Insights into host responses, viral evolution, and implications for vaccines and therapeutics for Mpox.

PURPOSE OF REVIEW: Understanding the immunology and pathogenesis of Mpox, an illness caused by the re-emerging monkeypox virus (MPXV), which has recently been responsible for human outbreaks globally. In particular, summarizing the knowledge on host immune responses to Mpox, the mechanisms underlying viral pathogenesis, viral evolution, and recent human outbreak data on vaccines and emerging immunotherapeutics.

RECENT FINDINGS: Recurrent global outbreaks of Mpox led the WHO to declare it a public health emergency of international concern twice, in May 2022 and August 2024, with the emergence of a new clade Ib. Although vaccines are available for Mpox access is challenging in certain communities and sustained transmission may promote emergence of novel virus variants. Mpox is more severe and can be lethal in immunocompromised people, notably those with human immunodeficiency virus (HIV), children, and pregnant persons.

SUMMARY: Insights into the immunology and pathogenesis including data from contemporary outbreaks, highlight emerging priorities for research and preparedness for fighting the disease. This also emphasizes the importance of understanding the unique features of Mpox in HIV co-infected individuals who have disproportionate burden of severe infections and the need vaccine and therapeutic optimization especially for immunocompromised patients.