Genomic Evolution and Epidemiological Impact of Ongoing Clade Ib MPox Disease: A Narrative Review

Abstract

Clade 1b of the MPox virus has emerged as a highly virulent strain, causing significant public health challenges globally. Initially endemic to Central Africa, this strain has spread to nonendemic regions, including Europe, Asia, and the Americas. With its high transmission rate and severe outcomes, especially among vulnerable populations like children, Clade 1b has raised global concerns. The Africa Center for Disease Control and Prevention (CDC) has declared it a public health emergency of international concern. Clade 1b MPox shows a higher case fatality rate and increased transmissibility compared to other strains. It has moved beyond traditional zoonotic transmission to widespread human-to-human transmission. The variant's spread to countries such as Sweden and Thailand demonstrates its global reach. Public health efforts, including cross-border coordination, rapid response teams, and awareness campaigns, have been essential in containing the outbreaks. However, barriers such as limited resources, vaccine shortages, and logistical challenges in conflict-affected areas have hindered effective control, particularly in low-resource regions. The spread and severity of Clade 1b MPox highlight the need for global cooperation to strengthen surveillance, improve diagnostic capabilities, and expand healthcare infrastructure in affected areas. Enhancing access to vaccines and treatments, along with educating the public on preventive measures, will be key to controlling transmission. Ongoing research and monitoring are essential to mitigate future outbreaks and minimize the virus's global impact.

Keywords: clade 1b MPox; global outbreak; public health emergency; surveillance; vaccine access; virus transmission.

Figure 1

Illustrates the progression of MPox infection from entry into the body, replication in lymph nodes, and systemic blood spread, leading to severe symptoms and immune evasion mechanisms.

Figure 2

A visual representation of the genetic relationship between Clade I (Central African Clade) and Clade II (West African Clade), highlighting key mutations and transmission patterns.

Figure 3

Global spread and transmission patterns of Clade 1B: This map illustrates the geographic distribution and severity of Clade 1B infections.