Genetic meltdown: A genomic crisis due to an extraordinarily high rate of mutation, a phenomenon known to occur in viruses and perhaps in other organisms.
For example, the antiviral agent Ribavirin acts by inducing genomic meltdown. The drug accelerates the already-high mutation rate of RNA viruses, creates a genomic crisis, and destroys the infectivity of the virus.
There is a limit to how much variation a genome can tolerate without irretrievably degrading its genetic information. If a population of viruses is replicating at the brink, just a bit of extra pressure from a mutagen, such as ribavirin, can nudge it into the abyss of genetic meltdown, resulting in an inability for it to replicate and survive.