Emergence of a new recombinant coronavirus

Viruses like influenza, HIV, and coronaviruses routinely swap genetic material between strains. If the genetic material of the human SARS-CoV-2 were to be combined with the genetic material of an existing animal coronavirus — such as a virus endemic in fowl, swine, rodents, or even dogs and cats — it could create a hybrid that spawns a new pandemic, just as the occasional hybridization of human and bird influenza viruses is known to give rise to human influenza pandemics. When an animal cell happens to be co-infected with two different coronaviruses, recombination between two parental strands can occur, giving rise to a novel hybrid genome that just might be better at replication than its parents.

There is already evidence that SARS-CoV-2 strains are recombining with other SARS-CoV-2 strains. Fowl coronaviruses and swine coronaviruses are widespread problems in commercial animal husbandry, and mouse hepatitis virus has been a common nuisance infection in laboratory mouse colonies. SARS-CoV-2-infected individuals who have close contact with coronavirus-infected animals could easily serve as hosts for the generation of recombinant viruses.

Given the huge number of SARS-CoV-2 infected humans, the chances are good that someone somewhere on earth might be simultaneously infected with SARS-CoV-2 and an animal coronavirus — and some of their cells infected with both — giving rise to novel hybrid virus recombinants.