Detection of porcine reproductive and respiratory syndrome virus type 2 in air emissions from grow‐finish barns

Abstract Background Diagnosis of porcine reproductive and respiratory syndrome virus (PRRSV) infections can be accomplished using various sample types and testing methods. The objective of this study was to evaluate the feasibility of using air emission samples to detect the onset of PRRSV type 2 infections in growing pigs. Methods Air emissions and oral fluid samples were collected from three grow‐finish barns, stocked with PRRSV‐negative pigs every 2 weeks for 14–20 weeks. All samples were assayed for PRRSV using RT‐PCR. Results In all barns, PRRSV was initially detected in both air emissions and oral fluid samples at the same sampling event. Compared with oral fluids, air emissions collected subsequently yielded higher cycle threshold values and showed a lower likelihood of being RT‐PCR positive. Limitation Sampling was limited to three grow‐finish barns. Conclusion Air emission samples from pig barns are a biosecure and non‐invasive sample type that is comparable to oral fluids for detection of the onset of PRRSV infection.