What is special about bat viruses? What we don't know could hurt us

Bats were once of particular interest to specialists and committed conservationists. But the global pandemic has put animals straight into the spotlight as the obvious original source of the novel coronavirus. Now, arcane research into the large numbers of viruses that live in bats has taken on a new urgency, along with discussions about what to do about the likelihood of disease in animals spreading to humans.

In Science magazine on Thursday, two bat researchers asked their colleagues to take a closer look at what we know for sure about bats and viruses, and suggested how we can find out more and how that knowledge could help us.

Daniel G. Streicker, a vampire bat researcher at the University of Glasgow, and Amy T. Gilbert, a disease ecologist at the National Wildlife Research Center in Fort Collins, Colorado, point to a number of knowledge gaps and lack of knowledge hard numbers to put some in common To prove perceptions.

Dr. Streicker said in an interview that we may have outdone ourselves in the focus of research. "I think we often try to explain why bats are special before we figure out how special is," he said.

First and foremost, the researchers write the “global health problem” of whether bat viruses are more likely to cause outbreaks than viruses harbored by other creatures.

The popular belief that bats contain more viruses than other animals does not hold up, they write when you look at the large number of bat species.

Bats are also not immune to the effects of all viruses. There is no question that many bats can live with viruses that can prove fatal to humans and other animals such as SARS and MERS.

The "key question," said Dr. Streicker, is whether bat tolerance to viruses causes the development of pathogens that are more dangerous to humans. Science still has no answer.

"We seem to lack really strong and convincing evidence that bat viruses are more diverse, more susceptible to infecting humans, or more dangerous when infecting humans than are viruses in other animals," he said.

It is not only necessary to understand the internal workings of bats. How bad spillover disease is and how it spreads depends on how people interact with bats, what type of bats are affected, where they live, and how they spread viruses among themselves.

"We need interactions between immunologists, virologists, ecologists and evolutionary biologists." That's starting to happen, he says, in part because of the pandemic.

Before the pandemic began, bat scientists urged such interdisciplinary work. For example, last week the National Science Foundation made a $ 1.67 million grant to the American Museum of Natural History, Texas Tech University, and Stony Brook University to help create the Global Union of Bat Diversity Networks.

Tigga Kingston, an ecologist at Texas Tech, had met with her colleagues at the museum and in Stony Brook at bat research meetings for half a dozen years and discussed the need for further connections. There were many networks of bat researchers, some regional, some dedicated to a specific topic, but no global network to promote communication between all bat researchers.

In 2019, she said, they decided to move from planning to action just as the National Science Foundation was trying to promote more of the kind of "metanetwork" they were pondering. The fit was ideal.

Then, of course, the pandemic emerged and basic research and conservation efforts took on a new urgency. Suddenly she said, "Everything we do has relevance to Covid-19", from metabolic studies to evolution to conservation issues.

"We need immunologists who work alongside genomists who work with ecologists who work with people who study the animal's physiology," she said. Until that happens, she added, "We really have no hope of mitigating this." Types of events. "

In the science article, Dr. Streicker and Dr. Gilbert also pointed to certain areas of research where bats could serve as test populations for new disease control techniques, such as vaccines for animal populations.

Rabies in animals such as foxes has been successfully combated with vaccines against baits that foxes eat. That wouldn't work on bats, but according to Dr. Streicker could apply a vaccine to bat fur and spread it through contact.

In the future, genetic engineering techniques like Crispr could even be used to genetically manipulate bats to make them resistant to some viruses. This has been tested with mosquitoes and discussed for use in mice and Lyme disease. "I think that is very far in the future," said Dr. Streicker, "and there are all kinds of ethical questions."

But there are other ways to make a substantially contagious vaccine, possibly by binding proteins that promote an immune response to a virus that is infectious but not harmful in bats. For you or us.