A one health perspective on the intestinal microbiome's role in COVID-19 outcomes and recovery

Emerging infectious diseases, particularly zoonotic ones, remain major global health concerns. The Coronavirus Disease 2019 (COVID-19) pandemic, caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), highlights the interconnectedness of human, animal, and environmental health within the One Health framework. The intestinal microbiome plays a central role in host immunity and systemic homeostasis, and its disruption has been linked to altered disease severity and recovery patterns in COVID-19. Evidence suggests that SARS-CoV-2 infection induces intestinal dysbiosis, modifies immune signaling, and affects the microbiota-gut-brain axis (MGBA), contributing to neuropsychiatric and metabolic complications. This review synthesizes current findings on the intestinal microbiome's role in COVID-19 pathophysiology and recovery, explores emerging therapeutic strategies including probiotics, prebiotics, and fecal microbiota transplantation, and emphasizes the importance of integrating microbiome research into pandemic preparedness through a One Health approach.