Abstract
Introduction
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), has spread globally. The major reservoir for SARS-CoV-2 transmission remains controversial, with the airborne route remaining a possible transmission vehicle for carrying the virus within indoor environments. This study aimed to detect contamination of SARS-CoV-2 in high-efficiency particulate air (HEPA) filters within hospital isolation rooms of confirmed COVID-19 patients, exploring the role of nano-treatment of these filters with silver and titanium dioxide nanoparticles (Ag/TiO2 NPs).
Materials and methods
We investigated the effectiveness of Ag-NPs/TiO2-treated HEPA filters in the air of rooms occupied by patients with confirmed COVID-19 in a university teaching hospital in the Eastern province of Saudi Arabia during the first wave of the pandemic. Ag/TiO2 NPs were designed and coated on HEPA filters to examine the filtration efficiency and antiviral ability in the presence of aerosolized virus particles. A total of 20 viral swab samples were collected from five patients’ rooms before and after treatment with nanoparticle-prepared solutions into the sterile virus-transporting media. Samples were evaluated for SARS-CoV-2 with a reverse transcription-polymerase chain reaction.
Results
Two samples taken from the HEPA filter air exhaust outlets prior to nano-treatment tested positive for SARS-CoV-2 RNA in the intensive care unit, which has stringent aerosolization control procedures, suggesting that small virus-laden droplets may be displaced by airflow. All air samples collected from the HEPA filters from the rooms of patients with confirmed COVID-19 following nano-treatment were negative.
Conclusion
We recommend further experimental exploration using a larger number of HEPA filters in areas with aerosol-generating procedures, along with viability studies on the HEPA filters to facilitate decision-making in high-risk facilities regarding the replacement, storage, and disposal of HEPA filters in wards occupied by cases diagnosed with a highly transmissible disease.
【저자키워드】 SARS-CoV-2, airborne, outbreak, Silver-titanium nanoparticles, 【초록키워드】 COVID-19, Treatment, coronavirus disease, coronavirus, pandemic, intensive care, Antiviral, hospital, media, Transmission, droplet, virus, Saudi Arabia, HEPA filter, Spread, SARS-CoV-2 transmission, Contamination, viability, Patient, Effectiveness, SARS-CoV-2 RNA, disease, First wave, COVID-19 patients, Efficiency, aerosol-generating procedures, acute respiratory syndrome, virus particles, material, HEPA, positive, filtration, Isolation room, FIVE, swab sample, Result, tested, detect, collected, Sample, investigated, diagnosed, evaluated, facilitate, cause, coated, 【제목키워드】 COVID-19, Saudi Arabia, HEPA filter, Isolation room,