Rodents such as rats, mice, and voles can also contain viruses that can sometimes cross over to our species.
Researchers have discovered a widespread and prevalent coronavirus in Sweden's red-backed bank voles (Myodes glareolus), which they have named the Grimsö virus after the site of its discovery.
"We still do not know what potential threats the Grimsö virus may pose to public health. However, based on our observations and previous coronaviruses identified among bank voles, there is good reason to continue monitoring the coronavirus amongst wild rodents," virologist Åke Lundkvist from Uppsala University in Sweden said.
Bank voles are among the most widespread rodents in Europe. Their pathways frequently cross with those of our own species, and they are recognized hosts of the Puumala virus, which causes nephropathia epidemica in humans.
Voles have been known to seek shelter in human structures when fleeing bad weather, which increases the chance of us catching a sickness they bring into our homes.
Even before the COVID-19 pandemic, Lundkvist and his colleagues were trying to track wildlife sickness in voles in order to predict when their viruses would spread. Given the persistent speed of climate change and habitat destruction, human contacts with voles are likely to become more frequent in the future.
Between 2015 and 2017, researchers at Uppsala University analyzed 450 wild bank voles from Grimsö, a region west of Stockholm. When the team tested the critters for coronaviruses, they discovered a new betacoronavirus prevalent in 3.4% of the sample.
Betacoronaviruses are typically found in bats and rodents, and when they infect humans, they cause common colds and respiratory viruses such as SARS-CoV-2.
The new vole virus has not yet been detected in humans, but if COVID-19 has taught us anything, it is that we need to strengthen our surveillance of wildlife disease to prevent future outbreaks.
Researchers in Sweden discovered seven different Grimsö virus strains circulating in bank vole populations over the period of three years.
Furthermore, other closely related coronaviruses were widely disseminated among voles in various countries of Europe, such as France, Germany, and Poland, suggesting that these animals are natural disease reservoirs.
The Grimsö virus's high divergence is a red flag. This suggests that the virus is adaptable to new hosts and environments.
The diverse strains in circulation may have originated in bank voles or crossed across from another species.
The study was published in Viruses.
