units.ConclusionsOur observational study indicates a shielding effect of more than 35% of vaccinated HCW on HAI among patients in acute-care units. Investigations, such as controlled clinical trials, are needed to validate the benefits of HCW vaccination on HAI incidence in patients.

Evaluating influenza vaccination campaigns beyond coverage: A before-after study among health care workers

“…Influenza simultaneously converts HCW into a human resource to be protected, ie, by not losing them to sick leave, 2,3 and into potential transmitters of influenza to patients who are vulnerable to the possible complications of the disease. 4,5 Adverse effects of the influenza vaccine are rare and mild, and the vaccine is moderately, but significantly, effective. 6 Nevertheless, there are various barriers to vaccination in HCW, including the fear of adverse effects, doubts about vaccine effectiveness, revaccination year after year, and underestimation of the severity of influenza.…”

Trust and the demand for autonomy may explain the low rates of immunizations among nurses

“…1,2 Vaccination of HCW has been shown to benefit their patients. 3 Therefore, health authorities in the developed countries formulated recommendations for vaccination of HCW. [4][5][6][7] Pertussis vaccines have been in routine pediatric use for more than 50 y and a drastic decrease in the incidence of the disease has been achieved.…”

Assessment of the belief and attitudes of Iranian healthcare personnel’s toward the influenza infection and influenza vaccination

“…The best method for prevention of influenza is vaccination, which results in decreasing of death in the HCPs and vulnerable patients [4, 19]. The current study found that the influenza vaccination rate among the HCPs was 57.7%.…”