LAUSR

Background: Post-viral syndromes (PVS), including Long COVID, are symptoms sustained from weeks to years following an acute viral infection. Non-pharmacological treatments for these symptoms are poorly understood. This review summarises evidence for the effectiveness of non-pharmacological treatments for symptoms of PVS. It also summarises the symptoms and health impacts of PVS in individuals recruited to studies evaluating treatments. Methods and findings: We conducted a systematic review to evaluate the effectiveness of non-pharmacological interventions for PVS, as compared to either standard care, alternative non-pharmacological therapy, or placebo. The outcomes of interest were changes in symptoms, exercise capacity, quality of life (including mental health and wellbeing), and work capability. We searched five databases (Embase, MEDLINE, PsycINFO, CINAHL, MedRxiv) for randomised controlled trials (RCTs) published between 1st January 2001 to 29th October 2021. We anticipated that there would be few RCTs specifically pertaining to Long COVID, so we also included observational studies only if they assessed interventions in individuals where the viral pathogen was SARS-COV-2. Relevant outcome data were extracted, study quality appraised using the Cochrane Risk of Bias tool, and the findings were synthesised narratively. Quantitative synthesis was not planned due to substantial heterogeneity between the studies. Overall, five studies of five different interventions (Pilates, music therapy, telerehabilitation, resistance exercise, neuromodulation) met the inclusion criteria. Aside from music-based intervention, all other selected interventions demonstrated some support in the management of PVS in some patients. Conclusions: In this study, we observed a lack of robust evidence evaluating non-pharmacological treatments for PVS, including Long COVID. Considering the prevalence of prolonged symptoms following acute viral infections, there is an urgent need for clinical trials evaluating the effectiveness and cost-effectiveness of non-pharmacological treatments for patients with PVS as well as what may work for certain sub-groups of patients with differential symptom presentation. Registration: The study protocol was registered with PROSPERO [CRD42021282074] in October 2021 and published in BMJ Open in 2022. Keywords: Post-viral syndromes, PVS, COVID-19, Long COVID, post-COVID-19 condition, post-acute sequelae of SARS-CoV-2 infection (PASC), rehabilitation, systematic review, non-pharmacological intervention