The world has been grappling with the COVID-19 pandemic for several years, with its far-reaching impacts on health, economies, and daily life. Yet, scientists and public health experts warn that the next pandemic, often referred to as the ‘Big One,’ might already be silently brewing, posing an even greater threat to humanity. Among the potential culprits lurking in the background are paramyxoviruses, a family of viruses that includes notorious pathogens like mumps, measles, and respiratory tract infections. These viruses have recently gained attention for their pandemic potential, prompting concerns among researchers and policymakers.
The paramyxovirus family encompasses over 75 different viruses, each with its unique characteristics and ability to cause diseases in humans and animals. Well-known members of this family include the mumps virus, measles virus, and respiratory tract infections caused by various paramyxoviruses. In October, the National Institute of Allergy and Infectious Diseases added the paramyxovirus family to its list of pandemic pathogens to watch, signaling the growing concern within the scientific community.
One of the most alarming members of this viral family is the Nipah virus, which has the potential to infect cells that line the central nervous system and vital organs. What makes Nipah even more alarming is its high fatality rate, which can reach up to 75 percent, dwarfing the comparatively lower mortality rate of COVID-19, which stands at well under one percent.
In contrast to the flu and COVID-19, which are known for their ability to rapidly mutate, paramyxoviruses appear to be relatively stable in terms of genetic changes. However, they have evolved to become highly efficient at transmitting among humans. This unique characteristic raises concerns that, even without significant mutations, these viruses could pose a substantial threat to global health if they were to cross species and become more contagious or deadly.
Just envision a scenario where a paramyxovirus emerges with the contagiousness of measles and the deadliness of Nipah. Michael Norris, Ph.D., an assistant professor at the University of Toronto, paints a dire picture of such a possibility. This dystopian vision echoes the 2011 film “Contagion,” which depicted a lethal microbe originating from Hong Kong triggering a global pandemic—the disease in the movie was the Nipah virus.
Despite their long history of existence, paramyxoviruses remain enigmatic in many aspects. Scientists are still struggling to comprehend how these viruses jump between species and adapt to infect humans. For instance, mumps, once thought to exclusively infect humans and select primates, has been found in bats, highlighting the complexity of their transmission dynamics.
Furthermore, paramyxoviruses exhibit a wide range of outcomes when infecting different hosts, causing minor infections in some and deadly diseases in others. This variability adds to the mystery surrounding their pathogenicity and challenges the development of effective treatments and vaccines.
Within the paramyxovirus subfamily, rubulaviruses, which include mumps, are of particular concern. These viruses can easily infect humans, apes, pigs, and dogs, especially in close quarters. This ability to jump species boundaries raises the specter of potential pandemics fueled by rubulaviruses.
Measles, one of the most well-known paramyxovirus infections, has a history dating back to the 9th century. However, it wasn’t until 1757 that a Scottish physician identified the infectious agent responsible for the disease. While some experts believe that measles could eventually be eradicated, similar to smallpox, the emergence of new diseases like Nipah underscores the challenges in achieving this goal.
In a world interconnected by global travel and trade, viruses are increasingly jumping from animals to humans at alarming rates. A report published in 2022, titled “Strengthening Australia’s Pandemic Preparedness,” highlights the growing threat of viruses with pandemic potential. On average, two novel viruses appear in humans each year, and the proportion of these viruses capable of causing larger outbreaks is on the rise. Many of these emerging viruses, including paramyxoviruses, have the potential to spread across continents, presenting a formidable challenge to global health security.
The specter of the ‘Big One,’ driven by paramyxoviruses with the contagiousness of measles and the deadliness of Nipah, looms large in the realm of infectious diseases. While the world continues to grapple with the ongoing COVID-19 pandemic, it is imperative to remain vigilant and prepared for potential future pandemics. Understanding the complexities of paramyxoviruses, their ability to jump species barriers, and their varying pathogenicity is crucial for developing effective strategies to mitigate the risks they pose. The lessons learned from the past and the ongoing research into these enigmatic viruses will be instrumental in safeguarding humanity against the next pandemic.