Evaluation of the Aerosolized Transmission of Porcine Reproductive and Respiratory Syndrome (PRRS) Virus

Authors

Logan Hafer, University of Nebraska - LincolnFollow
Benny Mote Ph.D., University of Nebraska - LincolnFollow
Hiep Vu Ph.D., University of Nebraska - LincolnFollow
Amy Schmidt Ph.D., P.E., University of Nebraska - LincolnFollow

First Advisor

Amy Millmier Schmidt, Ph.D.; P.E.

Second Advisor

Benny Mote, Ph.D.

Third Advisor

Hiep Vu, Ph.D.

Committee Members

Amy Millmier Schmidt, Ph.D.; P.E.; Benny Mote, Ph.D.; Hiep Vu, Ph.D.

Date of this Version

3-31-2025

Document Type

Thesis

Citation

Hafer, L., Mote, B., Vu, H., and Schmidt, A. (2025). Evaluation of the Aerosolized Transmission of Porcine Reproductive and Respiratory Syndrome (PRRS) Virus. Undergraduate Honors Thesis. University of Nebraska-Lincoln.

Comments

Copyright Logan Hafer, Benny Mote, Hiep Vu, and Amy Schimidt 2025.

Abstract

Porcine reproductive and respiratory syndrome (PRRS) is a viral disease that has had a tremendous economic impact on the US pork industry. This study sought to isolate the PRRS virus (PRRSV) from air sampled within and downwind of PRRSV-positive swine farms to evaluate potential farm-to-farm aerosolized transmission risks. A simple and inexpensive air sampling unit was constructed and validated to collect samples for RT-qPCR testing. Testing at two locations in fall 2023 provided positive results from surface swabs and air samples obtained inside swine housing units and outdoors at up to 20 feet downwind of building exhaust fans. In 2024, three sampling events were conducted at naturally and mechanically ventilated swine barns with PRRSV-positive pigs using air samplers distributed downwind of buildings at distances up to one mile and immediately downwind of a field receiving irrigated effluent from an anaerobic lagoon associated with PRRSV-positive pigs. No downwind air samples from the 2024 sampling events tested positive for PRRSV. However, oral fluid samples collected from pigs housed in the mechanically ventilated facility were PRRSV-positive. Future sampling downwind of swine housing units will need to consider sampling duration, ambient weather conditions, and status of infection/viral load among housed pigs. By quantifying viral loads of air samples distributed longitudinally and laterally in the exhaust plumes downwind of PRRSV-positive swine farms, modelling of airborne viral dispersion using the model FLEXPART is anticipated. Expanding knowledge of PRRSV dispersion will promote additional preventative measures to limit its transmission and impact.