Monkeypox virus
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The ongoing spread of mpox across African borders has prompted the World Health Organization (WHO) to declare the virus a “Public Health Emergency of International Concern” (PHEIC). The WHO has only ever issued seven PHEICs, the most recent of which was in 2022 for a different mpox strain believed to be less dangerous than the one now causing alarm. The one before that was for SARS-CoV-2 in 2020. 

Cases of mpox have been increasing in the Democratic Republic of the Congo (DRC) and neighboring African countries, including several that had never reported mpox cases before. According to WHO officials, there have been approximately 50 confirmed cases and more suspected cases in Burundi, Kenya, Rwanda, and Uganda.

Of the 15,600 cases reported in the DRC this year—roughly equal to the total number of cases reported in the country last year and dwarfing the numbers reported in 2022—70% were reported in children under 18. Experts believe the higher number of cases and deaths among children is due to a lack of protection from the smallpox vaccine, which was discontinued after the related virus was eradicated in 1980, as well as the fact that approximately 40% of children in the region are malnourished, making it more difficult for their bodies to fight the virus.

The WHO’s designation of the PHEIC for mpox is meant to prompt member countries to prepare for the virus’s appearance and share vaccines, treatments, and other key resources with poorer nations. The declaration by WHO director-general Tedros Adhanom Ghebreyesus, PhD, on Wednesday, was preceded by an announcement by the Africa Centres for Disease Control and Prevention on Tuesday declaring mpox a public health emergency of continental security, mobilizing resources across the continent—the first time the organization has ever done so.

New emerging mpox clade

The initial human case of mpox, a zoonotic disease caused by an orthopoxvirus previously known as monkeypox that has been described as a milder version of smallpox, was reported in the Democratic Republic of the Congo in 1970. Today, nations in West and Central Africa are endemic to the disease. Yet, the surge is partly due to weaknesses in the surveillance system, according to infectious disease physician Dimie Ogoina, who discovered the origin of the monkeypox outbreak in 2022 and is the chair of the emergency committee convened by WHO.

There are currently three variants of the mpox virus spreading throughout Africa. The type of mpox spreading in the DRC’s east—particularly among sex workers and other adults—and into some of the neighboring countries is a new subtype called clade Ib. It’s also the first time clade Ib has been spread through sexual transmission. However, it also seems less fatal than the original clade I circulating elsewhere in the DRC. The DRC is also recording cases of what has been called clade I (but has now been referred to as clade Ia), as is the Central African Republic. According to the WHO, Clade II has been reported in Cameroon, Ivory Coast, Liberia, Nigeria, and South Africa.

Both clades I and II can spread through direct contact with infected wild animals, through close contact (including intimate or sexual contact) with a person with mpox, and through contact with contaminated materials. Clade Ib is spreading from person to person, often via sexual contact, but also through other physical and face-to-face contact or via contaminated bedding or towels. The WHO recommends a polymerase chain reaction (PCR) as the gold standard for mpox testing in laboratories using specimens from the rash—skin, fluid, or crusts. Antigen and antibody detection methods may not be helpful as they do not distinguish between orthopoxviruses. 

During the last mpox-related PHEIC in 2022, two vaccines emerged: Bavarian Nordic’s JYNNEOS, also known as Modified Vaccinia Ankara-Bavarian Nordic (MVA-BN), and KM Biologics’ LC16 from Japan. Both are based on weakened vaccinia virus strains used as a vaccine against smallpox and mpox. JYENNOS has been approved for use against mpox by the U.S. Federal Drug Administration (FDA) and the European Medicines Agency (EMA). Outside clinical trials, neither has been available in Congo or across Africa, where the disease has been endemic for decades. Congo’s regulators approved the domestic use of the vaccines in June. Still, the government has yet to officially request any from manufacturers or governments, like the U.S., which is looking to make donations through the Global Alliance for Vaccines and Immunization (Gavi).

Insufficient mpox vaccine supply 

Last week, the WHO’s director-general began the procedure for the emergency use listing of mpox vaccines. This will speed up getting the vaccines to lower-income countries that have not yet issued their own medical clearance. The WHO is collaborating with vaccine manufacturers and nations on possible vaccine donations to ensure everyone has fair access to vaccines, treatments, diagnostics, and other tools. It constantly communicates with its partners through the interim Medical Countermeasures Network.

The EU’s Health Emergency Preparedness and Response Authority (HERA) will procure and donate 175,420 doses of the JYNNEOS vaccine to immediately respond to the mpox outbreak. In addition, the pharmaceutical company Bavarian Nordic will donate 40,000 doses of JYNNEOS to HERA. The Africa CDC will distribute the vaccines according to regional needs.

According to a statement from the U.S. Agency for International Development (USAID), the DRC has received $10 million and 50,000 doses of the mpox vaccine. This amount and contributions from Japan and the European Union bring the total number of vaccines available to approximately 200,000. But that is just 2% of the 10 million doses needed of a vaccine that costs $100 per dose, stated Jean Kaseya, director-general of Africa CDC.

The $10 million is a slice of the $424 million total pledged by the U.S. last week for the mpox situation in the DRC. The remaining $414 million is for humanitarian assistance to support people experiencing persistent humanitarian needs resulting from conflict and displacement. Of that, USAID will use $170 million in Commodity Credit Corporation funding from the Department of Agriculture (USDA) to purchase, ship, and distribute surplus agricultural commodities from American farmers to provide life-saving food assistance in the DRC. The additional health assistance will be invested across a range of critical public health interventions in response to the mpox outbreak in the region.

To allow for an immediate scale-up, WHO has released US $1.45 million from the WHO Contingency Fund for Emergencies and may need to release more in the coming days. But that’s just a start, as the WHO seeks funding from donors to cover the full extent of the needs required to respond to mpox. The US Department of Human Health Services (HHS) said it encourages US citizens at high risk to get vaccinated with the JYNNEOS mpox vaccine, which has been proven safe and highly effective at preventing severe disease from mpox. Those who have already had clade II mpox or are fully vaccinated against mpox are expected to be protected against severe illness from clade I mpox.

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