This clinical trial is focused on studying the immune responses to influenza vaccinations and viruses among healthcare personnel. Influenza, commonly known as the flu, is a contagious respiratory illness caused by influenza viruses. The study will use a vaccine that contains inactivated, split virus or surface antigen components, which include strains like A/Texas/50/2012 (H3N2) and A/California/7/2009 (H1N1). These components are designed to help the body build immunity against the flu.
The purpose of the study is to assess the presence and level of antibodies, which are proteins in the blood that fight infections, against the circulating influenza virus strains and the vaccine strains of the current season. Participants will receive the vaccine through an injection into the muscle. Blood samples will be taken before and after vaccination to measure the immune response. The study will also look at cellular immunity, which involves the body’s cells responding to the virus, and will measure substances like cytokines, which are proteins that help control the immune response.
The study will take place over several years, with the goal of understanding how well the vaccine works in healthcare workers who are regularly exposed to the flu. This information could help improve future flu vaccines and protect people from getting sick. Participants will be monitored throughout the study to ensure their safety and to gather important data on how their bodies respond to the vaccine.



Finland