Infection
Source
Initially thought to have originated from Wuhan, China, the origins of this virus have recently grown ambiguous. Researchers believe that the virus started months earlier than first proposed (September 13, 2019 as opposed to December 1, 2019) and in a different location. This information is based on the amount of mutation that already occurred in the virus and the lack of bats in the Wuhan marketplaces.
Spread
The SARS-CoV-2 originated from bats, likely used an intermediate animal (once thought to be the pangolin, but likely not the case), and jumped to humans. Although the pandemic epicenter has been Wuhei, China, researchers believe that the first infection occurred elsewhere nearby, though this origin point is still unknown.
Initially thought to have originated from Wuhan, China, the origins of this virus have recently grown ambiguous. Researchers believe that the virus started months earlier than first proposed (September 13, 2019 as opposed to December 1, 2019) and in a different location. This information is based on the amount of mutation that already occurred in the virus and the lack of bats in the Wuhan marketplaces.
Structure
The SARS-CoV-2 has the following four main components:
- Nucleocapsid - genetic core
- Envelope/Membrane - surround nucleocapsid as protection
- Spikes - allow for cell entry and inspired name (crown --> corona)
Molecular Processes
Generally, viruses enter and exploit host cells to produce viral copies.
The SARS virus is no different. After entering the body, it primarily targets the lower respiratory tract, in which it hijacks lung cells.
Specifically, the SARS virus uses its spike proteins (mentioned in the Structure section) to bind with a cell receptor protein known as ACE2 and enter the cell.
Additionally, the SARS virus uses accessory proteins to evade immune responses, though the exact purpose of these proteins remains ambiguous. This ambiguity stems from studies that indicate that removing these proteins doesn't prevent immune response evasion, but makes the virus less pathogenic.
