recombination

It's not just the resurgence of ancient diseases, but the fact that pathogens can and will trade genetic information if they come into contact with one another, a process known as viral recombination.

Natural selection leaves subtle signatures on our genome, but these marks can erode over generations due to recombination, where segments of DNA are shuffled and diluted.

When this occurs, there is potential for a “recombination” of the genetic code from both viral strains.

This reshuffling, due to random segregation of chromosomes and meiotic recombination, is important in generating novel and beneficial genetic configurations in natural populations and during breeding.

One discovery is particularly interesting with regard to the emergence of new viruses: In host animals that are simultaneously infected with different viruses, a recombination of viral genes can occur during virus replication.