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Unravelling the Role of the Mandatory Use of Face Covering Masks for the Control of SARS-CoV-2 in Schools: A Quasi-Experimental Study Nested in a Population-Based Cohort in Catalonia (Spain)

28 Pages Posted: 8 Mar 2022

See all articles by Ermengol Coma

Ermengol Coma

Institut Català de la Salut - Sistemes d’Informació dels Serveis d’Atenció Primària (SISAP)

Marti Catala

Polytechnic University of Catalonia (UPC) - Computational Biology and Complex Systems (BIOCOM-SC); University of Oxford - Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS)

Leonardo Méndez-Boo

Institut Català de la Salut - Sistemes d’Informació dels Serveis d’Atenció Primària (SISAP)

Sergio Alonso

Polytechnic University of Catalonia (UPC) - Department of Physics

Eduardo Hermosilla

Institut Català de la Salut - Sistemes d’Informació dels Serveis d’Atenció Primària (SISAP)

Enric Alvarez-Lacalle

Polytechnic University of Catalonia (UPC) - Department of Physics

David Pino

Polytechnic University of Catalonia (UPC) - Department of Physics

Manuel Medina

Institut Català de la Salut - Sistemes d’Informació dels Serveis d’Atenció Primària (SISAP)

Laia Asso

Generalitat de Catalunya - Secretary of Public Health

Anna Gatell

Alt Penedès-Garraf Territorial Pediatric Team

Quique Bassat

University of Barcelona - Institut de Salut Global de Barcelona (ISGlobal)

Ariadna Mas

Generalitat de Catalunya - Healthcare Directorate of Primary Care and the Community

Antoni Soriano-Arandes

Autonomous University of Barcelona - Paediatric Infectious Diseases and Immunodeficiencies Unit

Francesc Fina-Aviles

Institut Català de la Salut - Sistemes d’Informació dels Serveis d’Atenció Primària (SISAP)

Clara Prats

Polytechnic University of Catalonia (UPC) - Computational Biology and Complex Systems (BIOCOM-SC)

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Abstract

Background: Mandatory use of face covering masks (FCM) had been established for children aged six and above in Catalonia (Spain), as one of the non-pharmaceutical interventions aimed at mitigating SARS-CoV-2 transmission within schools. To date, the effectiveness of this mandate has not been well established. The quasi-experimental comparison between 5 year-old children, as a control group, and 6 year-old children, as an interventional group, provides us with the appropriate research conditions for addressing this issue.

Methods: We performed a retrospective population-based study among 599,314 children aged 3 to 11 years attending preschool (3-5 years, without FCM mandate) and primary education (6-11 years, with FCM mandate) with the aim of calculating the incidence of SARS-CoV-2, secondary attack rates (SAR) and the effective reproductive number (R*) for each grade during the first trimester of the 2021-2022 academic year, and analysing the differences between 5-year-old, without FCM, and 6 year-old children, with FCM.

Findings: SARS-CoV-2 incidence was significantly lower in preschool than in primary education, and an age-dependent trend was observed. Children aged 3 and 4 showed lower outcomes for all the analysed epidemiological variables, while children aged 11 had the higher values. Six-year-old children showed higher incidence than 5 year-olds (3·54% vs 3·1%; OR: 1·15 [95%CI: 1·08-1·22]) and slightly lower but not statistically significant SAR and R*: SAR were 4·36% in 6 year-old children, and 4·59% in 5 year-old (IRR: 0·96 [95%CI: 0·82-1·11]); and R* was 0·9 and 0·93 (OR: 0·96 [95%CI: 0·87-1·09]), respectively.

Interpretation: FCM mandates in schools were not associated with lower SARS-CoV-2 incidence or transmission, suggesting that this intervention was not effective. Instead, age-dependency was the most important factor in explaining the transmission risk for children attending school.

Funding Information: CP and SA received funding from Ministerio de Ciencia, Innovación y Universidades and FEDER, with the project PGC2018-095456-B-I00.

Declaration of Interests: The authors declare that they have no conflict of interests.

Ethics Approval Statement: The study was evaluated and approved by the Clinical Research Ethics Committee of the IDIAP Jordi Gol, Reference 21/018-PCV. This research was based on the agreement established in Regulation 2016/679 of the European Parliament and the Council of Europe of 27 April 2016 on Data Protection, and Organic Law 3/2018 of December 5 on the protection of personal data and the guarantee of digital rights.

Keywords: COVID-19, SARS-CoV-2, Child, Epidemiology, Schools, Incidence

Suggested Citation

Coma, Ermengol and Catala, Marti and Méndez-Boo, Leonardo and Alonso, Sergio and Hermosilla, Eduardo and Alvarez-Lacalle, Enric and Pino, David and Medina, Manuel and Asso, Laia and Gatell, Anna and Bassat, Quique and Mas, Ariadna and Soriano-Arandes, Antoni and Fina-Aviles, Francesc and Prats, Clara, Unravelling the Role of the Mandatory Use of Face Covering Masks for the Control of SARS-CoV-2 in Schools: A Quasi-Experimental Study Nested in a Population-Based Cohort in Catalonia (Spain). Available at SSRN: https://ssrn.com/abstract=4052659 or http://dx.doi.org/10.2139/ssrn.4052659

Ermengol Coma

Institut Català de la Salut - Sistemes d’Informació dels Serveis d’Atenció Primària (SISAP) ( email )

Barcelona
Spain

Marti Catala

Polytechnic University of Catalonia (UPC) - Computational Biology and Complex Systems (BIOCOM-SC) ( email )

Castelldefels
Spain

University of Oxford - Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS) ( email )

Oxford
United Kingdom

Leonardo Méndez-Boo

Institut Català de la Salut - Sistemes d’Informació dels Serveis d’Atenció Primària (SISAP)

Barcelona
Spain

Sergio Alonso

Polytechnic University of Catalonia (UPC) - Department of Physics ( email )

Castelldefels
Spain

Eduardo Hermosilla

Institut Català de la Salut - Sistemes d’Informació dels Serveis d’Atenció Primària (SISAP) ( email )

Barcelona
Spain

Enric Alvarez-Lacalle

Polytechnic University of Catalonia (UPC) - Department of Physics ( email )

Castelldefels
Spain

David Pino

Polytechnic University of Catalonia (UPC) - Department of Physics ( email )

Castelldefels
Spain

Manuel Medina

Institut Català de la Salut - Sistemes d’Informació dels Serveis d’Atenció Primària (SISAP) ( email )

Barcelona
Spain

Laia Asso

Generalitat de Catalunya - Secretary of Public Health ( email )

Spain

Anna Gatell

Alt Penedès-Garraf Territorial Pediatric Team ( email )

Spain

Quique Bassat

University of Barcelona - Institut de Salut Global de Barcelona (ISGlobal) ( email )

Barcelona
Spain

Ariadna Mas

Generalitat de Catalunya - Healthcare Directorate of Primary Care and the Community ( email )

Barcelona
Spain

Antoni Soriano-Arandes (Contact Author)

Autonomous University of Barcelona - Paediatric Infectious Diseases and Immunodeficiencies Unit ( email )

Barcelona
Spain
+34639712438 (Phone)

Francesc Fina-Aviles

Institut Català de la Salut - Sistemes d’Informació dels Serveis d’Atenció Primària (SISAP) ( email )

Barcelona
Spain

Clara Prats

Polytechnic University of Catalonia (UPC) - Computational Biology and Complex Systems (BIOCOM-SC) ( email )

Castelldefels
Spain