Reconciling individual and population levels of porcine reproductive and respiratory syndrome virus evolution
- 55 Downloads
Porcine reproductive and respiratory syndrome virus (PRRSV), a member of the family Arteriviridae, represents one of the most challenging pathogens in the swine industry, with serious economic impact. Unfortunately, despite widespread application, vaccination has not been successful in effectively controlling the virus, mainly because of the limited cross-protection among different strains (Kimman et al., 2009).
A longitudinal study revealed a gradual rise in genetic divergence among field isolates of PRRSV type 2 (Brar et al., 2015). Similar to other RNA viruses, PRRSV displays high mutation and recombination rates, which give rise to a plethora of new variants able to rapidly explore the fitness landscape. The substantial viral population size at the host and the population level should create optimal conditions for natural selection to act. Accordingly, different studies have pointed out selective pressures, mainly related to host immunity, which affect PRRSV evolution...