US research shows no influence of AH1N1 on PCV2 replication

In a study by several scientists from Purdue University, the AH1N1 virus did not influence Porcine Circovirus type 2 (PCV2) replication in dually infected pigs.

The researchers from the Indiana-based university's Department of Comparative Pathobiology said that PCV2 and AH1N1 are important pathogens for Porcine Respiratory Disease Complex (PRDC), which is economically significant worldwide.

They said, "The pathogenesis of PCV2-SIV coinfection is unknown. In this study, we focused on establishing a challenge model for PCV2 to determine whether AH1N1 influences PCV2 replication and increases the severity of PCV2-associated disease."

Caesarean-derived colostrum-deprived pigs were inoculated intratracheally with cell culture medium only (negative control group), PCV2 only, or PCV2 followed one week later with AH1N1. Two pigs from each group were necropsied at 12, 21, 28, and 35 days after inoculation.

Coinfection with SIV did not increase the number of PCV2 genomic copies in serum or target tissues or the severity of microscopic lesions associated with PCV2 in lung or lymph node.

The antibody titre to PCV2 did not differ significantly between PCV2-AH1N1- and PCV2-infected groups.