Long coronavirus disease (COVID) is a multisystem condition that affects a significant proportion of individuals following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, with persistent symptoms ranging from fatigue and cognitive dysfunction to cardiovascular disorders. It is estimated that 30-60% of infected individuals experience symptoms lasting more than 12 weeks. Despite advances in understanding acute infection, the pathophysiological mechanisms underlying long COVID remain unclear. Current hypotheses suggest that viral persistence, immune dysfunction, and metabolic alterations play central roles. Omics approaches, including metabolomics, proteomics, and lipidomics, have played a crucial role in investigating molecular changes, identifying biomarkers, and refining therapeutic strategies. This review discusses recent advances in understanding long COVID, addressing its mechanisms, risk factors, the impact of viral variants, and the role of vaccination, with an emphasis on the importance of omics technologies in elucidating this condition.