Evaluating the BioCascade – Viable Virus Aerosol Sampler’s Size-Separation Efficiency and Ability to Maintain Virus Viability

MD. TANVIR AHMED, Kamaljeet Kaur, Kerry Kelly, University of Utah

     Abstract Number: 217
     Working Group: Bioaerosols

Abstract
Effectively capturing and preserving airborne viruses is essential for early detection, outbreak prevention, and improving public health responses to respiratory infections. However, current air sampling methods often struggle to efficiently retain virus viability in collected bioaerosols. The BioCascade - Viable Virus Aerosol Sampler (BC-VIVAS) system is designed to collect viable bioaerosols in four aerodynamic diameter bins: >10 µm, 4–10 µm, 1.5–4 µm, and <1.5 µm. This study evaluates this system's size-selective separation efficiency using monodisperse fluorescent polystyrene latex spheres (PSLs). It also assesses the ability of this system to maintain MS2 bacteriophage viability as well as the minimum airborne virus concentration needed for the bacteriophage to lyse E. coli cells. Size-selectivity testing demonstrated effective separation of fluorescent PSLs into three aerodynamic diameter bins. However, PSLs >10 µm in diameter were not efficiently collected, likely due to losses during atomization or dryer. Viability testing confirmed that MS2 bacteriophages were successfully detected at airborne concentrations as low as approximately 820 pfu/m3 following atomization and drying. These findings highlight the BC-VIVAS system’s potential for size-selective, viability-preserving air sampling in support of epidemiological monitoring and infection control.