Influenza

Influenza, commonly known as the flu, is an acute respiratory infection caused by influenza viruses, primarily types A and B, which are responsible for seasonal epidemics worldwide. Influenza viruses belong to the Orthomyxoviridae family and have a negative-sense, single-stranded RNA genome (Gaitonde DY et al. (2019)). The virus spreads easily through respiratory droplets when infected individuals cough or sneeze. Typical symptoms include a sudden onset of fever, cough, sore throat, body aches, and fatigue. Symptoms usually begin 1–4 days after infection and last about a week. Most people recover without medical interventions, but severe cases, particularly in individuals with risk factors, may require antiviral treatment and hospitalization.

The pathogenesis of influenza involves the virus infecting respiratory epithelial cells (Wu NH et al. (2016)). The virus binds to sialic acid receptors on the host cells, leading to entry, replication, and the release of new virus particles. This infection triggers an immune response, where cytokines and chemokines attract inflammatory cells, such as neutrophils and macrophages, to the site. Severe infections can cause complications like acute respiratory distress syndrome (ARDS) and secondary bacterial infections, with both direct viral damage and an overactive immune response contributing to severe outcomes.

Differential Abundance Analysis Results

This section presents the results of the differential protein abundance analysis, visualized through a volcano plot and summarized in the accompanying table for all three comparisons: 1) disease vs. healthy samples, 2) disease vs. diseases from the same class, and 3) disease vs. all other diseases.