Epidemiology of COVID-19 outbreaks in aged care facilities during postvaccine period: a systematic review and meta-analysis

Mohammad Rashidul Hashan; Nicolas Smoll; Gwenda Chapman; Catherine King; Jacina Walker; Michael Kirk; Delwar Akbar; Robert Booy; Gulam Khandaker

doi:10.1136/bmjopen-2023-073555

Epidemiology of COVID-19 outbreaks in aged care facilities during postvaccine period: a systematic review and meta-analysis

BMJ Open. 2024 Mar 14;14(3):e073555. doi: 10.1136/bmjopen-2023-073555.

Authors

Mohammad Rashidul Hashan^{1

2}, Nicolas Smoll³, Gwenda Chapman², Catherine King⁴, Jacina Walker², Michael Kirk³, Delwar Akbar⁵, Robert Booy⁶, Gulam Khandaker^{7

8}

Affiliations

¹ Central Queensland University, Rockhampton, Queensland, Australia.
² Central Queensland Public Health Unit, Central Queensland Hospital and Health Service, Rockhampton, Queensland, Australia.
³ Central Queensland Hospital and Health Service, Rockhampton, Queensland, Australia.
⁴ The University of Sydney Faculty of Medicine and Health, Sydney, New South Wales, Australia.
⁵ School of Business and Law, Central Queensland University, Rockhampton, Queensland, Australia.
⁶ National Centre for Immunisation Research and Surveillance of Vaccine Preventable Diseases, Westmead, New South Wales, Australia.
⁷ Central Queensland Public Health Unit, Central Queensland Hospital and Health Service, Rockhampton, Queensland, Australia gulam.khandaker@health.qld.gov.au.
⁸ Research Division, Central Queensland University, Rockhampton, Queensland, Australia.

Abstract

Objective: We aimed to define the epidemiology of COVID-19 outbreaks in aged care facilities (ACFs) during the postvaccine period, including vaccine effectiveness (VE) for this high-risk group.

Design: Systematic review and meta-analysis.

Data sources: Ovid Medline, Ovid Embase, Scopus, Web of Science and Cochrane databases were searched through 1 September 2023.

Eligibility criteria: Any original observational studies and trials reporting data on COVID-19 outbreaks among the partially/fully vaccinated residents from ACFs during or after the worldwide implementation of vaccine roll-out.

Data extraction and synthesis: We estimated the attack rate, case fatality rate, mortality rate and VE during postvaccine period. Random effect model was adopted for meta-analysis. Quality assessment on all included studies was performed using the Meta Quality Appraisal Tool.

Results: 38 articles were included from 12 countries reporting 79 outbreaks with 1708 confirmed cases of COVID-19 from 78 ACFs. The pooled attack rate was 28% (95% CI 20% to 37%) among the fully vaccinated residents. Two-thirds (62.5%) of the index cases were unvaccinated healthcare professionals (eg, physicians, nurses) and caregivers. Unvaccinated residents had a significantly higher rates (12%) (95% CI 7% to 19%) of mortality compared with the vaccinated residents (2%) (95% CI% 1 to 4%) and the post-COVID-19 vaccine estimates for case fatality rate (13% vs 23%) and hospitalisation rate (17% vs 37%) were substantially lower. VE in preventing disease among residents in ACFs was 73% (95% CI 49% to 86). Overall, the included studies were heterogeneous in nature, however, the risk of bias was low to moderate.

Conclusions: Our study reaffirmed the impact of vaccination as a key public health measure to minimise the burden of COVID-19 in ACFs. Facilities with higher crowding indexes should be prioritised for vaccination and should advocate for higher vaccination targets among staff and residents as a critical intervention strategy to minimise disease burden in this vulnerable population.

Keywords: Aged; COVID-19; EPIDEMIOLOGY; Public health; Systematic Review.

Publication types

Meta-Analysis
Systematic Review

MeSH terms

Aged
COVID-19 Vaccines
COVID-19* / epidemiology
COVID-19* / prevention & control
Disease Outbreaks / prevention & control
Health Personnel
Humans
Vaccination

Substances

COVID-19 Vaccines