Scientists have warned that forecasting the next pandemic will be “more difficult than we think.” The deaths are far from the only consequences of the pandemic, with healthcare systems, economies, and people’s mental health all suffering.
Because most viruses that cause human disease come from other animals, some researchers are attempting ‘zoonotic risk prediction’ to predict the next virus to hit us. However, experts argue in a new paper that these zoonotic risk predictions are limited and will not tell us which virus will cause the next pandemic.
Because most viruses that cause human disease come from other animals, some researchers are attempting “zoonotic risk prediction” to predict the next virus to hit us. However, in an Essay published in the open access journal PLOS Biology, led by Dr Michelle Wille at the University of Sydney, Australia, with co-authors Jemma Geoghegan and Edward Holmes, it is proposed that these zoonotic risk predictions are of limited utility and will not tell us which virus will cause the next pandemic. Instead, we should concentrate our viral surveillance efforts at the human-animal interface.
The observation that most of the viruses that cause human diseases come from other animals has led some researchers to attempt ‘zoonotic risk prediction’ to second-guess the next virus to hit us.
So-called zoonotic viruses have caused epidemics and pandemics in humans for centuries. This is exactly what is occurring today with the COVID-19 pandemic: the novel coronavirus responsible for this disease – SARS-CoV-2 – emerged from an animal species, although exactly which species is uncertain.
While many people want to get back to their old lives, the World Health Organization (WHO) has warned that the coronavirus pandemic is “not necessarily the big one.” In the United Kingdom, the Labour Party is urging the government to conduct annual planning exercises to prepare for an “era of pandemics.” While some scientists have attempted to predict how another infection might “jump” from animals to humans, a team from the University of Sydney has deemed these predictions “limited in value.”
As a result, one critical question is whether we can predict which animal or virus group will most likely cause the next pandemic. This has prompted researchers to attempt “zoonotic risk prediction,” which involves determining which virus families and host groups are most likely to carry potential zoonotic and/or pandemic viruses.
The SARS-CoV-2 virus was not the only one that spread from animals to humans. Zoonotic viruses have long been a part of human history; the plague is a zoonotic disease spread by fleas from rodents to other animals. Another example is rabies, which is spread when an infected animal (most commonly a bat) bites or scratches another.
As humans encroach more on animal habitats, zoonotic diseases have more opportunities to cross the species barrier. Scientists recognize that discovering and understanding them is more important than ever in order to prepare for future pandemics.
Dr. Wille and her colleagues identify several major issues with attempts to predict zoonotic risk. For starters, they are based on small data sets. Despite decades of research, we have likely identified less than 0.001% of all viruses, even from the mammalian species from which the next pandemic virus will most likely emerge.
Second, these data are heavily skewed toward viruses that most commonly infect humans or agricultural animals, or are already known to be zoonotic. Most animals have not been surveyed for viruses, and viruses evolve so quickly that any such surveys will be out of date and thus of limited value.
Instead, the authors argue that a new approach is required, one that includes an extensive sampling of animals and humans at the points where they interact – the animal-human interface. This will allow for the detection of novel viruses as soon as they appear in humans and before they cause pandemics. Such enhanced surveillance may aid in preventing something like COVID-19 from occurring in the future.
According to Sydney scientists, most animals have not been screened for viruses. Because of the infections’ rapid mutation rates, any screenings would quickly become out of date, they added. As a result, the scientists are advocating for a new approach in which “extensive sampling” of both animals and humans is conducted in areas where they commonly interact, dubbed “the animal-human interface.”