Environmental Dissemination of SARS-CoV-2 in a University Hospital during the COVID-19 5th Wave Delta Variant Peak in Castile-León, Spain

Priscilla Gomes da Silva; José Gonçalves; Andrés Torres Franco; Elisa Rodriguez; Israel Diaz; Antonio Orduña Domingo; Sonsoles Garcinuño Pérez; Gabriel Alberto March Roselló; Carlos Jesús Dueñas Gutiérrez; Maria São José Nascimento; Sofia I V Sousa; Pedro Garcia Encina; João R Mesquita

doi:10.3390/ijerph20021574

Environmental Dissemination of SARS-CoV-2 in a University Hospital during the COVID-19 5th Wave Delta Variant Peak in Castile-León, Spain

Int J Environ Res Public Health. 2023 Jan 15;20(2):1574. doi: 10.3390/ijerph20021574.

Authors

Priscilla Gomes da Silva^{1

2

3

4

5}, José Gonçalves^{6

7}, Andrés Torres Franco^{6

7}, Elisa Rodriguez^{6

7}, Israel Diaz^{6

7}, Antonio Orduña Domingo⁸, Sonsoles Garcinuño Pérez⁹, Gabriel Alberto March Roselló⁹, Carlos Jesús Dueñas Gutiérrez¹⁰, Maria São José Nascimento¹¹, Sofia I V Sousa^{4

5}, Pedro Garcia Encina^{6

7}, João R Mesquita^{1

2

3}

Affiliations

¹ ICBAS-School of Medicine and Biomedical Sciences, Porto University, 4050-313 Porto, Portugal.
² Epidemiology Research Unit (EPIunit), Institute of Public Health, University of Porto, 1800-412 Porto, Portugal.
³ Laboratório para a Investigação Integrativa e Translacional em Saúde Populacional (ITR), 1800-412 Porto, Portugal.
⁴ LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, 1800-412 Porto, Portugal.
⁵ ALiCE-Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, 1800-412 Porto, Portugal.
⁶ Institute of Sustainable Processes, Valladolid University, Dr. Mergelina S/N., 47011 Valladolid, Spain.
⁷ Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n., 47011 Valladolid, Spain.
⁸ Microbiology Service, Valladolid University Clinical Hospital (HCUV), Faculty of Medicine, University of Valladolid, 47011 Valladolid, Spain.
⁹ Microbiology Service, Valladolid University Clinical Hospital (HCUV), 47011 Valladolid, Spain.
¹⁰ Internal Medicine, Infectious Diseases Section, Valladolid University Clinical Hospital (HCUV), 47011 Valladolid, Spain.
¹¹ Faculty of Pharmacy, University of Porto, 1800-412 Porto, Portugal.

Abstract

The dominant SARS-CoV-2 Delta variant (B.1.617.2) became the main circulating variant among countries by mid 2021. Attention was raised to the increased risk of airborne transmission, leading to nosocomial outbreaks even among vaccinated individuals. Considering the increased number of COVID-19 hospital admissions fueled by the spread of the variant, with Spain showing the highest COVID-19 rates in mainland Europe by July 2021, the aim of this study was to assess SARS-CoV-2 environmental contamination in different areas of a University Hospital in the region of Castile-León, Spain, during the peak of the 5th wave of COVID-19 in the country (July 2021). Air samples were collected from sixteen different areas of the Hospital using a Coriolis^® μ air sampler. Surface samples were collected in these same areas using sterile flocked plastic swabs. RNA extraction followed by a one-step RT-qPCR were performed for detection of SARS-CoV-2 RNA. Of the 21 air samples, only one was positive for SARS-CoV-2 RNA, from the emergency waiting room. Of the 40 surface samples, 2 were positive for SARS-CoV-2 RNA, both from the microbiology laboratory. These results may be relevant for risk assessment of nosocomial infection within healthcare facilities, thus helping prevent and minimize healthcare staff's exposure to SARS-CoV-2, reinforcing the importance of always wearing appropriate and well-fit masks at all times and proper PPE when in contact with infected patients.

Keywords: COVID-19; SARS-CoV-2; air sampling; airborne SARS-CoV-2; airborne transmission; nosocomial transmission.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

COVID-19* / epidemiology
Hospitals, University
Humans
RNA, Viral
SARS-CoV-2 / genetics
Spain / epidemiology

Substances

RNA, Viral

Supplementary concepts

SARS-CoV-2 variants

Grants and funding

This work was supported by national funds, through Fundação para a Ciência e Tecnologia (FCT, Portuguese Foundation for Science and Technology), under projects UIDB/04750/2020 and LA/P/0064/2020, and by LA/P/0045/2020 (ALiCE) and UIDB/00511/2020-UIDP/00511/2020 (LEPABE) funded by national funds through FCT/MCTES (PIDDAC). This work also had financial support from the Regional Government of Castilla y León and the FEDER program (projects CLU 2017-09, UIC315 and VA266P20) and by the Regional Government of Castilla y León and the FEDER program (projects CLU 2017-09, CL-EI-2021-07, UIC315 and VA266P20). This work was also supported by the AIRCOVID initiative and is financed by the EEA Grants Bilateral Relations Fund through the Agreement on the European Economic Area (EEE), Iceland, Liechtenstein and Norway, which are partners in the internal market with the States-Members of the European Union. As a way of promoting a continuous and balanced strengthening of economic and trade relations, the parties to the EEA Agreement established a multi-annual Financial Mechanism, known as EEA Grants. The EEA Grants aim to reduce social and economic disparities in Europe and strengthen bilateral relations between these three countries and the beneficiary countries. For the period 2014–2021, a total contribution of EUR 2.8 billion has been agreed to 15 beneficiary countries. Portugal will benefit from an allocation of EUR 102.7 million. Learn more at eeagrants.gov.pt (accessed on 12 January 2023).