An animated look at how the novel coronavirus that causes COVID-19 enters the body and infects cells. Illustrated by a Scripps Research scientist, this installment of Science, Simplified gives an overview of the entire infection process.
Science, Simplified is a new series from Scripps Research highlighting key scientific concepts in short, easy-to-understand videos.
Video Script:
Due to its unique features, the novel coronavirus is particularly good at infecting new cells, both in the upper respiratory tract, as well as deeper down in the lungs. Here’s a look at how the process takes place.
1. The microscopic virus enters through the nose or mouth, where it begins its infection of our airways.
2. The outer spike protein of the coronavirus latches onto specific receptors on the surface of cells in our respiratory tract. In the case of COVID-19, the virus latches on to the ACE2 receptor.
3. This binding triggers the process by which the virus fuses into human cells. The viral envelope merges with the oily membrane of our own cells, allowing the virus to release its genetic material into the inside of the healthy cell.
4. The genetic blueprint of the virus is RNA (instead of DNA), which acts as a molecular message, instructing our host cell machinery to read the template and translate it into proteins that make up new virus particles.
5. The hijacking persists, as the human host cell continues to generate more copies of the virus, assemble these copies into viable particles and traffic them to the outer edges of the cell for release.
6. Each infected cell may produce and release millions of copies of the virus, which can then go on to infect other neighboring cells, as well as neighboring people when they are expelled from the airways in droplets via coughing and sneezing.