Monkeypox, the silently emerging threat


Monkeypox is not a rare disease anymore. Appropriate and effective interventions and active surveillance activities are urgently needed to make sure that monkeypox won’t become the new smallpox.


Monkeypox (caused by Monkeypox virus, genus Orthopoxvirus) has long been thought to be a rare disease occurring in humans only sporadically1. But after its “cousin” variola (causing smallpox) was eradicated in 19802 and the vaccination was stopped3, it left more people every year vulnerable to all orthopoxvirus infections. This, together with higher exposure to possibly infected animals because of anthropogenic and demographic changes in the last decades, caused a 20-fold increase in monkeypox incidence4. Today, monkeypox is endemic in the Democratic Republic of Congo (DRC) and occurs also in other countries of western and central Africa5. It already left the African continent once when rodents shipped from Ghana to the USA in 2003 caused an outbreak counting 47 cases6-8.

It is estimated that 75% of the (re-)emerging pathogens are zoonotic9 and a striking number of newly described zoonoses is linked to an expanding global population and accelerated global changes10. Drastic wildlife reduction, global climate changes, changes in agricultural practices, wildlife trade, traveling and migration of people are hot topics of the last decades which are closely linked to the (re-)emergence or introduction of a new pathogen into a population211,13. Recently we have seen such pathogens (e.g. Ebola and Zika) to emerge and cause an epidemic. So we are aware of the dangers that zoonotic pathogens constitute and we know that they will emerge and possibly cause an epidemic or pandemic more frequently in the future. Yet, we still rather spend much more money for response and control of outbreaks than less money for research and surveillance before it emerges so that we could be more prepared and possibly prevent it. Before the Ebola outbreak in 2014, there was no treatment or vaccine even though we knew about the virus since 1976. This Ebola outbreak cost more than $3,6 billion (not mentioning the lives and GDP loss of the three affected countries)14 while it is estimated that it would cost only about $3,4 billion to identify 99% of high-consequence viruses in wildlife hosts that are most likely to carry the next pandemic15.

Monkeypox outbreak reports are often incomplete because the data are nowadays acquired through a passive surveillance program. It has been shown that passive surveillance systems often miss most cases, leading to an underestimation of the burden of MPXV infections in humans4, 16. In the DRC, this is largely due to years of civil war throughout the country which has made surveillance activities, but also research on the ecology, epidemiology, natural history and pathogenesis of the infection very difficult. It means that most recent data on MPX cases are probably significantly underreported leading to underestimating the magnitude of the problem.

Monkeypox pic

Monkeypox virus currently belongs to the “biosafety level 3” category, the “high threat” biodefence category in the EU17 and is on the list of select agents in the USA18. In any of the following cases, the treat would further increase virulence increase (both naturally19,20 or genetic engineering21), virus spill into more widely distributed taxa22 or introduction in other continents4. In fact, we are probably allowing the virus to increase its virulence by not controlling its transmission, partially because of not knowing about all monkeypox cases. Moreover, an unintentional import of a disease to a new continent is nowadays fairly easy due to air transportation. And yet, there is too little research being done about the topic and not all generated data is published for various reasons. The latter is an issue limiting scientific progress in any research area but is even more pronounced in the field of neglected tropical disease where much is unknown.

Monkeypox is not a rare disease anymore. Its incidence in the DRC increased 20-fold compared to 1980s4 and some sources suggest changes in transmission rate23 and mortality rate24. Appropriate and effective interventions and active surveillance activities are urgently needed to make sure that monkeypox won’t become the new smallpox22.



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Sklenovska_pic Nikola Sklenovská is a young global health professional with a master in Biomedical Sciences. Nikola’s main interests are emerging infectious diseases. With her work, she wants to have a positive impact in the World while discovering new perspectives and ideas.


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