Mpox: A Re-emerging Zoonotic Disease Threatening Global and African Health

By: Nesredin Hassen Yesuf

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Introduction

In recent years, Mpox—formerly known as monkeypox—has evolved from a largely neglected tropical disease to a global public health concern. The viral illness, long endemic to parts of Central and West Africa, drew global attention in 2022 when it began spreading rapidly across countries with no prior history of outbreaks. Despite this, Mpox remains most threatening in the very regions where it originated, especially Sub-Saharan Africa, including Ethiopia. Understanding this disease requires not only biomedical insight but also a critical reflection on global health preparedness, surveillance equity, and zoonotic spillovers.

Figure 1. World map highlighting endemic African regions and non-endemic countries affected during the 2022–2023 outbreak.

Historical Origins and Changing Patterns

The virus was first identified in 1958 during pox-like outbreaks in captive monkeys used for research, which led to the name “monkeypox.” However, subsequent research showed that rodents—particularly Gambian pouched rats and squirrels—are the most likely natural reservoir. In 1970, the first human case was confirmed in a 9-month-old child in the Democratic Republic of Congo [1].

Originally confined to remote forested areas, Mpox outbreaks were rare and typically self-contained. But in 2003, it appeared in the United States via imported animals. Then, beginning in 2017, Nigeria saw a dramatic resurgence of the virus. By 2022, Mpox had spread across Europe, the Americas, and Asia, leading the World Health Organization to declare it a Public Health Emergency of International Concern (PHEIC) [2].

Figure 2. The timeline traces Mpox from its discovery in 1958 to the most recent outbreaks in 2024.

Transmission and Public Health Importance

Mpox is a zoonotic disease caused by the Mpox virus, a double-stranded DNA virus from the Orthopoxvirus genus, the same group that includes smallpox. Transmission occurs through direct contact with infected animals, their fluids, or meat. Once introduced into the human population, it can spread from person to person through close contact, respiratory droplets, or contaminated objects like bedding or clothing.

The 2022–2023 outbreaks emphasized how modern patterns of urbanization, travel, and global interconnectedness can facilitate the spread of once-localized diseases. Though Mpox is not classified as a sexually transmitted infection, skin-to-skin contact during sexual activity—especially among networks of men who have sex with men—was a significant factor in recent global transmissions [3].

Clinical Presentation and Disease Course

Mpox begins with an incubation period of 5 to 21 days. Early symptoms resemble those of other viral illnesses and include fever, intense headache, fatigue, back pain, and notably, swollen lymph nodes—a distinguishing feature from diseases like smallpox and chickenpox. Within one to three days of fever onset, a rash appears, usually starting on the face and progressing to other parts of the body.

The rash evolves through several stages: macules, papules, vesicles, pustules, and scabs. Lesions can be few or widespread and are often painful. In most cases, symptoms resolve in 2 to 4 weeks without specific treatment. However, severe complications can occur, especially in immunocompromised individuals, children, and pregnant women. Reported complications include secondary bacterial infections, encephalitis, sepsis, and ocular damage leading to vision loss [4].

Figure 3. Visual sequence of Mpox rash development on a human body.

Diagnostic and Laboratory Approaches

Because the clinical presentation overlaps with other skin conditions, laboratory confirmation is critical. Polymerase Chain Reaction (PCR) testing is the most reliable method, typically performed on lesion swabs. While serological tests exist, their utility is limited due to cross-reactivity with other orthopoxviruses and prior smallpox vaccination [5]. Unfortunately, diagnostic capacity in many African countries remains inadequate, creating delays in confirmation and barriers to effective outbreak response.

Treatment Options and Preventive Tools

There is no specific, universally available antiviral treatment approved solely for Mpox. Most patients recover with symptomatic care, but in certain cases, antiviral agents like Tecovirimat (TPOXX) have been used under expanded access protocols. Tecovirimat has shown efficacy in vitro and in animal models and is currently recommended by WHO for severe cases or those at risk of complications [6].

Preventive strategies rely heavily on vaccination. The first-generation smallpox vaccines provided cross-protection but are no longer widely available. Modern third-generation vaccines like JYNNEOS (also known as Imvamune or Imvanex), a non-replicating vaccine, have been deployed in high-risk populations. Public health efforts in recent outbreaks included ring vaccination and targeted outreach to high-transmission networks [7].

