With the expansion of mpox virus infection from endemic to a global epidemic in 2022, the WHO declared that the mpox event constituted a Public Health Emergency of International Concern. Due to the high degree of gene sequence similarity among orthopox viruses and cross-reactive antibodies induced by orthoviruses, smallpox vaccination may affect the immune response induced by mpox virus infection. The analysis of the protective effects of smallpox vaccination against mpox virus infection will help define the focus of prevention and control. In this review, we clarify the protection of the smallpox vaccine against mpox virus infection by analyzing the correlation between smallpox vaccination, immune response status, and clinical data and providing evidence for the prevention, control, and strategies of mpox epidemics.
Humans ; Smallpox/epidemiology* ; Monkeypox/drug therapy* ; Smallpox Vaccine/therapeutic use* ; Vaccination ; Immunity