In a race to prevent future deadly pandemics, scientists are trying to pinpoint the animals and regions where the next Ebola or Zika might arise — before the viruses start harming people. But some experts argue that it makes more sense to look for new viruses in humans, not other animals. In fact, the next emerging infectious disease is probably already out there, making people sick.
“Right now, we’re always on defense.”
Animals host a massive number of viruses, and sometimes these viruses make the jump to humans. (These viruses are called zoonoses.) This happens pretty rarely, but when it does, it can wreak havoc: most pandemics in recent memory like HIV, pandemic influenza, and Zika were caused by viruses that started out in animals. The Ebola virus, which probably jumped from bats, killed more than 11,000 people during the recent outbreak in West Africa.
If there were a way to predict which infectious disease might emerge and threaten humans next, maybe it could give us a head start on a vaccine, or prevention strategy. But the challenge is even more complicated than you’d think, because where exactly do you go looking for the next pandemic? In animals, which carry a vast array of viruses that might never infect people? Or in humans, once a virus has made that rare leap — but before it spreads out of control?
Peter Daszak, an epidemiologist with the research and conservation nonprofit EcoHealth Alliance, wants to find these viruses before they make anyone sick. “If we allow these viruses to get into people, it’s already too late,” he says.