Human Monkeypox: A Comprehensive Overview of Epidemiology, Pathogenesis, Diagnosis, Treatment, and Prevention Strategies

Abstract

Monkeypox virus (MPXV) is an emerging zoonotic virus that belongs to the Orthopoxvirus genus and presents clinical symptoms similar to those of smallpox, such as fever and vesicular-pustular skin lesions. However, the differential diagnosis between smallpox and monkeypox is that smallpox does not cause lymphadenopathy but monkeypox generates swelling in the lymph nodes. Since the eradication of smallpox, MPXV has been identified as the most common Orthopoxvirus to cause human disease. Despite MPXV being endemic to certain regions of Africa, the current MPXV outbreak, which began in early 2022, has spread to numerous countries worldwide, raising global concern. As of the end of May 2023, over 87,545 cases and 141 deaths have been reported, with most cases identified in non-endemic countries, primarily due to human-to-human transmission. To better understand this emerging threat, this review presents an overview of key aspects of MPXV infection, including its animal reservoirs, modes of transmission, animal models, epidemiology, clinical and immunological features, diagnosis, treatments, vaccines, and prevention strategies. The material presented here provides a comprehensive understanding of MPXV as a disease, while emphasizing the significance and unique characteristics of the 2022 outbreak. This offers valuable information that can inform future research and aid in the development of effective interventions.

Keywords: Orthopoxvirus; monkeypox (MPX); public health emergency; smallpox; zoonotic disease.

Figure 1

Confirmed mpox cases and deaths in the world (A,B). Global cases and deaths, respectively (data represent the cases per week) (C). Top 10 countries with confirmed cases and (D) top 10 countries with reported deaths. Data are derived from the WHO (accessed on 29 May 2023).

Figure 2

Lifecycle of MPXV. Schematic overview of the processes involved in the attachment, replication, and creation of viral offspring in MPXV is provided, along with the mechanisms of action of therapeutic agents that have been suggested for the treatment of mpox infection. Figure created with BioRender.com (accessed on 3 May 2023).