Horses for courses? Assessing the potential value of a surrogate,
point-of-care test for SARS-CoV2 epidemic control
Abstract
Point-of-care tests (POCTs) offer considerable potential for improving
clinical and public health management of COVID-19 by providing timely
information to guide decision-making, but data on real-world performance
are in short supply. Besides SARS-CoV2-specific tests, there is growing
interest in the role of surrogate (non-specific) tests such as FebriDx,
a biochemical POCT which can be used to distinguish viral from bacterial
infection in patients with influenza-like illnesses. This short
communication assesses what is currently known about FebriDx performance
across settings and populations by comparison with some of the more
intensively evaluated SARS-CoV2-specific POCTs. While FebriDx shows some
potential in supporting triage for early-stage infection in acute care
settings, this is dependent on SARS-CoV2 being the most likely cause for
influenza-like illnesses, with reduction in discriminatory power when
COVID-19 case numbers are low, and when co-circulating viral respiratory
infections become more prevalent during the autumn and winter. Too
little is currently known about its performance in primary care and the
community to support use in these contexts and further evaluation is
needed. Reliable SARS CoV2-specific POCTs – when they become available
– are likely to rapidly overtake surrogates as the preferred option
given the greater specificity they provide.