Evaluating Social and Spatial Inequalities of Large Scale Rapid Lateral Flow SARS-CoV-2 Antigen Testing in COVID-19 Management: An Observational Study of Liverpool, UK (November 2020 to January 2021)

Abstract

Background: The aim of the study is to explore social and spatial inequalities in uptake and case-detection of rapid lateral flow SARS-CoV-2 antigen tests (LFTs) offered to people without symptoms of COVID-19.

Methods: Linked pseudonymised records for asymptomatic residents in Liverpool (UK) who received a LFT for COVID-19 between 6^th November 2020 to 31^st January 2021 were accessed using the Combined Intelligence for Population Health Action (CIPHA) data resource. Bayesian Hierarchical Poisson Besag, York, and Mollié models were used to estimate ecological associations for uptake and positivity of testing.

Findings: 214 525 residents (43%) received a LFT identifying 5557 individuals as positive cases of COVID-19 (1.3%). Uptake was highest in November when there was military assistance. High uptake was observed again in the week preceding Christmas and was sustained into a national lockdown. Overall uptake and repeat testing were lower among males (e.g. 40% uptake over the whole period), Black Asian and other Minority Ethnic groups (e.g. 27% uptake for ‘Mixed’ ethnicity) and in the most deprived areas (e.g. 32% uptake in most deprived areas). These population groups were also more likely to have received positive tests for COVID-19. Models demonstrated that uptake and repeat testing were lower in areas of higher deprivation, areas located further from test sites and areas containing populations less confident in the using Internet technologies. Positive tests were spatially clustered in deprived areas.

Interpretation: Large-scale voluntary asymptomatic community testing saw social, ethnic, and spatial inequalities in an ‘inverse care’ pattern, but with an added digital exclusion factor. COVID-19 testing and support to isolate need to be more accessible to the vulnerable communities most impacted by the pandemic, including non-digital means of access.

Funding: Department of Health and Social Care (UK), National Institute for Health Research and Economic and Social Research Council).

Conflict of Interest: None declared.

Ethical Approval: The University of Liverpool has provided secondary data analysis as part of a national service evaluation with data collected by Department of Health and Social Care (Sponsor) for quality assurance of Innova lateral flow tests in a public health service intervention. There was no research commissioned by Department of Health and Social Care on this aspect of the Liverpool pilot of asymptomatic, community testing. As such, research ethics approval was not sought by the Department of Health and Social Care. Some aspects of the evaluation requiring fieldwork and primary data collection by the University of Liverpool were subject to ethical approval, which was confirmed prior to the commencement of activities by the University of Liverpool’s Research Ethics Committee. The provision of secondary data analysis and interpretation did not require further ethical approval. Cheshire & Merseyside Health & Care Partnership Combined Intelligence for Population HealthAction (CIPHA) Data Access Committee approved access to the data and analysis contained in the study. MAST/SMART was defined as ‘an emergency public health intervention during an extraordinary event’ which were subject to the legal and ethical provisions of a health protection activity and COVID-19 specifically. The secondary analysis of data provided in a health protection activity is not classified as research, and so does not require research ethics committee review (see http://www.hradecisiontools.org.uk/research/docs/DefiningResearchTable_Oct2017-1.pdf).