Comprehensive Review of COVID-19: Epidemiology, Pathogenesis, Diagnostic Advancements, and Post-pandemic Strategies

Background: Since its emergence in late 2019, Coronavirus Disease 2019 (COVID-19), caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), has fundamentally altered global health landscapes. This review aims to synthesize current knowledge regarding the etiology, complex pathogenesis, evolving diagnostic modalities, and updated therapeutic strategies, with a focus on post-pandemic management and Long COVID. A narrative review was conducted using databases including PubMed, Scopus, and WHO repositories. Data regarding epidemiology, pathophysiology, and clinical guidelines published between January 2020 and late 2024 were analyzed. The virus utilizes the ACE2 receptor for entry, triggering a dysregulated immune response (cytokine storm) and coagulopathy. Diagnostic techniques have evolved from standard RT-PCR to rapid molecular assays and AI-assisted imaging. Treatment has shifted from supportive care to targeted antivirals and immunomodulators. While acute mortality has decreased due to vaccination and population immunity, the focus must now shift to managing endemic transmission and the chronic sequelae known as Post-Acute Sequelae of SARS-CoV-2 (PASC).