Abstract View
Environmental Effects on Betacoronavirus Resuspension and Transport at High Risk Facilities
Sunil Kumar, Tatiana Baig, MARIA KING, Texas A&M University
Abstract Number: 151
Working Group: The Role of Aerosol Science in the Understanding of the Spread and Control of COVID-19 and Other Infectious Diseases
Abstract
To objective of this study is to understand the effect of the environment on the transmission, deposition and spread of virus aerosols in the ventilation airflow and enable early detection of virus particles in room size spaces. In an air-conditioned model hospital chamber bovine betacoronavirus (BCoV) aerosols as SARS-CoV-2 simulants were disseminated to test the effect of different environmental conditions including temperature, relative humidity and air velocity on the stability and movement of the virus. Particle tracking velocimetry was used to monitor the size distribution, deposition and resuspension of the BCoV virus particles aerosolized at different temperature, humidity and air velocity values. At regular time intervals after aerosolization, the viruses were collected from the surfaces and quantified using quantitative reverse transcription polymerase chain reaction (RT-qPCR).
Two portable VBAC collectors at 100 L/min flow rate were used to sample the simulant virus particles from the air at two locations (patient’s bed and exhaust) in the chamber. The collected BCoV viruses were enumerated for viable and total counts. The aerosol collection results were used to gain information about the temporal and spatial concentration of the airborne viruses and whether they maintain their viability during aerosolization and transport. Based on the chamber mechanical blueprint, ANSYS Fluent computational flow model was created to simulate the entrainment of virus aerosols from a patient’s breath in the ventilation airflow and validated by the virus aerosol collections at the different locations. The experimental data, in good agreement with the simulation showed the entrainment of the virus in powerful vortices before impacting on surfaces or exiting through the air outlet. Mitigation efforts to change the airflow pattern significantly reduced the virus concentration in the patient’s breathing zone.