Emerging Evidence on Balneotherapy and Thermal Interventions in Post-COVID-19 Syndrome: A Systematic Review

Background: Post-COVID-19 syndrome affects 10–60% of SARS-CoV-2 survivors. While conventional treatments show limited efficacy, emerging evidence suggests the potential benefits of balneotherapy in managing persistent symptoms. We aimed to systematically evaluate the efficacy and safety of balneotherapy and thermal treatment interventions in treating post-COVID-19 syndrome. Methods: We conducted a systematic review following PRISMA guidelines, searching major databases through 31 January 2024. Eligible studies included randomized controlled trials, observational studies, and pilot studies investigating thermal spa treatments for adult post-COVID-19 patients. Results: Analysis of six eligible studies (n = 617) demonstrated significant therapeutic benefits. The largest cohort (n = 159) showed 47% reduction in fatigue and 48% reduction in muscle pain (p < 0.01). Comprehensive spa therapy achieved complete symptom resolution in one-third of the participants. Combined spa-ubiquinol therapy improved metabolic function (p < 0.05). All interventions demonstrated favorable safety profiles. Conclusions: Preliminary evidence suggests balneotherapy effectively ameliorates multiple post-COVID-19 symptoms, particularly fatigue, muscle pain, and exercise intolerance. While safety profiles appear favorable, larger randomized controlled trials with standardized protocols are needed to establish definitive therapeutic recommendations.