Understanding the Size and Prevalence of Respiratory Viruses in Hospital Settings
KERRY KELLY, Md. Tanvir Ahmed, Kamaljeet Kaur, Elizabeth Myers, Darrah Sleeth, Selah Willis, Chase Crimmins, Kristi Warren, University of Utah
Abstract Number: 44
Working Group: Bioaerosols
Abstract
Respiratory viruses, such as severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus, and seasonal influenza, are responsible for substantial cases of severe illnesses and death. For example, seasonal influenza epidemics result in approximately 3 to 5 million cases of severe illness and 290,000 to 650,000 respiratory deaths annually. Front-line workers can be particularly at risk for respiratory viruses; however, determining the size and viability of bioaerosols containing respiratory viruses remains a challenge. Although collecting airborne-virus genetic material is relatively straightforward, determining whether a bioaerosol contains viable virus is much more challenging because viruses can become inactive during sampling. In this study we use a novel instrumentation, the biocasade-viable virus aerosol sampler (BC-VIVAS), to understand the frequency, the size, and the viability of three respiratory viruses (influenza A, influenza B, and SARS-CoV2) in hospital settings. The BC is a 3-stage planar cascade impactor that gently collects airborne particles through impaction into a liquid medium. It separates aerosol samples into three size fractions, > 10 μm, 4 - 10 μm, and 1.5 - 4 μm. The VIVAS collects aerosols using laminar-flow water condensation to enlarge and collect aerosols smaller than 1.5 μm in diameter (when integrated with the BC), which are then captured in a liquid medium. We collected aerosol samples during the winter influenza/SARS-CoV2 season of 2024/2025 in four locations: 1) the dental school patient bay (with 40 patient chairs and numerous aerosol-generating procedures), 2) the medical intensive care unit, 3) the pulmonary unit, and 4) the waiting room of the emergency department. The preliminary results show that approximately 10% of the samples from the pulmonary unit and emergency department contained genetic material for SARS-CoV2 or influenza A or B. All of the genetic material occurred in the same size bin. The samples are currently being analyzed for cytopathic effects, and we anticipate discussing the viability results during this presentation.