Disease X: WHO Puts Potential Disease On Priority List, Warns Of Possible 'Serious International Epidemic'

Lorenzo Tanos

The World Health Organization recently released the results of its second annual review of prioritized diseases and revealed the possibility that an illness simply known as "Disease X" could eventually pose a public health threat.

In a news release published this week, the WHO updated its list of "R&D Blueprint" priority diseases, which were chosen last month for their potential to "cause a public health emergency," and the fact that these illnesses do not have any known cures or vaccines. Out of several known illnesses taken under consideration, the WHO listed the Ebola virus disease, Rift Valley fever, Zika, Middle East respiratory syndrome coronavirus (MERS-CoV) and Severe Acute Respiratory Syndrome (SARS). However, the inclusion of the so-called "Disease X" stood out in the priority list, due to the lack of concrete information on the potential disease-causing pathogen.

"Disease X represents the knowledge that a serious international epidemic could be caused by a pathogen currently unknown to cause human disease, and so the R&D Blueprint explicitly seeks to enable cross-cutting R&D preparedness that is also relevant for an unknown 'Disease X' as far as possible," wrote the WHO.

Although the WHO's news release did not explicitly mention a possible source for the mystery disease, should it exist, News.com.au cited the health agency in writing that there might be other explanations for the illness, aside from contact with diseased animals, such as in the cases of Zika and chikungunya, which is passed on by mosquitos, and various forms of influenza passed on by birds, swine, and other animals. These include the increasing use of chemical warfare in various applications, as well as the possibility of a man-made disease that might have been created via gene editing techniques.

"The point is to make sure we prepare and plan flexibly regarding vaccines and diagnostic tests," said Rottingen, as quoted by News.com.au.

While several publications focused on highlighting the possible worst case scenarios should a Disease X epidemic break out, the WHO's news release instead stressed the importance of research and development, and constant vigilance ahead of the next annual review, regardless of the prioritized disease in question. The agency noted the importance of a "One Health" approach, which the One Health Global Network website describes as a paradigm wherein people's health and well-being is promoted "through the prevention of risks and mitigation of effects" related to diseases that may be passed between animals and humans in their respective ecosystems, and, as the WHO noted in a separate article, fighting antibiotic resistance.