Influvax Tetra 0.5 mL is a quadrivalent influenza vaccine designed to provide immunization against four strains of the influenza virus, including two A strains and two B strains. This vaccine is formulated to help protect individuals from seasonal flu by stimulating the immune system to produce antibodies against the virus without causing the disease. Administered as an intramuscular injection, Influvax Tetra is typically recommended for individuals aged six months and older, especially those at higher risk of complications from influenza, such as the elderly, young children, and individuals with certain chronic health conditions. Common side effects may include soreness at the injection site, mild fever, and fatigue. Vaccination is an essential public health measure to reduce the incidence of influenza and its associated complications during flu season.