Air and surface measurements of SARS-CoV-2 inside a bus during normal operation

Abstract

Transmission pathways of SARS-CoV-2 are aerosol, droplet and touching infected material. The diffusion of the virus contagion among people is easier in indoor location, but direct detection of SARS-CoV-2 in air or on surfaces is quite sparse, especially regarding public transport, while it would be important to know how and if it is safe to use them. To answer these questions we analysed the air and the surfaces most usually touched by passengers inside a city bus during normal operation, in order to understand the possible spreading of the virus and the effectiveness of the protective measures. The measurements were carried out across the last week of the lockdown and the first week when, gradually, all the travel restrictions were removed. The air and surface samples were analysed with the RT-PCR for the detection of SARS-CoV-2 virus. After two weeks of measurements and more than 1100 passenger travelling on the bus the virus was never detected both on surfaces and on air, suggesting that the precautions adopted on public transportation are effective in reducing the COVID-19 spreading.

Contamination of Air and Surfaces in Workplaces with SARS-CoV-2 Virus: A Systematic Review

“…All but three of the studies were carried out in hospitals, mostly in intensive care settings or isolation wards with COVID-19 patients (75% of the healthcare studies). The three non-healthcare papers describe measurements made on public transportation [buses in Northern Italy ( Di Carlo et al , 2020 ) and buses and subway trains in Spain ( Moreno et al , 2021 )] and various workplaces in Greece [a ferryboat and a nursing home—this paper also included data for three COVID-19 isolation hospital wards and a long-term care facility where 30 asymptomatic COVID-19 cases were located ( Mouchtouri et al , 2020 )]. Most of the studies (77%) aimed to describe the contamination present in the setting investigated and the remainder aimed to investigate the extent of contamination in relation to patient viral load or some other patient-related factors.…”

COVID-19 false dichotomies and a comprehensive review of the evidence regarding public health, COVID-19 symptomatology, SARS-CoV-2 transmission, mask wearing, and reinfection

“…Some studies conducting community-based SARS-CoV-2 RNA detection in air samples have reported negative findings, including those from cruise ship cabins [ 388 ], quarantined households [ 389 ], residential areas [ 354 , 370 ], open public areas [ 354 , 368 ], and transportation [ 368 , 390 ]. In contrast, other studies have reported positive qRT-PCR-positive air samples from a variety of indoor or crowded public spaces [ 370 , 391 ] and transportation [ 391 , 392 ], with SARS-CoV-2 viability not assessed.…”

Effects of Natural Ventilation and Saliva Standard Ejectors during the COVID-19 Pandemic: A Quantitative Analysis of Aerosol Produced during Dental Procedures

“…However, transmission of SARS-CoV-2 through aerosol has been proved, particularly in the presence of highly concentrated aerosols in closed environments [ 2 ]. Evaluations of the air and surfaces in indoor environments [ 3 ] such as restaurants, post offices, pharmacies or in more confined environments such as city buses [ 4 ] are pivotal to better understand SARS-CoV-2 spreading and airborne transmission. In fact, findings suggest that air ventilation and wearing facial masks can further mitigate virus transmission among people [ 5 ].…”