The ampox outbreak in Africa is another example of how infectious diseases that are considered “someone else’s problem”, and which mainly affect poor, developing countries, can suddenly pose an unexpected global threat.
Other examples of neglected diseases include West Nile, Zika, and chikungunya viruses.
Ampox was discovered in 1958 (in captive monkeys, hence its original misnamed “monkeypox”) and the first human case was identified in 1970. For decades thereafter it was largely neglected by the scientific and public health communities, considered an uncommon infection endemic to remote rural areas of tropical Africa, of no significance to the rest of the world.
When a massive outbreak of ampox hit developed countries in 2022, an increase in research funding led to a surge in scientific studies. On just one medical search engine, more research has been done since April 2022 than in the previous 60 years.
The global ampox outbreak in 2022–23 occurred despite repeated calls by African researchers to increase global investment in diagnostic, therapeutic and infection prevention tools for ampox.
The World Health Organisation has now declared the growing outbreak of ampox in Central Africa a public health emergency of international concern.
This is the highest alert level for events that pose a public health risk to other countries and require a coordinated international response.
We are infectious disease researchers who have worked on HIV, SARS-CoV-2, and other viral infections.
The recent history of ampox is a reminder that an infectious disease in one corner of the world should not be viewed as someone else’s problem, because it can suddenly begin to spread rapidly and far and wide.
It also highlights global inequalities in resource allocation and access to vaccines, diagnostics and treatments. These were made available in many industrialised countries and helped contain the global outbreak, but are still lacking in much of Africa.
The 2022 outbreak: A complete surprise
The disease has been renamed “mpox”, but the virus remains called “monkeypox” (MPXV). It is very similar to the smallpox virus.
MPXV was thought to be a zoonotic disease endemic to parts of central and western Africa. It spread mainly through close contact with wild mammals, especially handling bush meat, but there was no known human-to-human transmission.
Cases have been reported only occasionally outside endemic areas, due to the importation of infected travellers or infected small mammals.
This changed abruptly in 2022: a massive, rapidly evolving global outbreak led to more than 99,000 laboratory-confirmed cases in 116 countries. At its peak in August 2022, more than 6,000 cases were reported each week.
This outbreak was completely surprising: most cases were reported from non-endemic countries, mostly in men who had sex with men who had recently become infected during sexual relations.
Although most cases were not clinically particularly severe and the mortality rate was just over 200, the global outbreak was declared a public health emergency of international concern by the World Health Organization on 23 July 2022.
Fortunately, a combination of behavioral changes and vaccinations in at-risk groups soon led to a sharp decline in the number of cases.
Modern vaccines and antiviral drugs active against ampox have become available in many affected high-income countries.
These were developed and stockpiled in the US and Europe, primarily in preparation for a possible biological weapon attack using poxviruses.
The global outbreak in 2022 was caused by clade II of MPXV, which is endemic to West Africa and is not as virulent as clade I MPXV, which has so far been seen only in the Congo Basin.
The first ampox public health emergency of international concern was declared over in May 2023.
Clade II MPXV infections are still occurring globally, but the worst is now over.
Complacency would be a misguided move, as the current growing ampox outbreak shows.
Emergence in Africa
The African region is expected to see a surge in ampox cases, beginning in 2023.
Africa is a continent that includes areas where ampox has long been endemic, and it now presents a complex mosaic:
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Cases arising from endemic, largely zoonotic, patterns that used to be dominant in the past
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Cases linked to the 2022 global outbreak, for example in South Africa
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Of most concern is the steady increase in the number of MPXV clade Ib infections reported from the Democratic Republic of the Congo.
New, more dangerous strain
The current Clade I MPXV (formerly called the Congo Basin strain) is more virulent than the Clade II (West African) strain, resulting in higher mortality rates.
The current outbreak is centred in the South Kivu province in eastern DRC, and has the potential to fuel a major epidemic.
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It has a distinctive epidemiological pattern, with a continuous chain of human-to-human transmission, most often via the sexual route.
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It may be that its contagiousness has increased (we don’t know that yet).
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The virus belongs to the recently defined Clade IB lineage. It displays mutations that are hallmarks of human-to-human spread that is predicted to occur from September 2023.
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The number of cases is rising rapidly, even though many suspected cases have not been tested and are therefore not counted as confirmed. Complicating matters further, a commonly used test fails to detect infections with this lineage of the virus.
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It mostly affects adults.
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The mortality rate from this pandemic is higher than that of the global outbreak of 2022.
This outbreak has already led to cases of ampox being reported in several neighbouring countries, including Kenya, where there is no prior record of ampox.
The challenge is enormous. Eastern DRC is a region beset by many problems. These include natural disasters, violence and infectious diseases endemic to the DRC such as measles, cholera and poliomyelitis.
The second-largest Ebola outbreak in recent years occurred across a wide area and posed considerable challenges, despite the availability of vaccines and treatments.
What should happen?
A recent article our co-authored in The Lancet Global Health outlines what needs to be done to contain this outbreak and prevent it from turning into an epidemic, even possibly a pandemic.
Equitable access to diagnostic tests, vaccines, and antiviral treatments requires political commitment and financial investment.
Scientific investigation is needed to learn more about exposure settings, transmission routes, and clinical presentations.
Finding the best ways to perform these interventions is important.
We propose the establishment of an African-led, multi-disciplinary, multi-country Mpox Research Consortium (MpoxREC) in Africa.
It should conduct research towards the elimination of ampox as a public health problem.
There is no doubt that a disease in one corner of the world can suddenly become a threat to global health. It is time for the global health system to understand this reality.
,Author: Wolfgang Preiser, Head: Department of Medical Virology, Stellenbosch University; Cheryl Baxter, Head: Scientific Research Support, Stellenbosch University, and Jean Nachega, Professor of Epidemiology, Stellenbosch University)
,disclosure statement: The authors do not work for, consult, hold shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.)
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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