Rapid genome surveillance of SARS-CoV-2 and study of risk factors using shipping container laboratories and portable DNA sequencing technology (preprint)

ABSTRACT

In this paper we report on genome sequencing of 154 SARS-CoV-2 samples between June and July 2021 (Summer outbreak) in the Bailiwick of Jersey, a UK channel island. We have analysed extensive data collected on 598,155 RT-qPCR tests that identified 8,950 positive cases as part of public health surveillance from September 2020 to August 2021. Our study implemented an amplicon-based sequencing approach using the Oxford Nanopore Technology (ONT) portable device. This revealed the emergence of twelve AY sublineages and were clustered into the Delta sub-clades 21I and 21J. This was integrated alongside an existing RT-qPCR diagnostic laboratory to provide a sample-to-sequence turnaround time of approximately 30 hours with significant scope for optimisation. Owing to the geographic remoteness of the island from large scale sequencing infrastructure, this presents an opportunity to provide policy makers with near real-time sequencing findings. Our analysis suggests that age and sex remained a substantial risk factor for mortality. We observe viral loads are higher in advanced ages and unvaccinated individuals. The median age of SARS-CoV-2 positive individuals was higher during winter than the summer outbreak, and the contact tracing program showed that younger individuals stayed positive for longer.