An Imperfect Understanding of How Viruses Work

I just knew my younger daughter would be the best source of basic information for my science question.  She has a knack for explaining complicated concepts as if I were eight years old, and I never take offence.  It’s actually quite liberating, as I get to ask my questions in non-sciency ways.  Inevitably, she’ll have to rein me in whenever my imaginings stray too far into the realm of fantasy or I anthropomorphize just a wee bit too much, which is typical behavior on my part because it’s so fun to imagine life’s scientific mysteries that way.  

 

My burning question, this time, is, Why do viruses want to kill people; don’t they depend on them being alive to sustain the species?  Words like “host” and “natural selection” and “replication” don’t come to me easily.  Instead, my end of the conversation features imagery such as “stealthy shape-shifters”, “bullies”, “jackbooted soldiers sporting little mustaches that invite comment”.  

 

With my own middle child attitude of “can’t we all just get along?”, it really gets my goat that there are viruses (just like people) who eschew the mutually beneficial relationship and gains that symbiosis offers us.  The recent Delta variant of the Coronavirus bears special scrutiny here because it appears, in my mind, to be too greedy.  Its spear-brandishing conquest has proven to be scarily effective, but even worse, it is downright lethal.  My daughter happily assures me that it is not the design of the virus to kill off its host.  Well, “assures” is perhaps not the best way to capture the reality of what’s going on, nor to characterize how I respond. To prove her point, my daughter invokes the common cold as an exemplar of a virus that has perfected its game.  It can assure its longevity because it doesn’t kill its host, yet it can - with a desultory wave of the hand (or tendril) - easily replicate. Moreover, with its over-arching and innate desire(?) to guarantee survival of the species, the virus, at least collectively, must undergo the process of natural selection. . .  just as all species must.  After all, every species wants to be represented by the best and the brightest.  (Think Olympic athletes such as Simone Biles or Usain Bolt.)  It is likely that we have all, at one time or another or on many occasions, used the expression “survival of the fittest”, but we rarely take pause to consider any meaning beyond a metaphoric or pedestrian application.  

 

Every living organism is equipped with the ability to adapt or mutate.  We can be forgiven if we view mutation as something negative or undesirable.  After all, if we have spent an entire childhood calling younger brothers “mutants”, the reflexive association that we make tends toward the unpleasant or undesirable.  But mutation, just a more sciency way of connoting the more esoteric process of adaptation, is necessary for species survival.   We are, in fact, engineered for continuous adaptation.  

 

Consider the highly adaptive mosquito.  Entomologists who study mosquitos have long given up on the ideal of a mosquito-free world.  (And, really, it’s a dangerous ideal to exterminate an entire species.)  Once again, natural selection has assured that “the best and the brightest” will survive.  Decades of aggressive efforts to eradicate the most dangerous animal in the world through pesticides (such as DDT) failed to achieve this goal, but that doesn’t mean that mosquitos are completely dominating the game.  We should enjoy a measure of relief that scientists have broadened their thinking, and are coming up with very creative ways to reduce mosquito populations.  Listening to an NPR show about a month ago, I was amazed to learn that only about three species (out of some 3,000 different species of mosquitos) wreak all the disease havoc (Zika, West Nile, Yellow Fever, Dengue Fever, Malaria).  Because the field of genetics has exploded in recent years, we’re witnessing an exciting, creative surge.  The best ideas target specific species, the inherent value being that there is less chance of disrupting the balance of nature through unintended consequences.  One lab is engaged in a program whereby they breed male mosquitos that  transfer some type of toxic gene to their offspring, and the babies all die.  (A little bit sad, in a way; you gotta feel for those poor parents!). Another program targets sterility (and don’t ask me how, because all I can imagine is a row of white-coated lab technicians bent over their benches with scalpels as they perform vasectomies on male mosquitos who cry out in uncharacteristically high voices, “Please, you don’t have to do this!”) 

 

My daughter once again reins me in, and turns the conversation to viruses that, perhaps, haven’t been as successful in their adaptive behaviors.  If you remember, several years ago everyone was panicking about the SARS virus.  And then. . .  it just went away.  What did it fail to do, or how didn’t it adapt?  One of the most significant ways in which that virus differed from COVID-19, even though the two are closely related in other significant ways, was that transmission was more apt to happen if the infected person was symptomatic.  This makes a huge difference because contagious people could be isolated, and thus the disease could be contained and ultimately extinguished.  It wasn’t that SARS became dormant; it wasn’t that stupid or without options - it jumped to bats. . . and bided its time.  And, one thing I’ve learned - just recently - is that give a virus space and time and it will evolve, it will hone its skills.  So, in 2019, re-packaged as SARS-CoV-2, the virus jumped from bats back into humans.  Top management had ironed out the earlier deficiencies surrounding transmission, but the newer strain was not as deadly.  But, darn it, along comes the Delta variant, and it is proving to be even more highly transmissible. . . and even more deadly. . . AND it has apparently adopted a scornful, dismissive attitude toward the vaccinated, resulting in breakthrough cases.  (This new variant is expressing open dismay that it’s not enjoying attendant success if measured by how sick it can make vaccinated people.  You can bet the power brokers of the viral world are working on that shortfall, however.)

 

That, my friends, is how adaptation works, that is adaptation at the highest levels!  It would be wise not to underestimate those nefarious little evildoers.  In fact, we humans could do more in terms of our own (purposeful) adaptation.  So, stock up on bulk-size volumes of hand soap  and, of course, hand sanitizer (both very effective in destroying virus cells).  (I won’t even state the obvious about masks and social distancing, other than to. . . well, you can guess.)

 

Interesting facts and other asides about viruses. . . and breakdancing:

 

They cannot be grown artificially; I think this means that, in a way, they are parasitic - they need a live host cell to do their evil machinations.  

Adaptation:  humans take about 20 years (i.e., one generation), viruses take minutes.

Being a seamstress (or sewist, if you will), I can appreciate - when it comes to the sizing of individual viruses - the staggering aggregate suggested when it is stated that billions of insouciant individual viruses can launch into unrestrained break-dancing on the head of a pin without so much as tripping over the next individual virus, whose oxygen-enriched face is slightly scrunched up as it transitions from a head spin to a back flip, not for an instant risking a great tumble from the head of that pin.

Breakdancing will make its Olympic debut in 2024. 

A highly satisfying solution to mosquito attacks is “The Executioner”.  You can bat away at them and revel in the glorious sound of “zap” every time you connect.  (I have a dark side, people.)