Genetic diversity of porcine circovirus 3 strains and the first detection of two different PCV3 strains coinfecting the same host in Minas Gerais, Brazil.

Porcine circovirus 3 (PCV3) is a recently emerged circovirus discovered in 2016 that has drawn the attention of the swine industry worldwide. In this study, we evaluated the genetic diversity of PCV3 strains on pig farms. A total of 261 samples from sows, weaning pigs, growing pigs, and stillborn/mummified fetuses were analyzed by quantitative real-time PCR. The results revealed that at least two main lineages of PCV3 are circulating in Brazil. For the first time, it was possible to detect the presence of two different PCV3 strains in the same host.