recommended for people 65 years and older; various influenza (flu) vaccinations are authorized for use in people of various age groups. On March 3, 2022, the FDA's Vaccines and Related Biological Products Advisory Committee (VRBPAC) convened in Silver Spring, Maryland, to choose the influenza viruses that will make up the influenza vaccine for the 2022–2023 influenza season in the United States. The committee proposed using A(H1N1)pdm09, A(H3N2), and B/Austria/1359417/2021-like viruses for trivalent influenza vaccines to be utilized in the U.S. for the 2022–2023 influenza season. Influenza B throughout the decades: Its discovery and development In 1940, an acute respiratory illness outbreak in Northern America led to the discovery of influenza B virus (IBV), which was later discovered to not have any antigenic cross-reactivity with influenza A virus (IAV). Based on calculations of the rate of amino acid substitutions in HA proteins, it was estimated that IBV and IAV diverged from one another around 4000 years ago. However, the mechanisms of replication and transcription, as well as the functionality of the majority of viral proteins, appear to be largely conserved, with some unusual differences. Although IBV has occasionally been found in seals and pigs, its primary host species is the human. IBVs can also spread epidemics throughout the world, but they receive less attention than IAVs do due to their less prevalent nature, both in infecting hosts and in the symptoms that result from infection. IBVs used to be unclassified, but since the 1980s, they have been divided into the B/Yamagata and B/Victoria lineages. IBVs have further divisions known as clades and sub-clades, just like IAVs do. Hemagglutinin (HA) and neuraminidase (NA) are two virus surface antigens that are constantly changing. Antigenic drift or antigenic shift are two possible influenza viral changes. Small changes in the HA and NA of influenza viruses caused by antigenic drift result in the creation of novel strains that the immune system of humans might not be able to identify. These emerging strains are the influenza virus's evolutionary responses to a potent immunological response across the population. The main cause of influenza recurrence is antigenic drift, which makes it essential to reevaluate and update the influenza vaccine's ingredient list every year. Annual influenza outbreaks are caused by antigenic drift and declining immunity, when the residual defenses from prior exposures to related viruses are incomplete. Antigenic drift occurs in Influenza A, B, and C. Hemagglutination-inhibition experiments using