Mpox: A New Public Health Emergency that Concerns Us All

The African CDC has declared the ongoing Mpox outbreak (caused by the monkeypox virus) a public health emergency of continental concern. A few hours later, the World Health Organisation (WHO) declared it a public health emergency of international concern (PHEIC).

An alarming rise of cases

The declaration follows an alarming rise in the number of cases, which are spreading to an increasing number of African countries. 17,500 cases have been reported since the beginning of the year, compared with about 15,000 for the whole 2023. Most cases were concentrated in the Democratic Republic of Congo, but have recently been reported in more than a dozen African countries including Burundi, Kenya, Rwanda and Uganda.

A more transmissible strain

Another cause of concern is the evolution of the virus. Most cases in Africa are due to clade I of the virus, which is known to have a higher case fatality rate than the clade II that caused a PHEIC in 2022. Clade I is estimated to kill about 3 to 4 people per hundred infected, compared to 1 in one thousand for clade II. What has raised the alarm is that clade I, previously known to cause limited outbreaks, has evolved into a new version (clade Ib) that appears to be much more transmissible between people. Hence, the concern that it may spread beyond Africa.

How is Mpox transmitted?

The virus is transmitted by contact with infected animals (small mammals are likely a reservoir) as well as by close contact with infected people (including sexual contact) or with contaminated objects.

Is Mpox deadly?

Around 10% of Mpox infections are asymptomatic. Those that are symptomatic usually start with vague symptoms such as swelling of lymph nodes and fatigue, before developing a rash which, in children, can be mistaken with other childhood diseases. In a few cases, particularly in pregnant women, children and immunosuppressed people, the infection can be fatal. Since 2022, more than 1,400 deaths from mpox have been reported in Africa.  Many of these deaths have been children.

What can be done?

First of all, the declaration of a public health emergency in Africa is meant to step up surveillance and cooperation between countries. Access to diagnostic tests to identify and isolate infected people and survey their contacts is also crucial.

But the key to controlling the outbreak is vaccines. Unlike in the early months of the COVID-19 pandemic, there are effective vaccines against Mpox (their efficacy against clade Ib is not yet confirmed but they should provide at least some protection). The problem is their availability. Most of the available vaccine doses were purchased by high-income countries after the Mpox PHEIC was declared in 2022. Ongoing negotiations with Bavarian Nordic, the manufacturer of the vaccine, should provide an additional 200,000 doses to the continent. But this is still far short of the 10 million doses estimated to be required to stop the current epidemic.

The global health community fears that high-income countries will stockpile vaccines and treatments now that a PHEIC is declared, as happened with the COVID-19 pandemic. This is the moment to remind all countries, once again, that the best way to stop a fire from spreading is to put it out at the source instead of waiting for the flames to reach your home.