The Australian Partnership For Preparedness Research on Infectious Disease Emergencies (APPRISE) Long COVID initiative mapping project

Abstract

Australia has established several Long COVID prospective cohort studies, which have used (or attempted to) existing definitions of Long COVID (e.g., WHO, NICE) to determine the prevalence of Long COVID. However, these widely used definitions are primarily intended for clinical purposes. Hence, the use of these definitions has introduced significant ambiguities that hinder research efforts, (e.g., allowing varied stringency in the microbiological confirmation of acute COVID; samples combining cases with minor acute illness impact along with those who are severely disabled). These ambiguities result in variations in Long COVID phenotypes, over- or under-estimation of case rates, spurious findings in pathophysiological research, and limited effectiveness in intervention studies.

Our working research case definition, established through the Australian Partnership For Preparedness Research on Infectious Disease Emergencies (APPRISE) Long COVID Initiative (LCI) (www.apprise.org.au/publication/a-research-definition-for-long-covid/), is more explicit, incorporating specified symptoms, clear disability criteria, and standardised assessments for reliable case confirmation grounded in the post-infective fatigue syndrome framework for which diagnostic criteria already exist.

The aim of the APPRISE LCI mapping project is to:

1. Conduct a retrospective Long COVID systematic review to identify all existing Australian (current & completed) prospective cohorts (and nested cross-sectional studies), and describe outcomes including which Long COVID definition was used and how it was operationalised.
2. Perform a quality assessment of each cohort study and their Long COVID definition.
3. Undertake embedded late follow-up of Long COVID cases in adults and children in partnership with cohort investigators using the APPRISE Long COVID research case definition in the high-quality rated studies.