The Hindu: Published on 14th Dec 2024:
Why in News?
The hypothetical concept of Disease X has gained attention after a recent outbreak in the Democratic Republic of Congo (DRC) in December 2024, which claimed over 400 lives. Although unclassified, the outbreak highlights the risks associated with unknown pathogens and the importance of preparedness for future pandemics.
The Story So Far:
Disease X was introduced by the World Health Organization (WHO) in 2018 as a placeholder for unknown pathogens that could trigger a devastating global epidemic or pandemic.
The term became relevant during the COVID-19 pandemic, which exemplified the characteristics of Disease X — an unpredictable, novel threat.
The recent DRC outbreak has reignited concerns about the unpredictability of emerging diseases and the need for global preparedness.
WHO’s Priority List of Pathogens:
The WHO priority list, published in 2018, identifies diseases with high epidemic/pandemic potential and insufficient medical countermeasures.
The list includes:
Ebola virus disease
Marburg virus disease
Lassa fever
Nipah virus
Rift Valley fever
Crimean-Congo haemorrhagic fever
Zika virus
Disease X
This list is strategic for focusing global resources on the most serious infectious threats.
What is Disease X?
Disease X is a hypothetical placeholder for an as-yet-undiscovered pathogen that could trigger a global health crisis.
It acknowledges “known unknowns” (predictable but poorly understood threats) and “unknown unknowns” (completely unpredictable threats).
Disease X could be caused by:
Viruses, bacteria, parasites, fungi, or prions (misfolded proteins causing neurological diseases).
Approximately 70% of emerging diseases since 1940 have been zoonotic, transmitted from animals to humans due to deforestation, wildlife encroachment, and agriculture intensification.
Patterns in Emerging Diseases
Many diseases (HIV, SARS, MERS, Ebola) emerged due to ecological disruptions caused by human activities:
Deforestation
Urbanisation
Climate change
Over 1.7 million undiscovered viruses exist in wildlife, hundreds of which could infect humans.
Regions with high biodiversity and weak healthcare systems, like the Congo Basin, are particularly vulnerable.
Modern globalisation, including frequent international travel and trade, increases the risk of local outbreaks escalating into pandemics.
Challenges of Predicting Disease X.
Disease X is unpredictable as its emergence depends on multiple unknown factors:
Zoonotic spillovers (e.g., SARS, COVID-19)
Pathogen mutations that evade treatments
Laboratory accidents or deliberate biological attacks
Climate change further reshapes disease transmission patterns, allowing pathogens to adapt to new hosts and regions.
Despite advances in genomic sequencing and AI, predicting the origin and behavior of Disease X remains difficult.
Conditions driving pandemics like COVID-19 still persist, making Disease X a matter of when, not if.
Need for Global Collaboration.
Combating Disease X requires international cooperation:
WHO initiatives like the priority pathogens list and the proposed Pandemic Treaty foster unified global responses.
Frameworks like the Nagoya Protocol can ensure equitable sharing of resources, including pathogens and medical countermeasures.
Data sharing, pooled resources, and equitable access to vaccines, diagnostics, and treatments are critical for preparedness.
Organizations like the Coalition for Epidemic Preparedness Innovations (CEPI) invest in adaptive platforms that can target unknown diseases within 100 days of identification.
Conclusion:
The DRC outbreak serves as a wake-up call, reinforcing the need for:
Strengthened surveillance systems.
Investment in healthcare infrastructure.
Global solidarity and collaboration.
The unpredictable nature of Disease X demands urgent action to safeguard humanity from future pandemics. A novel disease anywhere is a threat to everyone.