Figure 4. The JYNNEOS vaccine, originally developed for smallpox, has been widely used in Mpox outbreak response.

Mpox in Africa and Ethiopia's Vulnerability

Africa continues to bear the brunt of the Mpox burden. The Democratic Republic of Congo and Nigeria report hundreds to thousands of suspected or confirmed cases annually. However, due to weak surveillance systems, underreporting is widespread. In 2024 alone, over 29,000 suspected Mpox cases and nearly 800 deaths were reported across the continent [8].

Until recently, Ethiopia had not faced large-scale outbreaks, but this changed in May 2025, when the first confirmed Mpox cases were reported in Moyale, a border town in southern Ethiopia. The initial cases involved a 21-day-old infant and the mother, with likely transmission linked to the infant's father who had traveled across the Ethiopian-Kenyan border. As of June 2025, the country has documented 18 confirmed cases, including one death, with active isolation measures underway [9,10].

These events highlight Ethiopia's growing vulnerability due to its porous borders, mobile populations, and increasing cross-border disease transmission. Most rural health centers still lack adequate diagnostic capacity, personal protective equipment, and outbreak-ready training. Compounding this are myths and stigma around skin diseases, leading to delays in care-seeking. For Ethiopia, investing in community engagement, risk communication, and integrated surveillance—especially under the One Health framework—is essential for effective preparedness and prevention.

Global Lessons and the Path Ahead

The global response to Mpox has highlighted ongoing inequities in the distribution of health resources. African scientists had been reporting increasing case numbers and warning of the disease’s spread long before the 2022 outbreak reached the West. However, investment in vaccine access, research, and diagnostics only surged once wealthier nations were affected. This pattern reflects the persistent neglect of diseases that primarily impact low-income regions.

Mpox offers an opportunity to reframe the global conversation around epidemic preparedness. Future interventions must emphasize equitable access to countermeasures, community-based surveillance, and African-led research agendas. For countries like Ethiopia, building resilient systems that can detect and respond to zoonotic threats at their source is critical—not only for local health security but also for global pandemic prevention.

Figure 5. African epidemiologists and lab scientists working with Mpox data and samples.

References

1. Ladnyj ID, Ziegler P, Kima E. A human infection caused by monkeypox virus in Basankusu Territory, Democratic Republic of the Congo. Bull World Health Organ. 1972;46(5):593–597.

2. World Health Organization. WHO Director-General declares the ongoing monkeypox outbreak a Public Health Emergency of International Concern. 2022 Jul 23. Available from: https://www.who.int/news/item/23-07-2022-who-director-general-declares-the-ongoing-monkeypox-outbreak-a-public-health-event

3. Thornhill JP, Barkati S, Walmsley S, Rockstroh J, Antinori A, Harrison LB, et al. Monkeypox virus infection in humans across 16 countries — April–June 2022. N Engl J Med. 2022;387(8):679–691.

4. Centers for Disease Control and Prevention (CDC). Mpox signs and symptoms. 2023. Available from: https://www.cdc.gov/poxvirus/mpox/symptoms.html

5. Adler H, Gould S, Hine P, Snell LB, Wong W, Houlihan CF, et al. Clinical features and management of human monkeypox: a retrospective observational study in the UK. Lancet Infect Dis. 2022;22(8):1153–1162.

6. World Health Organization. Clinical management and infection prevention and control for monkeypox: interim rapid response guidance. 2022. Available from: https://www.who.int/publications/i/item/WHO-MPX-Clinical-and-IPC-2022.1

7. U.S. Food and Drug Administration. FDA approves JYNNEOS vaccine for prevention of monkeypox. 2022. Available from: https://www.fda.gov/vaccines-blood-biologics/jynneos

8. World Health Organization (WHO). Multi-country outbreak of mpox, External Situation Report #28 – 2024. Geneva: WHO; 2024. Available from: https://www.who.int/publications/i/item/mpox-sitrep-2024

9. Ethiopian Public Health Institute. Mpox outbreak press statement. Addis Ababa: EPHI; May 2025. Available from: https://ephi.gov.et

10. WHO Ethiopia. Ethiopia confirms Mpox cases in Moyale district. WHO Africa Region; June 2025. Available from: https://www.afro.who.int

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