A contemporary review of clade-specific virological differences in monkeypox viruses

Abstract

Background: Monkeypox virus (MPXV) is an emerging zoonotic virus that has had on-going public health impacts in endemic regions of Central and West Africa for over a half-century. Historically, the MPXV clade endemic in regions of Central Africa is associated with higher morbidity and mortality as compared with the clade endemic in West Africa.

Objectives: Here, we review the virological characteristics of MPXV and discuss potential relationships between virulence factors and clade- (and subclade-) specific differences in virulence and transmission patterns.

Sources: Targeted search was conducted in PubMed using ((monkeypox virus) OR (Orthopoxvirus)) AND (zoonosis)) OR ((monkeypox) OR (human mpox).

Content: Forty-seven references were considered that included three publicly available data reports and/or press releases, one book chapter, and 44 published manuscripts.

Implications: Although zoonosis has been historically linked to emergence events in humans, epidemiological analyses of more recent outbreaks have identified increasing frequencies of human-to-human transmission. Furthermore, viral transmission during the 2022 global human mpox outbreak, caused by a recently identified MPXV subclade, has relied exclusively on human-to-human contact with no known zoonotic link.

Keywords: Clades; Monkeypox virus; Mpox; Pathogenesis; Virology; Virulence.