Evidence of the presence of SARS-CoV-2 virus in atmospheric air and surfaces of a dedicated COVID hospital.

The present study was conducted from July 1, 2020 to September 25, 2020 in a dedicated coronavirus disease 2019 (COVID-19) hospital in Delhi, India to provide evidence for the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus in atmospheric air and surfaces of the hospital wards. Swabs from hospital surfaces (patient's bed, ward floor, and nursing stations area) and suspended particulate matter in ambient air were collected by a portable air sampler from the medicine ward, intensive care unit, and emergency ward admitting COVID-19 patients. By performing reverse-transcriptase polymerase chain reaction (RT-PCR) for E-gene and RdRp gene, SARS-CoV-2 virus was detected from hospital surfaces and particulate matters from the ambient air of various wards collected at 1 and 3-m distance from active COVID-19 patients. The presence of the virus in the air beyond a 1-m distance from the patients and surfaces of the hospital indicates that the SARS-CoV-2 virus has the potential to be transmitted by airborne and surface routes from COVID-19 patients to health-care workers working in COVID-19 dedicated hospital. This warrants that precautions against airborne and surface transmission of COVID-19 in the community should be taken when markets, industries, educational institutions, and so on, reopen for normal activities.

Dubey A ，Kotnala G ，Mandal TK ，Sonkar SC ，Singh VK ，Guru SA ，Bansal A ，Irungbam M ，Husain F ，Goswami B ，Kotnala RK ，Saxena S ，Sharma SK ，Saxena KN ，Sharma C ，Kumar S ，Aswal DK ，Manchanda V ，Koner BC ... -  《-》

Monitoring COVID-19 Transmission Risks by Quantitative Real-Time PCR Tracing of Droplets in Hospital and Living Environments.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) environmental contamination occurs through droplets and biological fluids released in the surroundings from patients or asymptomatic carriers. Surfaces and objects contaminated by saliva or nose secretions represent a risk for indirect transmission of coronavirus disease 2019 (COVID-19). We assayed surfaces from hospital and living spaces to identify the presence of viral RNA and the spread of fomites in the environment. Anthropic contamination by droplets and biological fluids was monitored by detecting the microbiota signature using multiplex quantitative real-time PCR (qPCR) on selected species and massive sequencing on 16S amplicons. A total of 92 samples (flocked swabs) were collected from critical areas during the pandemic, including indoor (three hospitals and three public buildings) and outdoor surfaces exposed to anthropic contamination (handles and handrails, playgrounds). Traces of biological fluids were frequently detected in spaces open to the public and on objects that are touched with the hands (>80%). However, viral RNA was not detected in hospital wards or other indoor and outdoor surfaces either in the air system of a COVID hospital but only in the surroundings of an infected patient, in consistent association with droplet traces and fomites. Handled objects accumulated the highest level of multiple contaminations by saliva, nose secretions, and fecal traces, further supporting the priority role of handwashing in prevention. In conclusion, anthropic contamination by droplets and biological fluids is widespread in spaces open to the public and can be traced by qPCR. Monitoring fomites can support evaluation of indirect transmission risks for coronavirus or other flu-like viruses in the environment.IMPORTANCE Several studies have evaluated the presence of SARS-CoV-2 in the environment. Saliva and nasopharyngeal droplets can land on objects and surfaces, creating fomites. A suitable indicator would allow the detection of droplets or biofluids carrying the virus. Therefore, we searched for viral RNA and droplets and fomites on at risk surfaces. We monitored by qPCR or next generation sequencing (NGS) droplets through their microbiota. Although the study was performed during the pandemic, SARS-CoV-2 was not significantly found on surfaces, with the only exception of environmental areas near infectious patients. Conversely, anthropic contamination was frequent, suggesting a role for biofluids as putative markers of indirect transmission and risk assessment. Moreover, all SARS-CoV-2-contaminated surfaces showed droplets' microbiota. Fomite monitoring by qPCR may have an impact on public health strategies, supporting prevention of indirect transmission similarly to what is done for other communicable diseases (e.g., influenza and influenza-like infections).

Piana A ，Colucci ME ，Valeriani F ，Marcolongo A ，Sotgiu G ，Pasquarella C ，Margarucci LM ，Petrucca A ，Gianfranceschi G ，Babudieri S ，Vitali P ，D'Ermo G ，Bizzarro A ，De Maio F ，Vitali M ，Azara A ，Romano F ，Simmaco M ，Romano Spica V ... -  《mSphere》

Detection of SARS-CoV-2 within the healthcare environment: a multi-centre study conducted during the first wave of the COVID-19 outbreak in England.

