They are the only mammals that have the ability to fly. They make you tall, fast and powerful. Immunity and longevity are added to its main characteristics. And killing them is prohibited because they play several important roles in environmental management: they devour tons of disease-carrying insects and are essential for the pollination of many fruits. However, these solitary, nocturnal and numerous creatures, are associated with ill and medical concerns.
Its ability to coexist with viruses that can be transmitted to other animals, particularly humans, could have consequences. For example, the pandemic caused by the coronavirus SARS-CoV-2 where everything indicates that these animals were the origin of the infection. In this sense, knowing the viruses present in these species represents a great unknown that, since the conicet, they are in charge of revealing. researchers from Laboratory of Human Virology of the Institute of Molecular and Cell Biology of Rosário published their results on the characterization of viromes present in five species of bats from Argentina. The scientists carried out the studies with samples of feces from bats that inhabit two urban geographic sites in the province of Santa Fé and were able to identify thirty-five new viruses with a DNA genome.
In dialogue with the UNQ science news agencythe researcher Elisa Bolatti he explains like this: “Our idea is to find out which viruses these bats have in order to take the necessary precautions if any of the viruses that can be detected are potentially pathogenic for humans or other animals.” And it emphasizes that the spirit of the investigation is conservationist because it seeks to emphasize “the importance of bats in the ecosystem and not stigmatizing them more”.
Bats play a key ecological role as pollinators and controllers of insect populations, but they also act as reservoirs for viruses, many of which can infect humans, such as SARS-CoV-2. According to Bolatti, this is because bats have developed an impressive immune system, which allows them to control these viral infections without getting sick, being able to carry and spread the viruses. Then, “by the human encroachment of wild frontiers, species that would naturally have no interaction came into contact”. It is then that a bat can come into contact with an intermediate host, such as domestic or breeding animals, and this is where zoonotic events occur.
How was this study prepared?
The Conicet researcher says that for the study it was chosen to sample populations of bats that inhabit two urban locations. One of them, with unique characteristics in South America, located in the center of the city of Rosário, in the attic of the building where the Faculty of Law operates. There lives a migratory colony of more than 30 thousand individuals that cover the ceilings and walls of the place. Are the females of the species Tadarida brasiliensis They go there to give birth and nurse their young until they reach a certain degree of autonomy and then leave.
The other sampling site is located in a town on the outskirts of Rosario, Zavalla; there is the Villarino park, where the Faculty of Agronomy and a Conicet Institute are located. Four species of bats inhabit the park’s trees and have a resident, non-migrating lifestyle. Bolatti explains that to collect the samples, large mist nets are placed between tree and tree and wait until dusk, then the net is lowered and the captured bats are placed in cotton bags to collect the feces. “Once they are released, no animals are harmed and we try to disturb them as little as possible,” he said. recounts.
DNA is extracted from bat feces, which are the molecules that will make it possible to identify the viruses that were present in the animal. Second, the nucleic acid samples were transferred to Slovenia to be analyzed with next generation sequencing (NGS) techniques. NGS “are ideal tools for virus discovery” because they allow the reading of millions of DNA fragments in a massive and parallel way. These sequences are then examined with bioinformatics programs that are able to reassemble the complete viral genomes present in the samples.
“Using this methodology, viral biodiversity has exploded in the last five years,” he says. Adriana Giri, director of the Human Virology Laboratory at IBR. It is interesting how the knowledge of this diversity led to a paradigm shift where “viruses are no longer considered only as pathogens, but also as actors in the ecological balance of a given microenvironment”, he says.
With this work, thirty-five new members are added to the vast universe of viral biodiversity that the researchers classify into six different families. “One of them has viruses that are pathogenic for humans, the parvoviruses”, says Bolatti, however, he clarifies: “we could not say that the viruses we found have zoonotic potential”.
And he concludes: “We are talking about biodiversity, ecology, interaction between different ecosystems. We must start to value and respect the other organisms that live with us on our planet, without them there is not much time left for human beings, we must be aware of that”.