A review of what is known about COVID-19 and the way it functions suggests the virus has a unique infectious profile, which explains why it can be so hard to treat and why some people experience so-called “long COVID,” struggling with significant health issues months after infection, Medical Xpress reports. Growing evidence indicates that the virus infects the upper and lower respiratory tracts — unlike “low pathogenic” human coronavirus sub-species, which typically settle in the upper respiratory tract and cause cold-like symptoms, or “high pathogenic” viruses such as those that cause SARS and ARDS, which typically settle in the lower respiratory tract. Additionally, more frequent multi-organ impacts, blood clots, and an unusual immune-inflammatory response not commonly associated with similar viruses mean that COVID-19 has evolved a uniquely challenging set of characteristics.
https://medicalxpress.com/news/2021-05-covid-hard-evidence-unique-infectious.html
