This clinical trial evaluates the immune response to Bexsero, a vaccine against invasive meningococcal disease caused by group B bacteria. The study focuses on individuals aged 10 to 20 years who previously received this vaccine in early childhood. Meningococcal disease is a serious infection that can cause inflammation of the membranes surrounding the brain and spinal cord.
The vaccine is given as a suspension for intramuscular injection using a pre-filled syringe. Each participant will receive one dose of 0.5 milliliters of the vaccine. The study compares the immune response between people who received the vaccine in early childhood and those who have never received it before.
The main purpose is to determine if people previously vaccinated with Bexsero show a stronger immune response to a booster dose compared to those receiving the vaccine for the first time. The study will monitor participants for 31 days after vaccination to assess both the immune response and safety of the vaccine.



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