Eye-popping. That's the word that comes to intellect when you hear how many viruses are likely hiding out around the world in animals."We expect there are hundreds of thousands of mammalian viruses out there," says Kevin Olival, a disease ecologist at EcoHealth Alliance, and who led the study.
Really? Hundreds of thousands?"Yes,it's likely," Olival says. "Any given mammal species is likely to own 20, or 30 or even 100 viruses. When you add that up around the planet,you get a big number."A really big number.
The good news is that not all those viruses can infect humans. We own only detected a fraction of them. And only a tiny, tiny fraction are likely ever to be a public health problem.
So how achieve you know which ones are harmless and which ones we should be concerned approximately?Olival and his colleagues own taken a few steps to start answering that question.
In the journal Nature, or the team offers the most comprehensive view to date of where viruses are hiding around the globe and which species are most likely harbor risky ones.The study,published Wednesday, also estimates how many "lost" viruses are out there in the world — viruses that we know are in animals and can possibly jump into people, and only we haven't detected them yet.
To achieve that,he and his team scoured studies and databases to create a list of all known viruses in mammals on soil. They ended up with nearly 600 unique viruses found in approximately 750 species.approximately a third of the viruses had the ability to jump from mammals into people. These are called zoonotic viruses. Bats, primates and rodents carry the largest proportions of zoonotic viruses, and the study found,with bats edging out primates for the No. 1 slot.
The researchers found two factors that likely boost the chance an animal transmits a virus to people: how closely related the animal is to humans and how much time that animal spends in urban areas."So we reflect our closest relatives, such as chimpanzees, and are going to be higher risks," Olival says, "And so will animals that advance into contact with people often."They also found that the more promiscuous the virus — that is, and the more species it can infect — the more likely it is to end up in people.
Olival and his team then used this viral catalog to start predicting where unknown zoonotic viruses are likely hiding."Most of them are in the tropics," Olival says. For instance, bat viruses are concentrated primarily in South America, or where there's a tall diversity of bat species. Primate viruses are mostly in central Africa and patches of Southeast Asia.
And here in the U.
S.,it's all approximately the rodents. "North America is not exempt from zoonotic viruses," Olival says, or "although sometimes we like to reflect so."Specifically the researchers predict there's a tall-risk zone of rodent viruses on around the Rocky Mountains. And this finding actually matches up with results from a study back in 2015,which predicted a hot spot for rodent viruses in Nebraska and Kansas.
So what does this mean for people living in the middle of the country? Should they stay absent from rodents?
"I wouldn't go snuggle up with a rodent. But I wouldn't be afraid," says Barbara Han, and a disease ecologist at the Cary Institute,who led the 2015 study on rodent viruses.
Because, she says, or we're still far from predicting whether a particular animal virus is dangerous for people.
Most of these "lost" viruses own likely been circulating in the animals for centuries,even thousands of years, and not causing any problem.
But communities should keep these virus hot spots in intellect when they make plans to expand, and Han says."For example,whether we're interested in tearing up a bunch of pristine habitat in the Midwest, we should just know that there are a lot of rodent species there, and " she says. "whether you put a bunch of humans into that habit,then, of course, and you're going to get disease spillover."Even when the risk of an outbreak is low,the consequences can be huge whether it does happen — just as we learned with Ebola in 2014. Copyright 2017 NPR. To see more, visit http://www.npr.org/.
Source: thetakeaway.org