the original version of this story appeared in Quanta Magazine.
Since viruses came to light in the late 19th century, scientists have differentiated them from the rest of life. Viruses were much smaller than cells and carried little more than genes within their protein envelopes. They couldn’t grow, copy their own genes, or do much. The researchers assumed that each virus was a solitary particle wandering the world alone, capable of replicating only if it collided with the right cell that could absorb it.
This simplicity was what attracted many scientists to viruses in the first place, he said. Marco Vignuzzi, a virologist at the Infectious Diseases Laboratories of the Singapore Science, Research and Technology Agency. “We were trying to be reductionist.”
That reductionism paid off. Studies on viruses were crucial for the birth of modern biology. Lacking the complexity of cells, they revealed fundamental rules about how genes work. But viral reductionism came at a cost, Vignuzzi said: By assuming that viruses are simple, you blind yourself to the possibility that they could be complicated in ways you don’t yet know about.
For example, if we think of viruses as isolated packages of genes, it would be absurd to imagine them having a social life. But Vignuzzi and a new school of like-minded virologists don’t think it’s absurd at all. In recent decades, they have discovered some strange features of viruses that don’t make sense if viruses are solitary particles. Instead, they are discovering a wonderfully complex social world of viruses. These sociovirologists, as researchers sometimes call themselves, believe that viruses only make sense as members of a community.
It is true that the social life of viruses is not like that of other species. Viruses don’t post selfies on social media, volunteer at food banks, or commit identity theft like humans do. They do not fight with allies to dominate a troop like baboons; They do not collect nectar to feed their queen like bees; They do not even freeze forming slimy mats for their common defense as some bacteria do. However, sociovirologists believe that viruses do cheat, cooperate and interact in other ways with its fellow viruses.
The field of sociovirology is still young and small. The first conference dedicated to the social life of viruses took place in 2022, and the second will take place this June. A total of 50 people will attend. Still, sociovirologists maintain that the implications of their new field could be profound. Diseases like the flu make no sense if we think about viruses isolated from each other. And if we can decipher the social life of viruses, we could exploit it to fight the diseases that some of them create.
under our noses
Some of the most important evidence of the social life of viruses has been on display for almost a century. After the discovery of the influenza virus in the early 1930s, scientists discovered how to increase reserves of the virus by injecting it into a chicken egg and letting it multiply inside. Researchers could then use the new viruses to infect lab animals for research purposes or inject them into new eggs to continue growing new viruses.
In the late 1940s, Danish virologist Preben von Magnus was growing viruses when he noticed something strange. Many of the viruses produced in one egg failed to replicate when he injected them into another. In the third transmission cycle, only one in 10,000 viruses could still replicate. But in subsequent cycles, defective viruses became rarer and replicating ones recovered. Von Magnus suspected that viruses that could not replicate had not finished developing, so he called them “incomplete.”
