Traditional methods to determine recombination events only interrogate on the viral population level. This method is limited in that it only allows one to determine the dominant recombinant strain and does not allow for the determination of recombination frequency nor the extent of recombination events. If that weren’t enough, traditional studies have been carried out in vitro rather than in a natural infection in a host animal. In the May issue of Journal of Virology, Zhang and colleagues utilized microfluidics to enrich for recombination events in a mouse host after co-infection with two mouse norovirus strains. They detected recombination events as rare as 1/300,000 between the virus strains at several locations in the virus genome. These results implicate recombination as a mechanism of genetic diversity in the infected host.