If a virus isn’t considered ‘living’ — then what exactly is it?

by | Sep 15, 2020 | health & nutrition | 0 comments

answering the question that my science teacher failed to answer properly

**disclaimer: No. This isn’t another coronavirus piece. This is something different. It’s a researched piece about viruses in general to answer some questions I had way back since early 2000s. Sources are included as links in the text. And no, I don’t actually believe they’re miniature aliens.**

I remember back in high school, my science teacher at the time announced that a virus isn’t considered a living thing. It didn’t fit in with the requirements of life as dictated by MRS GREN — the seven traits that qualify something as being ‘alive’.

She argued that a rock wasn’t alive because it didn’t move, that the pieces of paper we were scribbling our useless notes on couldn’t reproduce. But bacteria counted because it had all the seven traits: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion and Nutrition

I remember putting my hand up, being that one kid that always asks the annoying questions. “What about viruses?”

She told me they didn’t count. I pressed further for an answer. If it wasn’t alive, what are they? Are they machines? Are they aliens? Are they miniature biological computers made by aliens?

My teacher probably thought I was trying to create a conspiracy theory. She almost gave me detention for asking questions she couldn’t easily answer. I just had to accept it for what it was — that viruses aren’t considered alive, just like the rocks outside.

So what exactly is a virus?

I wasn’t allowed to write aliens in the exams. The correct answer, according to my high school science teacher, is a piece of RNA or DNA with a protein coat that floats around messing with people’s health. This, of course, is paraphrased.

I can’t remember what exactly I wrote, only that I got the mark I needed to pass.

What exactly is a virus?

The idea that they’re part alien stuck with me out of amusement. I would always tell people, with a reference to the aliens’ meme guy, that if a virus isn’t considered alive, then it certainly must be extra-terrestrial.

It didn’t help that pictures of viruses often look like something out of an alien movie, with their prongs and pods.

Because aliens just felt like a better classification for viruses than a non-living relative of rocks. What my high school science teacher failed to mention is that MRS GREN isn’t always a hard and fast rule when it comes to biology. What can be considered living is actually a lot fuzzier than what we’re taught. The famous MRS GREN just makes testing high school kids easier and more clean-cut that a full-blown discussion on what we can consider as ‘alive’.

It turns out that viruses don’t fit the ‘living’ definition because it doesn’t have its own biological machinery to replicate. It requires a host, using it as a shell to create copies of its genetic code. Replication is more like a process of photocopying itself by using the resources its host has to offer. It doesn’t divide in the same way cells do, but instead manufactures and reassembles its host into the required viral components.

In a way, the need for a host makes it sound like a parasite — except it’s not. The major difference between living parasites and viruses is that a living parasite consumes energy. There is some sort of metabolic process that keeps the organism ticking. Without it, the organism dies.

A virus, however, doesn’t need energy to survive. It has no metabolic process and, in theory, can float around indefinitely until it finds itself a host and creates more copies of itself.

In a way, it’s more like a bio-chemical based machine that only works when it’s ‘plugged in’ on a host than an actual parasite.

So is it alive?

The technical answer is no. The real answer is debatable based on how far can we go to classify something as ‘life’

The grey area between living and non-living

Unfortunately, viruses aren’t aliens, despite being an excellent candidate for conspiracy theorists. They’re biochemical organisms that sit in the gray area of living and non-living.

According to the December 2004 issue of Scientific American, viruses evolved from being classified as a ‘poison’ to ‘biological chemicals’.

For a long time, viruses were placed in the same family as bacteria but got demoted to inert chemicals in 1935 by Wendell M. Stanley, a researcher, academic and eventual Nobel prize winner, at the Rockefeller University in New York City. He figured out how to crystallize a virus and saw that it was just a package of complex biochemicals. There was no actual biochemical activity required for its continued existence. He found that a virus is just nucleic acids (DNA or RNA), which is a genetic blueprint for organisms enclosed inside a protein coat.

When a virus enters a cell — the host — it sheds its protein coat, takes over the cell, and rearranges the host’s genetic material to manufacture copies of the virus’ DNA or RNA. It wraps up the newly assembled viral bits together and leaves the cell to go and infect more cells. The process usually kills off the host, or mutates it based on exchange of RNA or DNA information between the virus and the host. This sometimes happens because a virus replication process is a biochemical act of breaking apart genetic blueprints to create new ones. Whatever remains either form into something that may be enough to keep the host alive, or a trail of genetic junk and destruction that ceases to be MRS GREN, check all the obvious boxes, worthy kind of being alive.

HPV and hepatitis are examples of transformative viruses that doesn’t kill its host but create unfavorable outcomes for the host it transforms. The host cell itself doesn’t die from the processes instigated by the virus but continues its existence in a limited capacity. Issues arise when these transformed cells replicate to form cancers and tumors.

This process blurs the line between chemical reactions and life. A virus contains DNA or RNA, which is considered a blueprint for life but doesn’t use it in a way that can be neatly categorized as such. Stanley argues that viruses are more like an intelligent biological-based chemistry set. The chemical availability of a host activates the virus and its replication processes. The way viruses work puts them in the category of “nonliving parasites of living metabolic systems”.

Not all viruses are bad

Most of the time, a virus is presented as a destructive force for whatever it infects. It destroys the host by taking parts of the host and rearranging it into Frankenstein versions of itself. It chops and changes what’s available and leaves behind what it doesn’t need. Whether the host survives or not, and what it turns into is a different story.

One of these stories can actually result in a happy ending for the host. According to the Annual Review of Virology, September 2017 edition, viruses can act as tools in gene therapy for cancer patients. Viruses are being uses as an apparatus to deliver targeted cells and restore the function of defective genes present in replicating cells. According to the paper:

in hundreds of ongoing clinical trials, the most commonly used vectors for gene therapy are adenoviruses, retroviruses/lentiviruses, and adeno-associated viruses (AAVs)….These viruses offer the potential to cure cancer, correct genetic disorders, or fight pathogenic viral infections.

In a study by the American Society for Microbiology, April 2015, studies show that norovirus helps develop the intestine and immune system of mice after normal and healthy gut bacteria have been decimated by antibiotics.

In fact, it turns out that gastrointestinal tracts of mammals are covered in viruses, as much as they are covered in bacteria. The diversity of their existence suggests that they have important functions. For example, there is a type of virus in our guts called phages that keeps certain bacterial genes that are involved with digestion in check.

Beneficial viruses are also not limited to mammals. At Yellowstone National Park, the tropical panic grasses are in symbiosis with a fungus that is infected by the beneficial virus, allowing the plants to survive and thrive in soils that are more than 122 degrees Fahrenheit (50 degrees Celsius). For context, the ideal soil temperature for most plants are 65 to 75 F. (18–24 C.)

Laboratory controlled tests have recreated this same symbiosis between virus, fungus, and plant, allowing for plant to survive in elevated soil temperatures where it would have otherwise died.

There’s more to viruses than what the media is presenting to us and what we’re taught at school. It’s an entire scientific discipline that’s watered down for the general population to understand.

This brings me back to the original question — if a virus isn’t considered ‘living’, then what exactly is it?

For the conspiracy theorist, I’d still say aliens.

For the scientifically curious, a biological-based chemical that’s simple in physical structure but complex in their impact and relationships with the things they encounter.

Read more…