New research to be presented at this year's European Congress of Clinical Microbiology and Infectious Diseases (ECCMID 2024) in Barcelona, Spain (27-30 April) shows that the antibodies produced by Modified Vaccinia virus Ankara - Bavarian Nordic (MVA-BN) vaccination against mpox wane significantly within a year of receiving the vaccination – but in people with pre-existing immunity due to childhood smallpox vaccination in childhood, antibody levels remain high in almost all cases.