Infected, but healthy. The ability of bats to live with different types of viruses, including coronaviruses of which the Sars-CoV-2 responsible for the Covid-19 pandemic is part, was studied by a group of scientists from the State University of Milan in a work published in the ‘Journal of Royal Society Interface’. Researchers at the university’s Center for Complexity & Biosystems (CC&B) have thus discovered that “success in keeping viruses at bay derives from the variations in body temperature characteristic of bats”.
Bats include more than 1,400 species, representing about a quarter of all mammals – they explain from UniMi – and populate every type of habitat. Some bat species are capable of hibernating during the winter season, when the temperature drops, prey is scarce and food needs can easily exceed the available resources. During the day, most of these mammals decrease their activity and go into torpor to hunt at dawn, when the outside temperature is lower and the food is more abundant.
The CC&B scientists led by Caterina La Porta, professor of general pathology at the Department of Environmental Sciences and Policies of the University, and Stefano Zapperi, professor of theoretical physics at the Department of Physics, have shown that “the peculiar variations in the body temperature of bats are at the heart of their unconventional coexistence with viruses. ”
Using a minimal model of virus-host interaction and analyzing experimental data from the literature, the researchers were able to assess the contribution of daily numbness in maintaining chronic viral infections in bats.
“We have shown that daily numbness also contributes to a reduction in the immune response, preventing the risks associated with chronic inflammation,” says La Porta.
“Our model of the interaction between virus and immune response presents interesting mathematical features that show how a non-chaotic quasi-periodic attractor makes the system more robust against perturbations of the sleep / wake cycle”, concludes Zapperi.