Disease X: What Do We Know? Not Much, And That Is The Problem

Disease X is on the list of "priority diseases" on the WHO website, along with Zika, Nipah and Ebola, among others.

Disease X: What Do We Know? Not Much, And That Is The Problem

Climate change, urbanisation and the destruction of forests add to the risk of pandemics.

A UK health expert's warning that a new pathogen could cause a pandemic as deadly as the Spanish Flu - which killed 50 million people - has sent alarm bells ringing in a world that is yet to completely emerge from what it hoped was a once-in-a-lifetime event -- Covid-19

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Disease X is on the list of "priority diseases" on the WHO website, a roll call that also includes the Ebola virus disease, Middle East respiratory syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS), Nipah and Zika. These are all diseases that have a high fatality rate. The list was first published in 2017. 

What Is Disease X 

According to the WHO website, Disease X "represents the knowledge that a serious international epidemic could be caused by a pathogen currently unknown to cause human disease". The pathogen could be a virus, a bacterium or a fungus. 

In essence then, it serves as a warning that the next pandemic could be lurking around the corner and it is very difficult to predict what could cause it. It also helps direct research and investment towards emerging diseases and is meant to aid in the quick development of vaccines.

"Targeting priority pathogens and virus families for research and development of countermeasures is essential for a fast and effective epidemic and pandemic response. Without significant R&D investments prior to the Covid-19 pandemic, it would not have been possible to have safe and effective vaccines developed in record time," a release quoted Dr Michael Ryan, Executive Director of WHO's Health Emergencies Programme, as saying.

What The Expert Said

In an interview to the Daily Mail, Kate Bingham, who served as the chair of the UK's Vaccine Taskforce from May to December 2020, said the new virus could have a similar impact to the devastating Spanish Flu of 1919-1920.

 "Let me put it this way: the 1918-19 flu pandemic killed at least 50 million people worldwide, twice as many as were killed in World War I. Today, we could expect a similar death toll from one of the many viruses that already exist," she said. 

"In a sense, we got lucky with Covid-19, despite the fact that it caused 20 million or more deaths across the world. The point is that the vast majority of people infected with the virus managed to recover... Imagine Disease X is as infectious as measles with the fatality rate of Ebola. Somewhere in the world, it's replicating, and sooner or later, somebody will start feeling sick," Ms Bingham told the Daily Mail.


The WHO's R&D Blueprint is a global strategy and preparedness plan that allows the rapid activation of research and development activities during epidemics. It is meant to to fast-track the availability of effective tests, vaccines and medicines that can be used to save lives and avert large-scale crises, according to the WHO website.

For each disease an R&D roadmap is created, followed by target product profiles. The roadmap is then used to guide the response to outbreaks in both urgent action and in developing ways to improve the global response for future epidemics.

Pandemics Increasing?

While the origins of Covid-19 aren't 100% clear, it is believed to be a zoonotic disease which first infected a human in Wuhan, China, through a bat or some other animal. 

As per the National Center for Biotechnology Information (NCBI) in the United States, the potential for diseases to spread and escalate into epidemics or pandemics is increasing. The reasons cited for this include globalisation and the increased flow of humans and goods to all parts of the world.

The other reasons include urbanisation and the fact that, in many parts of the world, people are clustered together and living in overcrowded and unhygienic environments in which infectious diseases can thrive. The destruction of forests is also seen as a big danger.

The NCBI cites climate change, increased human-animal contact, and a shortage of health workers as the other reasons. The last of these is important because trained health workers can help identify and contain diseases before they spread, but they are usually lacking in places where such epidemics originate.