Oseltamivir Use Among Children and Adults Hospitalized With Community-Acquired Pneumonia

Pure Viral Sepsis Secondary to Community-Acquired Pneumonia in Adults: Risk and Prognostic Factors

We investigated the risk and prognostic factors of pure viral sepsis in adult patients with community-acquired pneumonia (CAP), using the Sepsis-3 definition. Pure viral sepsis was found in 3% of all patients (138 of 4028) admitted to the emergency department with a diagnosis of CAP, 19% of those with CAP (138 of 722) admitted to the intensive care unit, and 61% of those (138 of 225) with a diagnosis of viral CAP. Our data indicate that males and patients aged ≥65 years are at increased risk of viral sepsis.

Influenza

Influenza is an infectious respiratory disease that, in humans, is caused by influenza A and influenza B viruses. Typically characterized by annual seasonal epidemics, sporadic pandemic outbreaks involve influenza A virus strains of zoonotic origin. The WHO estimates that annual epidemics of influenza result in ~1 billion infections, 3–5 million cases of severe illness and 300,000–500,000 deaths. The severity of pandemic influenza depends on multiple factors, including the virulence of the pandemic virus strain and the level of pre-existing immunity. The most severe influenza pandemic, in 1918, resulted in >40 million deaths worldwide. Influenza vaccines are formulated every year to match the circulating strains, as they evolve antigenically owing to antigenic drift. Nevertheless, vaccine efficacy is not optimal and is dramatically low in the case of an antigenic mismatch between the vaccine and the circulating virus strain. Antiviral agents that target the influenza virus enzyme neuraminidase have been developed for prophylaxis and therapy. However, the use of these antivirals is still limited. Emerging approaches to combat influenza include the development of universal influenza virus vaccines that provide protection against antigenically distant influenza viruses, but these vaccines need to be tested in clinical trials to ascertain their effectiveness.