Burke’s third criterion was “intrinsic evolvability,” meaning readiness to mutate and to recombine (or reassort), which “confers on a virus the potential to emerge into and to cause pandemics in human populations.” As examples he returned to retroviruses, orthomyxoviruses, and coronaviruses. “Some of these viruses,” he warned, citing coronaviruses in particular, “should be considered as serious threats to human health. These are viruses with high evolvability and proven ability to cause epidemics in animal populations.”
