test tubes with liquid being dispensed in. A microscope
Julie Hambleton
Julie Hambleton
June 1, 2023 ·  4 min read

Disease X is coming, and with it the next global pandemic, scientists warn

As the world continues to grapple with the aftermath of a nearly three-year-long COVID-19 pandemic, scientists are warning of a new threat on the horizon: Disease X. This hypothetical disease is not yet known to exist, but experts believe it is only a matter of time before it emerges and causes the next global pandemic.

What is Disease X?

Disease X is a term coined by the World Health Organization (WHO) to describe a hypothetical disease that could cause a future pandemic. It is not a specific disease but rather a placeholder for an unknown pathogen that has the potential to spread rapidly and cause widespread illness and death. (1)

According to the WHO, Disease X could be caused by a virus, bacteria, or other pathogen that is currently unknown to science. It could emerge naturally or be the result of bioterrorism or laboratory accidents. Currently, scientists estimate that there are 1.67 million unknown viruses in mammals and birds. They predict that half of these could end up infecting humans – just as the COVID-19 pandemic began.

“(Disease X represents) knowledge that a serious international epidemic could be caused by a pathogen currently unknown to cause human disease,” wrote the WHO as far back as 2018. (2)

Why are Scientists Concerned?

The COVID-19 pandemic has shown us just how devastating a global pandemic can be. As of August 2021, the virus has infected over 200 million people and caused over 4 million deaths worldwide. The pandemic has also had far-reaching social and economic impacts, disrupting daily life and causing widespread unemployment and economic hardship.

Scientists believe that Disease X could be even more deadly and contagious than COVID-19. It could spread more rapidly and have a higher mortality rate, causing even more deaths and economic disruption.

“It is not an exaggeration to say that there is potential of a Disease X event just around the corner,” says Pranab Chatterjee, researcher at the Department of International Health at Johns Hopkins Bloomberg School of Public Health in Baltimore. “The recent spate of H5N1 bird flu cases in Cambodia is just a case in point.”

How Can We Prepare for Disease X?

Preparation is key to preventing and mitigating the impact of a future pandemic. Governments and public health organizations must work together to develop strategies for identifying and containing emerging diseases.

“Nature is producing new viruses all the time … What we’re trying to say (with Disease X) is, let’s think creatively about designing vaccines and therapeutics and drugs that not only affect known agents but also can affect future and emerging pandemic pathogens.” says Peter Daszak, president of EcoHealth Alliance, a New York-based global environmental non-profit organization.

One important step is to invest in global surveillance systems that can detect new diseases as soon as they emerge. This requires collaboration between countries and the sharing of data and resources. Scientists agree that, like COVID-19, Disease X is likely to be zoonotic, meaning that it will start in an animal host and be transferred to humans. This is important information when developing a vigilance strategy.

R&D Is Key

Another important strategy is to invest in research and development of vaccines and treatments for emerging diseases. This can help to speed up the development of effective treatments and vaccines when a new disease emerges. The scientists say that of the 1.67 million unknown viruses belong to about 25 viral families. Out of those families, they have identified 120 potentially problematic viruses for humans.

It is not possible for researchers to prepare for 120 potential viruses. What they are doing, however, is they have developed a strategy to identify prototype (model) viruses from these families that can potentially cause the greatest risk to humans and for which there are no known medical countermeasures. From there, they can preemptively develop diagnostics, antivirals, and vaccines for those prototypic viruses and then work on ways to find transferable solutions for similar ones.

“With the resources and technologies we have now, I don’t think it’s too much to ask to be ready for 120 different viruses … so, I just think it’s a call to action to have much more investment in basic research, and preparedness and understanding of biology and understanding of the threats,” Graham says.

Daszak agrees, adding that it is also not hard to predict where these outbreaks are likely to start. These are usually countries with diverse wildlife and are warmer in climate – typically tropical and sub-tropical nations. Land usage change, such as deforestation, population growth, and wildlife trade then cause humans to become in contact with these viruses.

Protecting Yourself

Finally, individuals can take steps to protect themselves and their communities from disease. This includes practicing good hygiene, such as washing hands frequently, covering coughs and sneezes, and getting vaccinated against known diseases. It is also important to avoid contact with wild animals and their excrement and not eat undercooked meat. Finally, it is important for individuals to inform themselves about diseases that are prevalent in the area they are traveling to or living in.

The Bottom Line

The threat of Disease X is a reminder that pandemics are not a thing of the past. As the world continues to become more interconnected, the risk of emerging diseases spreading rapidly and causing a global pandemic only increases.

It is up to all of us to take steps to prepare for and prevent the next pandemic. By investing in global surveillance, research, and individual prevention measures, we can work together to protect ourselves and our communities from the devastating impact of Disease X.

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  1. Disease X: A hidden but inevitable creeping danger.” NCBI. Muhammad Junaid Tahir,et al. July 26, 2021.
  2. Disease X is coming, and with it the next global pandemic, scientists warn.” National Post. Bhargavi Duvvuri. May 21, 2023.