J Korean Med Sci.  2022 Oct;37(43):e308. 10.3346/jkms.2022.37.e308.

Rates of COVID-19 Infection Among Healthcare Workers in Designated COVID-19 Wards and General Wards

• Jung J
• Kim SK
• Lee Y
• Park S
• Lim YJ
• Kim EO
• Kim SH

• KMID: 2534822
• DOI: http://doi.org/10.3346/jkms.2022.37.e308

Abstract

Background
To evaluate the effects of isolating coronavirus disease 2019 (COVID-19) patients in general wards, we compared the rates of COVID-19 infection in nurses and nursing assistants working in COVID-19 designated wards and in general wards of our hospital from 1 October 2021 to 21 April 2022.
Methods
This study was conducted in a 2,700-bed tertiary care hospital in Seoul, Korea. Designated wards comprised single, negative pressure rooms and a 100% outdoor air system.
Results
During the study period, a total of 2,698 nurses and nursing assistants were employed at our hospital, of whom 310 (11%) were working in the designated wards, and the remaining 2,388 (89%) in the general wards, and among whom 1,158 (43%) were diagnosed with COVID-19. The healthcare workers (HCWs) in the designated wards were less frequently diagnosed with COVID-19 than those in the general wards (31% vs. 45%, P < 0.001). During the period before patients with COVID-19 were isolated in general wards, and during the period after these cases were isolated in general ward, HCWs in designated wards were less frequently infected with the virus than those in general wards (7% vs. 11%, P = 0.039; and 23% vs. 33%, P < 0.001, respectively).
Conclusion
HCWs in designated wards have a lower rate of contracting COVID-19 than those in general wards. A lack of exposure to undiagnosed cases and their caregivers, greater care with social distancing outside the hospital, higher rates of 3-dose vaccinations, and the use of isolation rooms with negative pressure may be associated with this finding.

Keyword

COVID-19; SARS-CoV-2; Healthcare Workers; Isolation

Reference

1. Ministry of Health and Welfare. COVID-19 patients with mild diseases should be treated in a general wards. 2022. Accessed October 4, 2022. http://www.mohw.go.kr/react/al/sal0301vw.jsp?PAR_MENU_ID=04&MENU_ID=0403&page=1&CONT_SEQ=370617 .

2. Korea Disease Control and Prevention Agency. KCDA press release: from February 3, PCR tests will be conducted as priority subjects such as high-risk groups (1.31, regular briefing). Updated 2022. Accessed May 4, 2022. https://www.kdca.go.kr/board/board.es?mid=a20501020000&bid=0015&list_no=718514&cg_code=C01&act=view&nPage=24 .

3. Centers for Disease Control and Prevention (US). Recommended infection prevention and control (IPC) practices when caring for a patient with suspected or confirmed SARS-CoV-2 infection. Updated 2022. Accessed April 28, 2022. https://www.cdc.gov/coronavirus/2019-ncov/hcp/infection-control-recommendations.html .

4. Andrews N, Stowe J, Kirsebom F, Toffa S, Rickeard T, Gallagher E, et al. COVID-19 vaccine effectiveness against the Omicron (B.1.1.529) variant. N Engl J Med. 2022; 386(16):1532–1546. PMID: 35249272.

5. Abu-Raddad LJ, Chemaitelly H, Ayoub HH, AlMukdad S, Yassine HM, Al-Khatib HA, et al. Effect of mRNA vaccine boosters against SARS-CoV-2 Omicron infection in Qatar. N Engl J Med. 2022; 386(19):1804–1816. PMID: 35263534.

6. Klompas M, Baker MA, Rhee C, Tucker R, Fiumara K, Griesbach D, et al. A SARS-CoV-2 cluster in an acute care hospital. Ann Intern Med. 2021; 174(6):794–802. PMID: 33556277.

7. Killingley B, Mann AJ, Kalinova M, Boyers A, Goonawardane N, Zhou J, et al. Safety, tolerability and viral kinetics during SARS-CoV-2 human challenge in young adults. Nat Med. 2022; 28(5):1031–1041. PMID: 35361992.