What is Disease X and why the world should prepare for it

Context: The recent outbreak
reported in the first week of December 2024 in the Democratic Republic of
Congo, which has claimed over 400 lives and remains unclassified, has raised
concerns that it could be an instance of Disease X. Disease X is not an actual
but a hypothetical disease. The World Health Organization (WHO) coined the term
in 2018 to describe an unknown pathogen that could potentially unleash a devastating
epidemic or pandemic. It was conceptualised by the WHO to prepare for future
outbreaks that are difficult to predict or identify.

Key points

·       Origin: The term "Disease
X" emerged after the West African Ebola epidemic (2014–2016), which
exposed gaps in global epidemic readiness. It embodies "known
unknowns" (threats we are aware of but lack specifics) and "unknown
unknowns" (threats beyond our awareness). The concept underscores the
inevitability of new pathogens and emphasizes proactive preparation.

·       Epidemiological
Patterns: Since 1940,
over 300 emerging infectious diseases have been identified, with 70% having
zoonotic origins (transmitted from animals to humans). Human activities such as
deforestation, urbanization, and climate change exacerbate these risks,
bringing wildlife and humans into closer contact. Regions with high
biodiversity and limited healthcare infrastructure, such as the Congo Basin,
are particularly vulnerable.

·       Challenges
in Prediction: Predicting Disease X is challenging due to:

Ø  The vast number of
undiscovered pathogens.

Ø  Increasing zoonotic
spillovers driven by human encroachment.

Ø  Climate change altering
disease dynamics and expanding vectors like malaria and dengue.

Ø  Risks from antimicrobial
resistance, bioterrorism, and accidental lab leaks.

·       Global
Preparedness and WHO’s Priority List: The WHO's priority pathogen list includes diseases
like Ebola, Marburg, Nipah, and Disease X. This list aims to direct global
research, funding, and policy efforts toward combating high-risk diseases with
limited medical countermeasures.

Ø  Strengthening Surveillance - Robust systems for early
outbreak detection are critical. Technologies like genomic sequencing and
real-time data sharing play pivotal roles.

Ø  Healthcare Infrastructure - Low- and middle-income
countries require enhanced healthcare systems to mitigate the disproportionate
impact of pandemics.

Ø  Rapid Response Platforms - Organizations like the
Coalition for Epidemic Preparedness Innovations (CEPI) are developing
"prototype pathogen" platforms to create vaccines within 100 days of
identifying a new disease.

·       Need for
Global Collaboration: Pandemics transcend borders, necessitating unified global efforts:

Ø  WHO Initiatives - Efforts like the Pandemic
Treaty aim to standardize global responses.

Ø  Equitable Access - Frameworks like the Nagoya
Protocol ensure fair distribution of resources and medical countermeasures.

Ø  International Cooperation - Governments must share
data, pool resources, and collaborate on diagnostics, treatments, and vaccines.