COVID-19: History, Etiology, Epidemiology, and Pathogenesis


  • Tsvetko Vasilev Grigorov Medical Faculty of Sofia Medical University 27, Nikolay Liliev Str, Sofia Bulgaria


COVID-19, SARS-CoV-2, 16s rRNA, S protein, M protein, N protein, antibodies, immune response, interleukins, lymphocytes, renin-angiotensin-aldosterone system


The 2019 coronavirus disease (COVID-19) is an infectious disease caused by the virus SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2). The first case of the disease was identified in Wuhan, China, in December 2019. The disease quickly spread around the world as a pandemic.

COVID-19 is transmitted by breathing in air droplets and other small particles that contain the virus. Infection occurs most often when people are in close proximity, but it can also happen at greater distances between them, especially indoors. Spread of the disease can also occur by entry of contaminated fluids into the eyes, nose, or mouth, and less commonly through contaminated surfaces. Affected individuals carry the virus for up to 20 days and can spread it even if they do not develop the disease symptoms.


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How to Cite

Grigorov, T. V. . (2023). COVID-19: History, Etiology, Epidemiology, and Pathogenesis. American Scientific Research Journal for Engineering, Technology, and Sciences, 92(1), 153–159. Retrieved from