Understanding how severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is spread within the hospital setting is essential in order to protect staff, implement effective infection control measures, and prevent nosocomial transmission. The presence of SARS-CoV-2 in the air and on environmental surfaces around hospitalized patients, with and without respiratory symptoms, was investigated. Environmental sampling was undertaken within eight hospitals in England during the first wave of the coronavirus disease 2019 outbreak. Samples were analysed using reverse transcription polymerase chain reaction (PCR) and virus isolation assays. SARS-CoV-2 RNA was detected on 30 (8.9%) of 336 environmental surfaces. Cycle threshold values ranged from 28.8 to 39.1, equating to 2.2 x 105 to 59 genomic copies/swab. Concomitant bacterial counts were low, suggesting that the cleaning performed by nursing and domestic staff across all eight hospitals was effective. SARS-CoV-2 RNA was detected in four of 55 air samples taken <1 m from four different patients. In all cases, the concentration of viral RNA was low and ranged from <10 to 460 genomic copies/m3 air. Infectious virus was not recovered from any of the PCR-positive samples analysed. Effective cleaning can reduce the risk of fomite (contact) transmission, but some surface types may facilitate the survival, persistence and/or dispersal of SARS-CoV-2. The presence of low or undetectable concentrations of viral RNA in the air supports current guidance on the use of specific personal protective equipment for aerosol-generating and non-aerosol-generating procedures.

Moore G ，Rickard H ，Stevenson D ，Aranega-Bou P ，Pitman J ，Crook A ，Davies K ，Spencer A ，Burton C ，Easterbrook L ，Love HE ，Summers S ，Welch SR ，Wand N ，Thompson KA ，Pottage T ，Richards KS ，Dunning J ，Bennett A ... -  《-》

Surface and Air Contamination With Severe Acute Respiratory Syndrome Coronavirus 2 From Hospitalized Coronavirus Disease 2019 Patients in Toronto, Canada, March-May 2020.

We determined the burden of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in air and on surfaces in rooms of patients hospitalized with coronavirus disease 2019 (COVID-19) and investigated patient characteristics associated with SARS-CoV-2 environmental contamination. Nasopharyngeal swabs, surface, and air samples were collected from the rooms of 78 inpatients with COVID-19 at 6 acute care hospitals in Toronto from March to May 2020. Samples were tested for SARS-CoV-2 ribonucleic acid (RNA), cultured to determine potential infectivity, and whole viral genomes were sequenced. Association between patient factors and detection of SARS-CoV-2 RNA in surface samples were investigated. Severe acute respiratory syndrome coronavirus 2 RNA was detected from surfaces (125 of 474 samples; 42 of 78 patients) and air (3 of 146 samples; 3 of 45 patients); 17% (6 of 36) of surface samples from 3 patients yielded viable virus. Viral sequences from nasopharyngeal and surface samples clustered by patient. Multivariable analysis indicated hypoxia at admission, polymerase chain reaction-positive nasopharyngeal swab (cycle threshold of ≤30) on or after surface sampling date, higher Charlson comorbidity score, and shorter time from onset of illness to sampling date were significantly associated with detection of SARS-CoV-2 RNA in surface samples. The infrequent recovery of infectious SARS-CoV-2 virus from the environment suggests that the risk to healthcare workers from air and near-patient surfaces in acute care hospital wards is likely limited.

Kotwa JD ，Jamal AJ ，Mbareche H ，Yip L ，Aftanas P ，Barati S ，Bell NG ，Bryce E ，Coomes E ，Crowl G ，Duchaine C ，Faheem A ，Farooqi L ，Hiebert R ，Katz K ，Khan S ，Kozak R ，Li AX ，Mistry HP ，Mozafarihashjin M ，Nasir JA ，Nirmalarajah K ，Panousis EM ，Paterson A ，Plenderleith S ，Powis J ，Prost K ，Schryer R ，Taylor M ，Veillette M ，Wong T ，Zoe Zhong X ，McArthur AG ，McGeer AJ ，Mubareka S ... -  《-》

Quantification of airborne SARS-CoV-2 genomic particles in different hospital settings.

We quantified the presence of SARS-CoV-2 RNA in the air of different hospital settings and the autopsy room of the largest medical centre in Sao Paulo, Brazil. Real-time reverse-transcription PCR was used to determine the presence of the envelope protein of SARS-CoV-2 and the nucleocapsid protein genes. The E-gene was detected in 5 out of 6 samples at the ICU-COVID-19 ward and in 5 out of 7 samples at the ward-COVID-19. Similarly, in the non-dedicated facilities, the E-gene was detected in 5 out of 6 samples collected in the ICU and 4 out of 7 samples in the ward. In the necropsy room, 6 out of 7 samples were positive for the E-gene. When both wards were compared, the non-COVID ward presented a significantly higher concentration of the E-gene than in the COVID-19 ward (p = 0.003). There was no significant difference in E-gene concentration between the ICU-COVID-19 and the ICU (p = 0.548). Likewise, there was no significant difference among E-gene concentrations found in the autopsy room versus the ICUs and wards (dedicated or not) (p = 0.245). Our results show the widespread presence of aerosol contamination in different hospital units.

Amato-Lourenço LF ，de Souza Xavier Costa N ，Dantas KC ，Lombardi SCFS ，Júnior AM ，Lindoso JAL ，Lima FG ，Carvalho-Oliveira R ，Mauad T ... -  《Scientific Reports》