Virological surveillance of influenza B virus during the 2023/24 season

Influenza B virus is one of the primary pathogens responsible for seasonal flu epidemics, leading to significant morbidity and mortality worldwide. It causes respiratory illnesses characterized by symptoms such as fever, cough, sore throat, body aches, and fatigue. Unlike Influenza A, Influenza B primarily affects humans and has a lower mutation rate, yet it still undergoes antigenic mutations, resulting in frequent changes to its surface proteins, particularly hemagglutinin (HA). This continuous evolution necessitates ongoing surveillance to monitor circulating strains and ensure the effectiveness of vaccines. Preventive measures against Influenza B include annual vaccination and rigorous surveillance, which involves the collection and analysis of viral samples to identify prevalent strains, monitor their evolution, and assess the antigenic match between circulating viruses and vaccine formulations. During my internship at the Microbiology and Virology Unit of the University of Padua Hospital, I focused on analyzing the hemagglutinin regions of Influenza B virus samples. This data is crucial for monitoring viral evolution and informing the annual update of vaccine compositions. My findings contribute to the global efforts in characterizing circulating viruses and ensuring that vaccines remain effective, thereby aiding in the reduction of influenza-related disease burden.