# Assessment of SARS-CoV-2 genome sequence recovery from four lateral flow device products available in the UK

## TL;DR

This paper evaluates the ability to recover and sequence SARS-CoV-2 RNA from lateral flow tests used in the UK, finding it feasible but with variation between devices.

## Contribution

The study demonstrates the feasibility of recovering SARS-CoV-2 RNA from lateral flow devices for sequencing, while highlighting the need for device optimization.

## Key findings

- Sequencing from LFD eluates is possible at clinically relevant titres.
- Results varied across the four tested devices.
- Sequences obtained were consistent with routine methods.

## Abstract

Introduction. Lateral flow tests have played a key role in the response to the COVID-19 pandemic and are likely to be a major component of diagnostic strategies to combat future outbreaks of infectious disease.

Gap Statement. One challenge posed by widescale use of lateral flow tests in the community is the loss of sequence information to track virus evolution and epidemiology.

Aim. Beyond their primary diagnostic function, it has been demonstrated that recovery of viral RNA from positive lateral flow devices (LFDs) for genome sequencing purposes is possible. We, therefore, aimed to assess the robustness and broader applicability of this process.

Methodology. We evaluated SARS-CoV-2 RNA recovery and subsequent sequencing from eluates from the four major LFDs in use in the UK, testing both cultured virus and residual clinical nasal swab samples.

Results. Our results demonstrated that sequencing from LFD eluates is possible, at clinically relevant titres, within a reasonable processing time frame post-use, and gave sequences concordant with routine methods. However, results varied across the four devices used.

Conclusion. Our results highlight that if sequencing from LFD eluates is to be put into routine use, there is the requirement for refinement of existing or second-generation designs, optimized for sequencing as an intended output from positive tests.