Virus Facts You Need to Know
We’re inundated with news about COVID-19 and other viruses, but how much do you really know about how they work and whom they target?
We’re inundated with news about COVID-19 and other viruses. How can you really protect yourself? By Charlotte hilton andersen
There’s a long-standing argument in scientific circles over how to classify viruses. They’re not inanimate, because they multiply, have genes, and evolve. Yet they’re not “alive,” as they don’t have cells, can’t convert food into energy, and can’t survive on their own. Viruses are biological zombies. They have one mission: to find a host and use it to replicate. They reproduce by hijacking the host’s cells, eventually causing them to burst and die. That’s why viruses that infect humans nearly always cause illness. Fortunately, just as we know a great deal about how viruses do their damage, so do we know how to fend them off. These facts are a good place to start.
1 There are many more viruses than you think
We often think of just a few viruses—influenza, HIV, and now coronaviruses—but they are the most plentiful microbes on the planet. There are about 320,000 types that infect mammals, but just 219 are known to infect humans, according to the U.S. National Library of Medicine.
2 They are even in the rain
The next time you dance in the rain or catch snowflakes on your tongue, you might want to consider the fact that it’s literally raining viruses. Viruses and other microorganisms get swept up into the atmosphere in small particles from soil and sea spray, returning to the earth via rain, snow, and sandstorms, according to a study published in Nature. Luckily, most of them aren’t infectious.
3 Figuring out how contagious they are is both an art and a science
One way to measure viral spread is R0 (pronounced “r naught”), which is the average of how many people may be infected by a single person with the virus. If the R0 is 4, then each infected