What will be the next pandemic? Be prepared for Disease X

The COVID-19 pandemic highlighted humanity’s vulnerability to emerging infectious diseases. More than five years after the coronavirus outbreak, the world is still recovering from its effects, and scientists and health organizations are already preparing for what they call “Disease X”—a hypothetical future disease that could cause the next pandemic.  

What the world learned from the COVID-19 pandemic 

The Coronavirus pandemic exposed significant weaknesses in public health systems, highlighting the critical need for preparedness and international collaboration. Many global healthcare systems struggled to cope with the sudden surge of cases, and the pandemic revealed how unprepared they were. It made clear the urgent need for stronger infrastructures capable of containing outbreaks before they spiral into global crises or tackle large-scale health emergencies effectively. 

Moreover, the pandemic demonstrated how misinformation can spread faster than the virus itself, undermining public trust and complicating adherence to screening and vaccination guidelines. The fragility of global supply chains also disrupted access to essential medical supplies and treatments, further stressing the necessity of solid and reliable distribution networks. On a positive note, COVID-19 accelerated vaccine development due to unprecedented global cooperation and innovative technologies, which were crucial in the battle against the virus. The ongoing efforts to better prepare for future pandemics can now be drawn on these experiences to address emerging diseases such as Disease X—a term the World Health Organization (WHO) uses to describe a potential future epidemic caused by a currently unidentified agent.

What Is Disease X?

Disease X isn’t a specific illness; it’s a placeholder that the WHO uses to represent a serious global epidemic that could emerge from an unknown virus or bacteria. This concept aims to establish a comprehensive strategy that includes research on DNA and RNA viruses, universal diagnostic tools, flexible vaccine platforms, and strong surveillance systems to enable the global healthcare system to develop flexible countermeasures and respond effectively to any new threats that may arise. By including Disease X in its list of priority pathogens, the WHO promotes a global proactive approach: preparing for the unexpected. 

What Could Be the Next Virus Causing a Pandemic?

While predicting the exact origin of the next pandemic is impossible, experts in clinical and diagnostic virology have highlighted several viral families that could pose a significant threat.  

• Influenza Virus. Seasonal flu is well known, but novel influenza strains—like avian or swine flu—could mutate and become highly contagious and deadly for humans. Thus, it is essential to track mutations and prepare vaccines accordingly.  

• Coronaviruses. SARS-CoV, MERS-CoV, and SARS-CoV-2 all originated in animals before spilling over into humans. As human-animal interactions increase, so does the risk of another zoonotic coronavirus outbreak. 

• Filoviruses (e.g., Ebola, Marburg). These human viruses are extremely deadly and can spread from person to person. They remain a significant concern, especially in regions with weak healthcare systems.  

• Orthopoxviruses (e.g., Monkeypox). Monkeypox showed how quickly a once-rare disease can gain global attention. Its recent spread outside Africa raised some serious alarms.  

• Unknown Pathogens. Perhaps the most alarming possibility is the emergence of a completely new virus—one that humans have never encountered before—triggered by environmental changes, overpopulation, or increased contact with wildlife. 

What Are International Institutions Doing to Prepare?

The world’s governments and international health institutions have increased efforts to prevent and prepare for future pandemics. The WHO maintains the Global Influenza Surveillance and Response System (GISRS), which continuously monitors flu strains to detect potential threats early.  It also oversees the R&D Blueprint – a global strategy that focuses on accelerating research and development in epidemics – and helps member states to strengthen their public health capacities by providing a framework for national and global disease control measures. The CDC’s Global Health Security Agenda (GHSA) assists countries in strengthening their capacity to detect, respond to, and contain disease outbreaks effectively, for example, by providing critical virology specimen collection and diagnostic virology procedure information, ensuring accurate and timely testing in case of a health emergency. Even the United Nations and the G20 have established strategies that promote health financing systems at the international level.  

Taken together, these measures reflect a growing commitment to building a more robust global health system capable of responding quickly and effectively to emerging infectious disease threats. 

What Should Be Implemented to Tackle the Next Pandemic Efficiently?  

Preparedness requires an integrated strategy involving science, technology, and societal engagement: 

• Strengthening Surveillance Systems. Real-time indicator- and event-based surveillance of outbreaks is essential for early detection. This includes utilizing AI, big data analytics, and genomic sequencing. 

• Investing in Research and Development. Funding antivirals, vaccines, and diagnostic tools that are effective across multiple pathogens will advance clinical and diagnostic virology. 

• Improving Healthcare Infrastructure. Investments in hospitals, trained staff, and supply chains are needed, especially in low- and middle-income countries. 

• Promoting Global Equity. Equitable access to vaccines, treatments, and diagnostics during a pandemic helps prevent new variants and keeps everyone safe. 

• Enhancing Public Communication. Clear, consistent, and science-based communication generates trust and improves compliance with public health measures. 

• Building One Health Approaches. Recognizing the connection between human, animal, and environmental health is vital for preventing zoonotic diseases. 

Conclusions

The next pandemic may not resemble COVID-19, but it will put our readiness to the test. With Disease X looming as a real threat, the world has no option but to act today and build a better and more flexible global health system. From supporting pioneering research to strengthening international cooperation, the path forward is clear. By learning from the past and standing prepared for the unexpected, we can confront the next pandemic with confidence and competence. 

Sources 

1. https://publichealth.jhu.edu/2024/what-is-disease-x 

1. Iserson KV. The Next Pandemic: Prepare for “Disease X”. West J Emerg Med. 2020 Jun 8;21(4):756-758. doi: 10.5811/westjem.2020.5.48215. 

1. Chiu KH, Sridhar S, Yuen KY. Preparation for the next pandemic: challenges in strengthening surveillance. Emerg Microbes Infect. 2023 Dec;12(2):2240441. doi: 10.1080/22221751.2023.2240441. 

1. Zhao M, Lei L, Jiang Y, Tian Y, et al. Unveiling the Threat of Disease X: Preparing for the Next Global Pandemic. J Med Virol. 2025 Feb;97(2):e70227. doi: 10.1002/jmv.70227.https://pubmed.ncbi.nlm.nih.gov/39570367/