What is Long COVID?

Long COVID is an infection-associated chronic condition that develops after a SARS-CoV-2 infection and is present for at least three months as a continuous, relapsing and remitting, or progressive disease state. Internationally, there are several definitions of Long COVID, though the Ministry of Health and Family Welfare of India clinically defines Long COVID as signs and symptoms lasting over 12 weeks after a COVID-19 infection that do not have an alternative diagnosis. Long COVID can last years or may be lifelong, and can have a profound impact on quality of life. Anyone is at risk of developing Long COVID, including people who have been vaccinated for SARS-CoV-2. Multiple COVID-19 infections increase this risk. It is estimated that at least 400 million people worldwide had Long COVID in 2023. People with Long COVID may experience one to multiple symptoms affecting several organ systems. Common symptoms include fatigue, cognitive dysfunction, post- exertional symptom exacerbation (PESE) (also known as post-exertional malaise or PEM), headaches, insomnia, and joint and muscle aches. Although the mechanisms that cause Long COVID are still being understood, research advances have found evidence of multiple and potentially overlapping pathophysiologies, which may include immune dysregulation and autoimmunity, persistence of SARS-CoV-2 in reservoir sites, reactivation of latent viral infections, neurological abnormalities and neuroinflammation, tissue and organ damage, vascular dysfunction and endothelial disease, fibrin amyloid microclots, and microbiome dysregulation. Despite advances in the understanding of Long COVID, there are no approved treatments or cures, and no standardized care pathways. Clinical management of Long COVID has been focused on providing symptom management and controlling comorbidities. Healthcare for people with Long COVID widely varies worldwide across different health systems and patient demographics, but most patients are suffering with nil to minimal social support and care.