Monkeypox: A Persistent Threat?
What makes this outbreak more concerning from previous years, and what is its likelihood of developing into a pandemic?
Earlier this summer, the World Health Organisation (WHO) announced a global health emergency. Since then, international headlines have been flooded with news of a new Mpox (monkeypox) outbreak, which has surged in the Democratic Republic of Congo (DRC) and several other countries in Africa, where cases had never been seen before.
Mpox is a rare infectious disease caused by the monkeypox virus (MPXV), a species of the genus Orthopoxvirus. Those infected with the virus experience flu-like symptoms (fever, headache, muscle aches, fatigue, and swollen lymph nodes) accompanied by a skin rash or mucosal lesions that last two to four weeks. It can be transmitted by close contact with the bodily fluids or lesions of an infected human or animal, as well as human-to-human transmission via respiratory droplets and sexual contact.
The WHO declared the escalating global Mpox outbreak a Public Health Emergency of International Concern (PHEIC) from 2022 to 2023 and again in 2024.
What makes this outbreak more concerning from previous years, and what is its likelihood of developing into a pandemic?
The ongoing threat of Monkeypox
The recent upsurge in Mpox cases has been a significant cause of concern for public health officials worldwide. An increasing number of cases have been reported in the United States, Canada, the United Kingdom, and some European countries. Between January 2022 and August 2024, more than 120 countries have documented cases of Mpox, with over 100,000 laboratory-confirmed cases and more than 220 deaths among those confirmed cases.
The ongoing spread of the virus can be attributed to a combination of factors, including increased testing, improved surveillance, and the virus's ability to evade immunity. Studies have found that the monkeypox virus is evolving and mutating, which poses a challenge to acquired immunity and can potentially impact the effectiveness of vaccines.
Clade I and II: a complicating factor
There are two clades of MPXV: Clade I and Clade II. Clade I is the most severe form of the disease, with subtypes Ia and Ib. It is more contagious than Clade II and leads to severe illness and, in some cases, death. Clade II, a milder form of the disease, caused the 2022 Mpox outbreak.
Clade Ib is the most recent cause for concern as it is behind the most recent monkeypox outbreak. This variant behaves differently from other types of the virus—it spreads mainly via human contact and has a faster rate of transmission. Cases with Clade Ib have been identified in the DRC and neighbouring countries in Africa but have not been detected outside the continent.
Potential for a pandemic
With the emergence of new virus variants, researchers are finding it increasingly important to understand the spread of this virus in order to curb its transmission. However, the current Mpox outbreak cannot be compared to the COVID-19 pandemic as the rate of transmission is significantly lower. The likelihood of it evolving into a pandemic is low.
What happens next?
The recent surge in Monkeypox cases has posed a significant threat to global public health. While the situation has stabilised in recent months, the potential for future resurgences and the emergence of more contagious variants remains a concern. Notably, the emergence of Clade Ib has raised concerns due to its potential to evade immunity and impact vaccine effectiveness. The continued coordination of international efforts in surveillance, testing, and vaccine development remains crucial in addressing this persistent threat.
For more information on the current Mpox outbreak and the potential for vaccine development, read this article.