Experts from the UK Health Security Agency (UKHSA) have highlighted four dangerous virus families that could potentially lead to a major health threat dubbed "Disease X," prompting concerns about their capacity to trigger the next pandemic.

These findings underscore the urgent need for preparedness in light of increasing viral risks.

The UKHSA has assessed 24 virus groups, categorizing their pandemic potential as high, moderate, or low based on their infectiousness, severity of disease, and the United Kingdom's vulnerability to them.

Among these, four virus families emerged as particularly concerning:

Paramyxoviridae: This family includes the variola virus, which causes smallpox, and the Nipah virus, known for its severe neurological effects, including brain swelling and death.

Picornaviridae: This family is associated with enteroviruses, which can lead to illnesses resembling poliomyelitis.

One notable virus, acute flaccid myelitis (AFM), can result in muscle weakness and paralysis.

Coronaviridae: This includes coronaviruses such as SARS-CoV-2 (Covid-19) and MERS-CoV, primarily found in the Middle East.

Orthomyxoviridae: This family includes viruses that lead to various forms of influenza, such as avian influenza (bird flu).

The UKHSA's assessment differentiates itself from other international virus risk registries by combining the known pathogenic risks along with the uncertainties surrounding them.

Certain microorganisms have received high ratings partly due to the limited research conducted on them, leading to a lack of available tests, vaccines, or treatments should they become widespread.

Antibiotic resistance in bacteria and climate change further exacerbate the risk landscape, making environments more hospitable for pathogens.

The phenomenon of zoonotic transmission, where diseases jump from animals to humans, accounts for approximately 75% of newly emerging infectious diseases.

This transmission pathway was notably the case for Covid-19, which is believed to have originated from pangolins being sold at markets in China.

The term "Disease X" is not indicative of a specific existing illness but rather a hypothetical label adopted by the World Health Organization (WHO) for a newly emerging infectious disease that could cause an epidemic or even a pandemic.

This nomenclature was established prior to the Covid-19 outbreak and was included in a list of priority diseases by the WHO in February 2018.

The WHO has developed a Research and Development Blueprint designed to facilitate rapid activation of research and development activities during epidemics, aimed at expediting the availability of effective diagnostics, vaccines, and treatments to save lives and avert large-scale crises.

In recent years, world health has been shaken by several outbreaks, including SARS, swine flu, MERS, Ebola, and Covid-19. Experts express concern that the next significant pandemic could be more severe than that caused by SARS-CoV-2.

At a panel discussion at the World Economic Forum in January 2024, WHO Director-General Dr. Tedros Adhanom Ghebreyesus emphasized the need for additional efforts to prepare health systems for the challenges posed by potential future pandemics.

He warned against dismissing the threat, stating that historical precedents illustrate the importance of forecasting possible infectious disease outbreaks.

Preventive measures are already being implemented by the WHO to address potential future infections, including the establishment of a pandemic fund and a technology transfer center in South Africa to enhance local vaccine production and address inequities in vaccine access between high- and low-income nations.

The European Centre for Disease Prevention and Control suggested in a 2022 report that efforts should focus on strengthening existing pandemic systems rather than creating new protocols.

Effective disease surveillance systems are vital for promptly detecting outbreaks before they escalate and pose severe threats to public health.

The WHO acknowledges that outbreaks can arise from pathogens not yet identified as causing human diseases.

Advancements in vaccine technology during the Covid-19 pandemic allowed for multiple vaccine options to be ready within a year, highlighting significant progress in rapid vaccine development.

Experts anticipate that future innovations will enable scientists to quickly adapt existing vaccine formulations to combat new viruses as they emerge.