The detection of SARS-CoV-2 RNA in indoor air of dental clinics during the COVID-19 pandemic

Abstract

In the indoor environment of dental clinics, dental personnel and patients are exposed to a risk of infection because of the transmission of SARS-CoV-2 via particles or droplets. This study investigated the presence of SARS-CoV-2 RNA in indoor air of dental clinics in Tehran, Iran. Air sampling was done ( n = 36) collecting particulate samples on PTFE filters at flow rates of 30 to 58 L/min. The samples were analyzed with novel coronavirus nucleic acid diagnostic real-time PCR kits. Only 13 out of 36 samples were positive for SARS-CoV-2 RNA. Logistic regression showed that sampling site’s volume, PM 2.5 concentration, number of people, and number of active patient treatment units were significantly positively related with the presence of SARS-CoV-2 RNA. Thus, strategies to control the spread of COVID-19 should include reducing the number of infected people in dental clinics, adding filtration systems, and/or improving ventilation conditions.

Elucidating the role of environmental management of forests, air quality, solid waste and wastewater on the dissemination of SARS-CoV-2

“…Live SARS-CoV-2 was detected in indoor air of a USA hospital, at a 2 m – 4.8 m distance from patients with at least one positive COVID-19 rRT-PCR test ( Lednicky et al, 2021 ). SARS-CoV-2 RNA has been detected in an exhaust duct surface of a ferry, vehicle air conditioner (AC) and HVAC (Heating, Ventilation and Air Conditioning) filters of dorm and households, and in air samples from health care facilities and patient van, bank, shopping centre, government office, airport, subway station, trains and buses in North and South America, Asia and Europe, due to plausible pollution and lack of air disinfection systems, safe distancing and mask use ( Mouchtouri et al, 2020 ; Lednicky et al, 2020 ; Bazzazpour et al 2021 ; Hadei et al 2021 ; Jin et al, 2021 ; Lednicky et al, 2021 ; Maestre et al, 2021 ; Passos et al 2021 ; Razzini et al 2021; Sousan et al, 2021 ). Similarly, SARS-CoV RNA was detected within indoor air and AC ( Du et al, 2005 ).…”

“…In terms of worldwide research, Bangladesh and Central African Republic are the only least developed countries found to test indoor air for SARS-CoV-2 ( Harries et al, 2020 ; Akter et al, 2021 ; UNDESA, 2021). India, Iran, China, Bosnia and Herzegovina, Brazil, Korea, Lebanon, Malaysia, Vietnam, Russia and Nigeria are the only developing countries found to test or speculate for indoor SARS-CoV-2 ( Kwon et al, 2020 ; Adeniran et al, 2021 ; Alkalamouni et al, 2021 ; Bazzazpour et al 2021 ; Chau et al, 2021 ; Dubey et al, 2021 ; Hu et al, 2021; Hu wang et al, 2021 ; Nor et al, 2021 ; Noureddine et al, 2021 ; Passos et al 2021 ; Pochtovyi et al, 2021 ; Salihefendic et al, 2021 ; World Bank, 2021 ).…”

Development and Application of a Polydimethylsiloxane-Based Passive Air Sampler to Assess Personal Exposure to SARS-CoV-2

“…Recent studies have been successful in detecting airborne SARS-CoV-2 RNA in indoor settings using active sampling methods. 13 − 16 However, the cost, size, and maintenance of these samplers limit their long-term monitoring ability in high-risk transmission areas, including hospital wards, nursing homes, schools, and restaurants. 17 , 18 Moreover, the nonportable nature of many active samplers limits their feasibility as a wearable device for evaluating personal exposures.…”

SARS-CoV-2 and other airborne respiratory viruses in outdoor aerosols in three Swiss cities before and during the first wave of the COVID-19 pandemic

“…Thus, surveillance of virus-laden aerosols is suitable for monitoring this path and assessing qualitative and quantitative molecular epidemiological information on population exposure to SARS-CoV-2 ( Anand et al 2021 ). So far, many studies have detected the presence of SARS-CoV-2 RNA in indoor aerosols, mainly in hospitals ( Ang et al, 2022 , Baboli et al, 2021 , Barbieri et al, 2021 , Bazzazpour et al, 2021 , Cheng et al, 2020 , Chia et al, 2020 , Ding et al, 2021 , Dumont-Leblond et al, 2020 , Feng et al, 2021 , Ghaffari et al, 2021 , Guo et al, 2020 , Habibi et al, 2021 , Hemati et al, 2021 , Kenarkoohi et al, 2020 , Lednicky et al, 2020a , Lednicky et al, 2020b ; Liu et al, 2020 , Lopez et al, 2021 , Nor et al, 2021 , Passos et al, 2021 , Razzini et al, 2020 , Stern et al, 2021a , Stern et al, 2021b ; Tan et al, 2020 , Yarahmadi et al, 2021 , Zhou et al, 2021 ), as well as in residential rooms ( Nannu Shankar et al 2022 ), transportation ( Hadei et al, 2021 , Lednicky et al, 2021 , Moreno et al, 2021 ) and other public indoor places ( Hadei et al 2021 ). Some further detected the presence of SARS-CoV-2 nucleocapsids ( Krambrich et al 2021 ) or even viable viruses ( Lednicky et al, 2020a , Lednicky et al, 2021 ).…”