Epstein-Barr Virus (EBV) gH/gL/gp42-Ferritin Nanoparticle Vaccine With or Without gp350-Ferritin in Healthy Adults With or Without EBV Infection

Background: Epstein-Barr virus (EBV) is the primary cause of infectious mononucleosis, commonly known as mono. EBV infects more than 90% of the world s population. Mono can be serious, and it can lead to severe illnesses like cancer and autoimmune diseases. Researchers want to test vaccines that may help prevent EBV and associated diseases. Objective: To test two EBV vaccines: EBV gH/gL/gp42-ferritin and EBV gp350-ferritin. Eligibility: Healthy EBV-negative or EBV-positive people aged 18 to 29. Design: Participants will be screened. They will have a physical examination. They will give blood and saliva samples. They will receive 3 doses of the study vaccine as an injection in the shoulder muscle. They will get either one vaccine or a combination of both vaccines. Participants will get their first dose of the vaccine at visit 1, the second dose about 30 days later, and the final dose about 90 days after that. Participants will be given a memory aid so they can record any symptoms and side effects between visits. This can be done either on paper or online through a link that is emailed to them. There are 6 required in-person visits. There are also 2 optional visits. In between the in-person visits are 7 telehealth visits or phone calls. Each visit may take up to 4 hours. The study will last for about 17 months. Participants will have the option of staying in the study for an additional year.