Saturday, May 16, 2020

The Case for Microbe Parasites

Lately anyone who makes a positive case for viruses may be looked upon with suspicion. In the case of one specific coronavirus, COVID-19, that view is understandable. The novel disease is devastating and unpredictable. All viruses are considered ‘obligate’ parasites, growing only in association with their hosts, completely dependent on invading the living cells of their hosts.

We recall two virus-related events with more positive effects than the recent COVID-19 phenomenon. When I first entered the teaching profession, a veteran public-spirited teacher in my building initiated several campaigns. One of her memorable projects was a crusade against the invasive gypsy moth scourge. These pests had been accidentally introduced to New England from Europe in 1868. Eventually they became rampant all over the Eastern US. Government agencies still attempt to control the widespread gypsy moth infestation in the US. A virus known as NPV was one natural control agent introduced into defoliated forests. This virus controls harmful insect infestations. My colleague studied the gypsy moth life cycle and contributed her knowledge and energy to a ‘natural’ virus control campaign in our Northern New Jersey neighborhood in the 1960s.

Observing the action championed by my teaching colleague was a personally impactful introduction to the intricacies of ecology. What does ‘native’ mean with respect to our iconic eastern oak species, the preferred nutrition of the gypsy moth? And how did the ‘invasive’ gypsy moth insect species become suddenly destructive in America, but not nearly so destructive in their original European habitat?  

Another memory in personal family lore is the hike my daughter and I shared on the Mount Tammany Trail in the heart of the Delaware Water Gap National Recreation Area in the summer of 1989. One of the periodic gypsy moth outbreaks occurred then. The moth infestation was distressing, even on the scenic trail up Mt. Tammany. But the view from the top looking down on the famous Delaware Water Gap was unforgettable. Memories of my colleague several decades before and the hazards of exotic and invasive species are still poignant.

One control for gypsy moths, specifically, is a naturally occurring virus called NPV (nucleopolyhedrovirus). NPV virus substances can be industrially produced as a bio-pesticide to help control insect scourges. There are other natural controls acting against nuisance organisms including bacterial and fungal remedies.

Parasitic viruses to control other harmful organisms? Yes, many viruses are beneficial. Harmful planetary life forms would be uncontrollable without an abundance of different viruses. For example, without viruses called bacteriophages, many harmful bacteria would multiply and occupy every conceivable niche on Earth. We challenge readers to research the benefits of viruses. The same may be said for bacteria, most of which are benign or helpful. We live in a fascinating world of legions of microbes. 

Without atmospheric viruses and bacterial fragments, no raindrops or snowflakes would have a nucleus around which to form. Viral and bacterial fragments are carbonaceous and ultimately become recycled material for bottom dwelling sea life. Over eons this material is returned to the atmosphere in the form of needed nutrients to maintain the life sustaining carbon cycle. Readers may want to review our post on the carbon cycle:

Viruses and bacteria both contribute in various ways to a robust and healthy planetary home for humanity. These contributions are both historic and current. Historically, ancient bacteria are the origin of many of today’s plethora of mineral resources. Viruses and bacteria have sometimes acquired a negative reputation. In God’s created order, we must search deeply to discover multidimensional truth. Each exists for a purpose in our created world—God’s purpose.     

With a nod to the purpose for bacteria, readers may wish to review another past post:

Dr. Hugh Ross, president of Reasons to Believe has written voluminously on the wonders of God’s created world. We close with two passages from his blog post of 3-30-20, Viruses and God’s Good Designs:”

“Life forms on Earth larger and more complex than microbes would be impossible without an abundance of viruses. Without viruses, bacteria would multiply, and, within a relatively short time period, occupy every nook and cranny on Earth’ surface. The planet would become a giant, bacterial slime ball. Those sextillions of bacteria would consume all the resources essential for life and die.

“Viruses keep Earth’s bacterial population in check. They break up and kill bacteria at the just-right rates and in the just-right locations so as to maintain a population and diversity of bacteria that is optimal for both the bacteria and for all the other life forms. It is important to note that all multicellular life depends on bacteria being present at the optimal population level and optimal diversity. We wouldn’t be here without viruses!”