When a farmer sprays his field with insecticide to protect his crops, he unwittingly becomes a tool for natural selection. He kills the overwhelming majority of the targeted insects, leaving behind only the individuals which were born with the randomly mutated propensity to be slightly more resistant to the insecticide than their ill-fated brethren. These individuals reproduce to refill the population, in the process strengthening their resistance and forcing the farmer back to the chemical companies once again for new insecticides. This is but one example of evolution that happens all around us, every day.
Another example, and even more problematic, is humankind’s constant arms race against bacteria. Modern medicine has given us a practical miracle in the form of antibiotics to battle bacterial infection, but as incredible as this boon has been, it is far from perfect. Because in part of the incredibly high reproductive rates of most bacterium, and also because of their overwhelming ubiquitousness in our lives, these tiny creatures evolve at an astounding rate, mutating resistances to our “miracle drugs” nearly as fast as we can make new ones. Recently examples have been found in the soil of (so far benign) bacteria which actually eat antibiotics.
Before we discovered antibiotics, people had begun using bacteriophages against infection. A bacteriophage, or phage for short, is a virus that specifically target and destroy bacteria. While these were occasionally wildly successful, just as frequently they were completely ineffective. At the time, no one knew how to tell when a treatment was going to work or not, and when the much more reliable antibiotics were developed phage therapy was all but forgotten.*
Enter the burgeoning new science of genetics. It has been observed that bacteriophages are the most prolific form of life** on the planet, living anywhere on the world capable of sustaining bacteria. Careful looks at these viruses revealed wild divergence and variety in their makeup, and continued study showed that each phage seemed tailored specifically to a particular bacteria. Since this discovery, scientists have been wasting little time cataloging types of phages and pairing them off with their respective targets.
This new stage of phage therapy has some dramatic improvements over the antibiotic approach. First, unlike the broad-spectrum antibiotics, phage therapies kill only the specifically targeted bacteria, leaving beneficial bacteria completely unmolested. Second, there is no impact on the immune system, making the treatment safe for transplant patients and others with intentionally suppressed immune systems. For that matter, there is no known effect on the well-being of the recipient other than being cured of the targeted infection. In other words, no side effects. Phages can be injected, ingested, or freeze-dried and taken as pills with equal effectiveness. Also, and the thing I think is most amazing, is that while bacterium do evolve means to elude or fend off phages, phages evolve the means to overcome bacterial tricks with equal rapidity! Instead of spending hundreds of millions of dollars and countless man-hours desperately trying to outsmart a bacteria, we can instead sit back (relatively speaking) and let evolution do the work for us!
The FDA has approved phages for use on all foods and has given them the GRAS qualification. (Generally Recognized as Safe) Additionally, a phage cocktail to combat Listeria monocytogenes and other bacteria which cause food poisoning has been green-lighted for periodic updates to its patent, allowing for the holder to continue to account for the evolution of both the bacteria and phages into perpetuity.
In all, this is a discovery… or a refinement of a discovery at any rate… with incredible potential for good in the world. Understanding what evolution is and how it works, and using that knowledge, pushes back against human suffering in ways we have yet to begin to appreciate. Elimination of cancer, bacterial disease, germ warfare, food spoilage, wound infection… the list of possible uses are mind boggling. The advances in sanitation alone, treating hospital clothes and surfaces, tools and instruments can save unnumbered lives and misery.
Sign me up for that.
*Except in parts of Russia, Georgia, and Poland
**Leaving aside the legitimate (though esoteric and largely pointless) debate on whether or not viruses actually represent “life.”