Scientific Name: severe acute respiratory syndrome coronavirus 2
The surface has viral proteins which bind to cell surfaces in host. A lipid bilayer encapsulates the RNA.
There are few types of tests which can be used to identify COVID-19 in a patient. In a PCR test, sample is taken from a throat swab and tested to detect the virus’ RNA genetic code. Antigen testing tests for the proteins on the outer layer of the viral membrane using antibodies.
- 2 phase diease
- Phase 1=transmission
- Phase 2=host immune response (varies according to the person)
- Infects cells by binding to cell surface protein angiotensin-converting enzyme 2 (ACE2) through receptor binding domain (RBD) of the spike protein
- Enters the cell through endocytosis and then releases genetic material
- RNA finds the ribosomes in the host cell which turns the RNA into proteins, allowing the virus to take over the cell
- At end of life cycle, sends proteins to new cells so that more virus particles are made (exocytosis)
- Jump from animal to human
A helpful video describing the life cycle of COVID-19:
Direct transmission via particles in the air or on surfaces
- COVID-19 is a zoonotic virus which jumped from animal to human but is now specialized to humans
- There is still much unknown about who gets COVID and to what extent they will show symptoms, but ultimately respiratory transmission is the dominant form of transmission
- People with a weakened immune system or other conditions such as lung disease, obesity, advanced age, and heart disease are more likely to contract COVID
- If the host is symptomatic, the concentration of SARS-CoV-2 RNA in the upper respiratory system declines after symptoms begin, meaning they are less contagious
- Hosts are not contagious anymore after about 6 days of being infected.
COVID-19 is affecting people world wide. Visit The WHO Coronavirus Dashboard to see the most updated distribution of the virus.