The intruder stalks his prey with stealth and precision, preparing to pierce the armor of his quarry. Once inside, the aggressor forces its host to produce more invaders, then explodes it, spewing out a large number of invaders that can continue their rampage on a larger scale.
The drama, depicted in a microscopic video of SARS-CoV-2 infecting bat brain cells, paints a picture of how the pathogen turns cells into virus-making factories before the host cell dies.
The video was produced by Sophie-Marie Aicher and Delphine Planas, virologists from the Pasteur Institute in Paris, who won an honorable mention in a microscopic video competition sponsored by Nikon, the photo company.
Filmed over 48 hours with an image recorded every 10 minutes, the footage shows the coronavirus as red spots circulating among a mass of gray blobs — the bat’s brain cells. After being infected, the bat’s cells begin to fuse with adjacent cells. At some point, the entire mass bursts, resulting in the death of the cells.
Ms Aicher, who specializes in zoonotic diseases — diseases that can be passed from animals to humans — said this contagious juggernaut was the same in bats and humans, with one key distinction: bats don’t get sick in the end.
In humans, the coronavirus can evade detection and cause more damage, in part by preventing infected cells from alerting the immune system to the presence of the invaders. But its special power is its ability to force host cells to fuse with neighboring cells, a process known as syncytia that allows the coronavirus to go undetected as it replicates.
“Every time the virus has to leave the cell, it runs the risk of being detected, so if it can go directly from one cell to another, it can work much faster,” Ms Aicher said.
She said she hoped the video would help demystify the virus and make it easier for people to understand and appreciate this rogue nemesis who has turned billions of lives upside down.
“It’s important to help people get beyond the scientific jargon to understand that this is a very advanced and smart virus that is well adapted to make people sick,” she said.