Pandemic Perspective #9 May 16 2020

Mutations: Hollywood vs. the real world

The term mutation has a negative, sometimes frightening connotation, especially when it appears in the popular media. Books and movies that describe worldwide pandemics triggered by a single mutation in a virus like Ebola, for example, do not reflect what happens in the biological world.

Genes are composed of thousands of elements and a tiny mistake in any one of these elements can affect how that gene influences some chemical event in a virus, a bacterium or a human. In the case of certain viruses such as the coronavirus group, these changes occur frequently but only a very few of these mistakes result in anything that matters. Specifically, a single mutation is very unlikely to transform a benign virus into a deadly one. It’s more likely that a mutation will be detrimental to the virus and that viral particle will not be able to propagate.

Redundancy is a characteristic feature of living things, including viruses that are not exactly “living” (they need another plant or animal in which to propagate). Traits such as ease of transmission and lethality require more than one gene for their evolution. The kind of single-gene disastrous events described in popular films such as Outbreak are exciting but as noted by one group of virologists, “baseless.”

A study that has only been released in pre-publication form, that is, it has not yet been peer-reviewed as of this writing, states that the SARS-CoV-19 virus has undergone several mutations, one of which has increased its transmissibility, the ability to spread from one person to another. They note that this trait does not also confer a greater risk of mortality.

If there is one word that characterizes this pandemic it is uncertainty. From the early dismal projections of mortality to the revelation that it can cause a serious and sometimes fatal heart complication in children, COVID-19 may turn out to give us deeper insights into how to respond to global pandemics