OUTBREAK: Mpox

Background on Mpox

Mpox is a zoonotic infectious disease caused by the monkeypox virus (MPXV), an Orthopoxvirus belonging to the same genus as smallpox. MPXV was discovered in 1958, with the first human infection identified in 1970 in the Democratic Republic of Congo (DRC). There are two known clades of MPXV: clade I and clade II (subdivided into clade IIa and clade IIb); with clade I generally considered more virulent than clade II. 

MPXV can be transmitted human-to-human by close contact and via animal-to-human transmission occurring through direct contact with infected animals or consumption of infected, undercooked bushmeat. The natural reservoir is currently not known. Although a mild disease in most, children, pregnant women, and people with a weakened immune system are at higher risk of complications and death.

In May 2022, mpox spread beyond the eleven previously known endemic West and Central African countries and caused a global outbreak. This was driven predominantly by sexual transmission of the clade IIb MPXV and heavily affected men who have sex with men.

Current Outbreak 

In December 2022, the Democratic Republic of the Congo (DRC) declared a national outbreak of mpox. The continued development of the outbreak since then has seen the highest cases and deaths recorded in the country with geographical expansion to all 26 provinces.  Several factors beyond the rapid increase in cases make this outbreak alarming including the emergence of a novel strain (clade Ib), the suggestion of sustained human-to-human transmission, the spread of mpox to highly mobile populations and densely populated urban regions, the first documented sexual contact transmission of clade I identified with the novel clade Ib MPXV, and the spread the novel clade to neighboring non-endemic East African countries. While the past few years have seen marked increases in mpox cases in the DRC with children being the most affected, the ongoing outbreak differs in pattern and scale from those previously observed, with novel modes of transmission, and is compounded by multiple emergencies in the region, hindering an optimal response.

While clade I MPXV spreads beyond the DRC borders, clade II MPXV cases continue to circulate, re-emerge, and increase in other African countries. The mpox situation in Africa is concerning and emphasises the continued risk of clade II MPXV spread and the introduction of the apparently deadlier and novel clade Ib MPXV to additional countries within and beyond Africa. On 15 August 2024, Sweden reported the first case of clade Ib MPXV outside of Africa with associated epidemiological links to an endemic African country. In response to the escalation of events, the World Health Organization (WHO) declared the outbreak a Public Health Emergency of International Concern (PHEIC) on 14 August 2024, shortly after the Africa CDC declared a public health emergency of continental security. 

For more information about the ongoing mpox outbreak in Africa, click here

Key Public Health and Research Updates

August 2024:

• FDA approves ACAM2000 vaccine (previously used against smallpox) for use against mpox in high-risk individuals.
• Nigeria became the first country in Africa to receive mpox vaccines outside of clinical trials.
• A new specific RT-PCR test specifically designed to detect clade Ib MPXV has been developed.
• Preliminary results from PALM007 demonstrate that tecovirimat was ineffective at treating mpox lesions compared to a placebo. 
• WHO declares a Public Health Emergency of International Concern.
• Africa CDC declared a public health emergency of continental security.
• Bavarian Nordic intends to conduct a Phase 2 RCT comparing the safety and immunogenicity of the MVA-BN vaccine in adults compared with children. The trial plans to include participants from Uganda and DRC. 

July 2024:

• CEPI and CIHR have announced an additional US $4.9 million to be allocated to the clinical trial (‘SMART’) with sites in the DRC (including in South Kivu), Uganda, and Nigeria to test if MVA-BN is effective post mpox exposure. 
• WHO R&D Blueprint team published ‘Pathogens Prioritization. A scientific framework for epidemic and pandemic research preparedness’ and prioritised research for MPXV and the Poxviridae viral family as they pose a high PHEIC risk. 

June 2024:

• The Pandemic PACT team and GloPID-R Africa Hub share an updated technical briefing detailing ongoing research activity, highlighting evidence gaps, and outlining the funding landscape with the GloPID-R membership. 

May 2024:

• A Phase 3 RCT led by the Nigerian CDC and sponsored by PANTHER, aims to test the efficacy and safety of antivirals for mpox in Cameroon, Nigeria, and DRC. 
• WHO releases a ‘Strategic framework for enhancing prevention and control of mpox: 2024-2027’

April 2024:

• Genomic sequencing from South Kivu revealed a novel variant (now clade Ib) has emerged suggesting sustained human-to-human transmission. Further research is needed to understand the novel variant's transmissibility and ability to cause severe disease. 
• EDCTP announces an emergency call for proposals to support research and understanding of mpox in the DRC. 

March 2023:

• The Pandemic PACT team shares its first technical briefing with members of a highly specialised mpox meeting organised by the GloPID-R Africa Hub and the central secretariat. 

December 2022:

• The DRC declares a national mpox outbreak.

Outbreak-Specific Research Priorities 

Following a high-level emergency regional meeting on mpox, African Ministers of Health issued a communique on 13 April 2024 outlining key actions for the response to the ongoing mpox outbreak. The communique includes areas for prioritisation for R&D for an effective response. The WHO also published the 'Strategic framework for enhancing prevention and control of mpox-2024-2027' report on 24 May 2024 which includes proposed priority areas for research. 

We present analyses of mpox research activities mapped to the identified research priorities in these two documents, and we also map activities to our broader Pandemic PACT research categories. 

Relevant Links

• African Ministers of Health issued a communique
• WHO’s Strategic framework for enhancing prevention and control of mpox-2024-2027

Pandemic PACT Data

See below our data visualisations for mpox research funding, including alignment to the outbreak-specific research priorities. Visit our ‘explore’ page and filter for mpox to review the details of the research grants funded and their linked publications.