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.

Overview of reemerging mpox infection with a focus on neurological manifestations

“…The mortality rate varies across virus clades, with one death per 100 infected people in the West African clade and one death per 10 infected people in the Central African clade. 12,26 The potential rapid spread of mpox infections observed in May 2022 remains uncertain, yet the virus, though not highly contagious, can lead to severe complications, particularly in immunodeficient individuals or those undergoing chemotherapy, resulting in increased hospitalisation rates (Figure 1). 28,29 Complications include chest infections, neurological issues such as encephalitis, sepsis, and eye infections, potentially leading to blindness.…”

“…Transmission primarily occurs through monkeys and terrestrial rodents such as mice and squirrels, although human‐to‐human spread is also feasible. The mortality rate varies across virus clades, with one death per 100 infected people in the West African clade and one death per 10 infected people in the Central African clade 12,26 …”

Mpox (formerly monkeypox): pathogenesis, prevention and treatment

“… 42 , 43 It then spreads throughout the body via tissue-resident immune cells and draining lymph nodes. 42 , 44 This constitutes the latent period for Mpox virus infection, which typically lasts up to two weeks. Throughout this period, individuals infected with Mpox are generally asymptomatic and devoid of lesions.…”

A Review of the Past, Present, and Future of the Monkeypox Virus: Challenges, Opportunities, and Lessons from COVID-19 for Global Health Security

“…It is important to note here that global commitment, along with the distinctive properties of these vaccines, such as advances in technological innovations to produce heat-stable, freeze-dried vaccines capable of surviving at tropical temperatures without refrigeration, along with the production of easy-to-use and cost-effective bifurcated needles to administer doses, contributed to successful vaccination campaigns in high-risk countries, which were part of the core basis of smallpox's eradication [64]. Despite their efficacy, the first-generation vaccines were associated with rare but severe adverse events [61][62][63][65][66][67][68]. These vaccines consisted of live, replication-competent VACV [63,65], which likely contributed to the occurrence of adverse effects due to VACV's replication and spread within the vaccinees.…”