Internet Book of Critical Care (IBCC)

Basics
  • COVID-19 is a non-segmented, positive sense RNA virus.
  • COVID-19 is part of the family of coronaviruses.  This contains:
    • (i) Four coronaviruses which are widely distributed and usually cause the common cold (but can cause viral pneumonia in patients with comorbidities).
    • (ii) SARS and MERS – these caused epidemics with high mortality which are somewhat similar to COVID-19.  COVID-19 is most closely related to SARS.
  • COVID-19 binds via the angiotensin-converting enzyme 2 (ACE2) receptor located on type II alveolar cells,  intestinal epithelia, and the vascular endothelium (Hamming 2004).
    • This is the same receptor as used by SARS (hence the technical name for the COVID-19, “SARS-CoV-2”).
    • When considering possible therapies, SARS (a.k.a. “SARS-CoV-1”) is the most closely related virus to COVID-19.
  • COVID-19 is mutating, which may complicate matters even further.  Virulence and transmission will shift over times, in ways which we cannot predict.  Ongoing phylogenetic mapping of new strains can be found here.

For complete book Access: