The exposure of urban rodents to the human COVID-19 virus and the potential for viral recombination

All of us are affected by the COVID-19 pandemic, which is caused by a virus (technically, SARS-CoV-2) that originally jumped from an animal (probably a bat) into a person. Now the virus is spreading person-to-person directly. COVID-19 is a coronavirus, and coronaviruses are very common in wild animals. While each coronavirus typically infects one species of animal, coronaviruses can move between animal species too. So the general idea is that animals are "reservoirs" of viruses that sometimes moves into people. Because so many people are getting infected with COVID-19, we think that humans might now be a virus reservoir infecting animals. If this does happen, it's most likely where there are high densities of people and of animals - such as rodents in cities, where large numbers of people and rodents live cheek-by-jowl. This is the idea we want to test. But why does this matter? Different viruses can also mix their genetics (technically, recombine), and so we also wonder if the human COVID-19 does infect rodents, whether it will then recombine with other coronaviruses already in those rodents. There are a lots of 'ifs' in these last few sentences, which is because these are just theories that we have. We now want to see if these theories - these 'ifs' - are correct. To do this we want to catch city-dwelling rats and mice that we'll then screen for the human COVID-19 virus, or close relatives of it.