How to see the next viral threat coming
The rapid spread of the novel coronavirus has followed an eerily familiar pattern. First recognized just weeks ago in the city of Wuhan, China, the virus is suspected of having originated in animals and later began infecting humans, most likely through contact with an infected animal in a food market. By the time the world began to understand its threat, the virus had already reached multiple countries and hopped an ocean. It is now infecting tens of thousands of people and has caused more than 400 deaths.
In their efforts to contain the virus, public health officials have taken swift and comprehensive action, including quarantining people who may have been exposed to the virus and restricting travel to and from affected areas. Yet even these measures may not stop the virus’ spread entirely.
Respiratory viruses spread rapidly, and they’re frustratingly good at it. In recent years, outbreaks caused by other such viruses — including hand, foot and mouth disease viruses, Middle East Respiratory Syndrome coronavirus and the pandemic H1N1 influenza A virus — have together infected millions of people in many areas of the world. Public health interventions have helped to reduce viral activity over time without fully containing the viruses.
This is not to say that containment isn’t essential. It is, but it should be our last line of defense. What we need to better understand and respond to threats like the new coronavirus is a stronger early warning system — something that would give us time to put effective containment efforts in place before a virus has already gotten out of control.
Such an early warning system is possible by monitoring animals that harbor the viruses most likely to become threats to humans.
While it’s hard to predict when a virus will make the jump from infecting animals to humans, we do have a pretty good idea where that evolutionary leap will occur: Large farms, live animal markets and other places where humans come into contact with dense populations of animals are the most likely launching points for novel pathogens that spread from animals to people, so-called zoonotic diseases. Understanding what kinds of new viruses are circulating in these environments is a critical tool for predicting — and ultimately preventing — the next pandemic.
In my research program, we are bringing together researchers in human health, veterinary health and environmental health to learn what happens at this human-animal interface. Our team is working on farms and in animal markets in multiple countries to detect and study viruses that pass among animals and sometimes sicken livestock workers and handlers. (To see an example of our work, watch this video of a recent project in Vietnam).
This emerging collaborative field, often called “one health,” integrates knowledge from several different spheres, including human health, animal health, environmental health and agricultural businesses. The approach is gaining traction among academics, government officials and international policymakers as the best way to approach complex problems such as emerging zoonotic diseases. But we need to do more to integrate this approach into how we prepare for viruses like the newly emerged coronavirus.
For example, when researchers reach out to agricultural businesses about monitoring viral activity among farm animals, they are sometimes met with suspicion and mistrust. Yet the same biotech tools we are using to study novel viruses can also be used to advance agricultural production and to keep farmworkers and their communities healthy.
So as we continue the fight to control this coronavirus, we should also be preparing for the next viral crisis. Encouraging greater cooperation among those who study human health, animal health and environmental health would go a long way toward giving us that early warning system we so badly need to stay ahead of the next pandemic threat.
Gregory C. Gray is a professor of medicine, global health and environmental health at Duke University, where he leads the Duke One Health Research and Training Network, which conducts research and training in 14 countries.