Ann Work Expo Health . SARS-CoV-2 Infection Rates Following Use of Regular Compared With Defective Respirators When Caring for COVID-19 Patients: A Retrospective Follow-up Study

[tetano]

Ann Work Expo Health


. 2022 Apr 30;wxac031.
doi: 10.1093/annweh/wxac031. Online ahead of print.
SARS-CoV-2 Infection Rates Following Use of Regular Compared With Defective Respirators When Caring for COVID-19 Patients: A Retrospective Follow-up Study


Henrik A Kolstad ^{1 2} , Morten Frydenberg ¹ , Kent Jacob Nielsen ³ , Vivi Schlünssen ⁴ , Karin Biering ³ , Mona Kjærsgaard ⁵ , Jesper Medom Vestergaard ¹ , Else Toft Würtz ¹ , Kirsten Pugdahl ¹ , Anne Mette Lund Würtz ⁴ , Karoline Kærgaard Hansen ¹ , Sanne Jespersen ⁶ , Marianne Kragh Thomsen ⁵ , Mette Marie Sørensen ⁶ , Svend Ellermann-Eriksen ⁵ , Jacob Dvinge Redder ⁷ , Merete Storgaard ⁶



Affiliations

• PMID: 35488370
• DOI: 10.1093/annweh/wxac031

Abstract

Background: There is strong observational evidence that respirators are highly effective in protecting the users from being infected with Middle East respiratory syndrome and severe acute respiratory syndrome coronavirus (SARS-CoV), but the evidence for SARS-CoV-2 during daily work is limited. This study utilized a subset of healthcare workers' temporary use of a new brand respirator with frequent defects when caring for coronavirus disease 2019 (COVID-19) patients to assess the protective effect of regular respirators against SARS-CoV-2 infection.
Methods: We retrospectively followed 463 participants wearing a regular respirator and 168 wearing the new brand respirator day-by-day when caring for COVID-19 patients until testing polymerase chain reaction positive for SARS-CoV-2 between 27th December 2020 and 14th January 2021.
Results: We observed seven and eight incident SARS-CoV-2-infected cases. This corresponded with daily infection rates of 0.2 and 0.5%, an incidence rate ratio of 0.4 [95% confidence interval (CI) 0.1; 1.0], and an incidence rate difference of 0.3% (95% CI -0.1; 0.8) when comparing a regular with the new brand respirator.
Discussion: We regard the new brand respirator a sham intervention, and this study thus provides further evidence for the protective effect of respirators when exposed to SARS-CoV-2 virus.

Keywords: SARS-CoV-2; follow-up study; healthcare worker; incidence rate ratio; respirator; sham.