INFLUENZA A VIRUS (IAV) SURVEILLANCE USING PRE-WEANING ORAL FLUID SAMPLES

摘要

Influenza A Virus (IAV) is a major respiratory pathogen in contemporary production systems. IAV circulates endemically in all age groups, including suckling pigs. That is, IAV transmission and infection occurs in piglets despite the presence of maternally-derived antibodies. The feasibility of conducting IAV surveillance using pre-weaning oral fluid samples from litters of piglets was evaluated in four -12,500 sow, lAV-vaccinated, breeding herds. Oral fluid samples were collected from 600 litters 24hours prior to weaning. Serum samples from their dams were included for comparison. Litter oral fluid samples were tested for IAV by virus isolation, quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR), RT-PCR subtyping, and sequencing. Commercial nucleoprotein (NP) enzyme-linked immunosorbent assay (ELISA) kits and NP isotype specific assays (lgM, IgA, and IgG) were used to characterize NP antibody in litter oral fluid and sow serum.