Investigation of SARS-CoV-2 Genome in the Indoor Air and High-Touch Surfaces

Abstract

This study aimed to investigate the presence/absence of SARS-CoV-2 genome in the air and high-touch surfaces. This cross-sectional study was conducted from late-2020 to mid-2021 in the sections of Intensive Care Unit (ICU), emergency, infectious disease ward, and nursing station of the COVID-19 patient reception center in Kerman, Iran. The presence/absence of SARS-CoV-2 genome in the 60 samples of high-touch surfaces and 23 air samples was analyzed by reverse transcription polymerase chain reaction (RT-PCR). Fisher’s exact test was used to compare the number of positive samples in different sampling sites. The genome of SARS-CoV-2 was found in the eight samples (13.32%) taken from the high-touch surfaces (two samples in COVID-19 ICU, two samples in general ICU, two samples in emergency ward, and two samples in nursing station) and two air samples (8.70%) (one sample in the general ICU and one sample in the emergency ward). Statistical analysis showed that there was no significant difference between the type of sampling site and the positive cases of SARS-CoV-2 in the surface samples ( p value = 0.80) and air samples ( p value = 0.22). According to the results, the SARS-CoV-2 can find in the high-touch surfaces and indoor air of the COVID-19 patient reception centers. Therefore, suitable safety and health measures should be taken, including regular and accurate disinfection of surfaces and equipment and proper ventilation to protect healthcare workers and prevent disease transmission. More studies are recommended to investigate the SARS-CoV-2 concentration in the high-touch surfaces and air samples in the similar researches, efficacy of different disinfectants used on the high-touch surfaces and compare the effect of type of ventilation (natural or mechanical) on the viral load.

Detection of infectious SARS-CoV-2 in frozen aerosol samples collected from hospital rooms of patients with COVID-19

“…This is essential to better understand viral resistance to environmental stress, inform on the risks of acquisition in the community and occupational environments and appropriately evaluate virus mitigation methods in indoor settings. Several studies have reported the presence of SARS-CoV-2 RNA in air samples in various settings such as long-term care, acute and intensive care, cars and homes [2][3][4][5]. Unlike molecular methods that allow the quantification of viral genome in air samples, measuring infectious viral particles that may contribute to SARS-CoV-2 transmission is not trivial and has been a technical challenge knowing that the samplers, the environmental context, the time of sampling and the need to store the samples before analysis can strongly influence the quantity of viral particles collected as well as their infectivity [2].…”

Detection of different variants of SARS-CoV-2 RNA (genome) on inanimate surfaces in high-touch public environmental surfaces

“…Among these human HCoVs, four of them including HCoV-OC43, HCoV-229E, HCoV-HKU1, and HCoV-NL63 usually lead to mild to moderate respiratory diseases. SARS-CoV-2 has the third known zoonotic virus, which was spread after SARS-CoV-1 and MERS [1][2][3][4] . It is reported that SARS-CoV-2 encodes more than seven accessory proteins (ORF3a, ORF3b, ORF6, ORF7a, ORF7b, ORF8, and ORF9b), and it should be mentioned that this virus encodes ORF9c and ORF10, which play a role in the immune evasion process 5 .Based on the situation report of WHO, until November 9, 2022, there have been 630,387,858 confirmed cases of COVID-19 (SARS-CoV-2) including 6,583,163 deaths worldwide.…”