Evolución del paciente hospitalizado con gripe durante 2016–2020 según su estado vacunal

Introduction

Influenza vaccination is an effective measure to reduce hospital admissions and mortality. The objective of this study is to quantify the effectiveness of influenza vaccination in patients hospitalized for influenza to prevent its evolution to severity, considering other known factors that influence such severity.

Methods

Cross-sectional study of the 2016–2017 to 2019–2020 influenza epidemiological seasons with patients hospitalized at the Nuestra Señora de la Candelaria University Hospital in Tenerife diagnosed with influenza. Basic demographic and evolution variables were studied. The criteria for clinical severity used is that established by the Spanish National Epidemiology Center. Using multivariable binary logistic regression, the risk of progression to severity associated with influenza vaccination status was estimated.

Results

A total of 1,416 patients were collected. Of whom 50% were women, 56% older than 64 years, 17% with flu vaccination, 24% evolved to severity, 3% died, 72% treated with oseltamivir, 23% (CI95%: 19–27) not treated with oseltamivir were admitted to the ICU, compared to 1.5% (CI95%: 1–2) treated, 25% (CI95%: 23–28) of the non-vaccinated patients developed severity, compared to 18% (CI95%: 13–23) of the vaccinated. The odds ratio (OR) to severe evolution was 1.6 (CI95%: 1.1–2.2) for those not vaccinated.

Conclusions

Patients hospitalized for influenza who have not received influenza vaccination have a more than double the risk of a serious evolution of influenza compared to correctly vaccinated patients. The combination of oseltamivir and vaccination reduces their admission to the ICU by almost a fifth.