An mpox quadrivalent mRNA vaccine elicits sustained and protective immunity in mice against lethal vaccinia virus challenge.

Assessing the long-term efficacy of MPXV vaccine candidates is crucial for the global response to the ongoing mpox epidemic. Built upon our previous study of the mpox quadrivalent mRNA vaccine, herein we reported that MPXV-1103 could elicit sustained humoral and cellular immunity in mice, including the induction of MPXV A35/B6/A29/M1-specific IgG antibodies, VACV neutralizing antibodies and activated cytotoxic CD8T cells, which provides 100% protection against lethal VACV challenge even at 280 days after the first vaccination. Our results provide critical insights for orthopoxvirus vaccine development.

Duration of humoral immunity from smallpox vaccination and its cross-reaction with Mpox virus.

The ongoing pandemic caused by mpox virus (MPXV) has become an international public health emergency that poses a significant threat to global health. The vaccinia virus Tiantan strain (VTT) was used to vaccinate against smallpox in China 42 years ago. It is urgent to assess the level of immunity to smallpox in individuals vaccinated 43 or more years ago and evaluate their immunological susceptibility to MPXV.

Monkeypox virus: a re-emergent threat to humans.

Human monkeypox (MPX) is a rare zoonotic infection characterized by smallpox-like signs and symptoms. It is caused by monkeypox virus (MPXV), a double stranded DNA virus belonging to the genus Orthopoxvirus. MPX was first identified in 1970 and mostly prevailed in the rural rainforests of Central and West Africa in the past.