SARS-CoV-2 Detection in Air Samples from Inside Heating, Ventilation, and Air Conditioning (HVAC) Systems-COVID Surveillance in Student Dorms

SINAN SOUSAN, Ming Fan, Kathryn Outlaw, Sydney Williams, Rachel Roper, East Carolina University

     Abstract Number: 34
     Working Group: Aerosol Science of Infectious Diseases: What We Have Learned and Still Need to Know about Transmission, Prevention, and the One Health Concept

Abstract
Detection of SARS-CoV-2 is important for the control of COVID-19. Early detection of SARS-CoV-2 in an area can trigger protective measures, including masking, testing individuals for infection, isolation of those infected, and quarantine of exposed individuals. Wastewater testing has been employed, but sampling is difficult, and extensive processing is needed. We pursued research to detect SARS-CoV-2 in air samples. We sampled air inside HVAC ducts in two large student dormitories and a COVID isolation suite containing student(s) who had tested positive for COVID-19. We assessed four methods to collect air samples: Filter Cassettes, Button Sampler, BioSampler, and AerosolSense sampler. We designed protocols to preserve the RNA in sample collection and processing for direct PCR analysis. Results from air sampling were compared to random testing of students in the dorms. For the two large dorms with a normal student population, we detected SARS-CoV-2 in 11 samples over a 3 month period. When compared with student nasal swab qRT-PCR testing, we detected SARS-CoV-2 in air samples when a PCR positive COVID-19 student was living on the same floor of the sampling location with a detection rate of 75%. For the isolation dorm, we had a 100% SARS-CoV-2 detection rate with the AerosolSense sampler. Our data suggest air sampling may be an important SARS-CoV-2 surveillance technique in office buildings and especially for buildings with congregant living settings (e.g., dorms, correctional facilities, barracks). Future building designs and public health policies should consider the implementation of HVAC surveillance for multiple respiratory pathogens.