The bat has been in the dock since the beginning of the Covid-19 pandemic. However, Israeli researchers believe there is not enough evidence to indict him. Conversely, the bat would exhibit a balanced immune response against viruses that have evolved over millions of years.
More than two years after the start of thefrom , we do not yet know for sure its origin. Among the animals involved, the they have a bad reputation, considered reservoirs of viral pathogens, including SARS-CoV-2.
Is the bat really an animal reservoir of viruses?
Aconducted by the Tel Aviv University researchers reveals many cases where, according to them, there is not enough evidence to accuse them . ” When considering the interaction of bats with the time seems ripe for a paradigm shift “, They write . First, they wondered if bats were really virus reservoirs. A reservoir animal is defined as a population in which the pathogen can be maintained permanently and from which infection is transmitted to the target population.
Although more than 100 bat-associated viruses have been identified as important for emerging and re-emerging human infections “, The researchers believe there is a lack of evidence to consider these animals as reservoirs. They found that in 48% of cases, the isolation of theof the virus it hadn’t even been done. Furthermore, the simple isolation of a virus would not be sufficient to consider an animal as a reservoir because there should also be an established route of transmission.
An effective immune system e small zoonotic danger for humans “
According to the study, bats have ahighly effective that allows them to better deal with a variety of deadly viruses than other mammals. It has been 60 million years since bats evolved to adapt to powered flight. Likewise, they deal with viruses that have evolved over millions of years and show a moderate response during inflammatory processes. They then recover and remain immune by developing a high level of antibodies. ” often without becoming a reservoir “, The authors write.
” After’, their risk of relapse, to the point of becoming contagious, is low. The spread of viral pathogens can only occur if bats harbor the same pathogenic virus for humans. However, many viruses carried by bats cannot infect humans without first undergoing a natural process of evolution, which means that bats carry the ancestral viruses and not the human pathogen. . “
It cannot be ruled out that bats may have been carriers of an ancestral virus which, at some point, could have mutated into a human pathogen. However, Israeli researchers conclude that, with the exception of some viruses, bats pose minimal dangerfor man.
Instead, they focus on showing that bats’ unique antiviral immunological capabilities need to be better studied to fight our own diseases. These animals also play an important role in the extermination ofthe replanting of deforested areas and the pollination of some crops.