New bat species are close relatives of the one that carries COVID-19

April 22 (UPI) -- Scientists have named four new species of African leaf-nosed bats, close relatives of horseshoe bats, the bat group that hosts the virus that causes COVID-19.

Horseshoe bats and fruit bats serve as reservoirs for thousands of viruses, including coronaviruses, but like the viruses they harbor, these bats are poorly understood.

"With COVID-19, we have a virus that's running amok in the human population. It originated in a horseshoe bat in China," Bruce Patterson, curator of mammals at the Field Museum in Chicago, said in a news release. "There are 25 or 30 species of horseshoe bats in China, and no one can determine which one was involved. We owe it to ourselves to learn more about them and their relatives."

Patterson is the lead author of a new study describing the four new African leaf-nosed bat species, published Wednesday in the journal ZooKeys.

Bats are diverse, abundant and difficult to study. There are at least 1,400 documented species of bats, but more than a quarter of them were discovered in just the last 15 years. Scientists are certain dozens more, perhaps hundreds, remain undiscovered.

As the coronavirus pandemic has made clear, the dearth of science on bats is dangerous.

"None of these leaf-nosed bats carry a disease that's problematic today, but we don't know that that's always going to be the case. And we don't even know the number of species that exist," said study co-author Terry Demos, post-doctoral researcher in Patterson's lab at the Field Museum.

The four new species belong to the family Hipposideridae. They're named for the bow-like skin flaps on their nose that help the bats focus their calls, enhance their echolocation abilities and quickly hone in on elusive prey. Relatives of the new species are found throughout Africa, Asia and Australasia, but less is known about Hipposideridae family members residing in Africa.

Scientists discovered the new species -- none of which have scientific names yet -- after conducting a genetic analysis of African leaf-nosed bat specimens sourced from various museum collections. Though the newly discovered species look similar to their closest relatives, their DNA revealed distinct evolutionary histories.

Viruses are everywhere. There are millions of viruses, found in everything from rodents to flowers. Most are unknown. Most are also likely harmless, unable to infect humans or both. But those that do find a way to make the jump to humans often originate in bats.

Scientists suspect COVID-19 evolved in horseshoe bats in China and then made the jump to another mammal, possibly scale-covered pangolins, before infecting humans. The social nature of a bat colony makes them ripe for fast-spreading, fast-evolving viruses.

"Because they huddle together and take care of each other, it doesn't take long for a pathogen to get passed from one end of the colony to the other," Patterson said.

Bats are feature a unique physiology that allows them to host large numbers of viruses without ever getting sick.

"Flying is the most energetically expensive way to get around," Patterson said. "If you skin a bat, it looks like Mighty Mouse, they have hardly any guts, they're all shoulders and chest muscle. They're incredible athletes."

To help them handle the difficult task of spending life in the skies, bats have evolved fast metabolisms and strong immune systems. The flying mammals are able to quickly repair damaged DNA.

Despite their near-omnipresence, bats rarely closely interact with humans, but as human development continues to break down the barriers between people and wildlife, the chance of a virus making the leap from bats and other mammals to humans increases. By studying new bats, their behaviors and the variety of viruses they host, humans can better prepare for the next pandemic.

"Leaf-nosed bats carry coronaviruses -- not the strain that's affecting humans right now, but this is certainly not the last time a virus will be transmitted from a wild mammal to humans," said Demos. "If we have better knowledge of what these bats are, we'll be better prepared if that happens."