What Is a Virus, Anyway?

Q:Coronavirus, treatments, vaccines . . . I’m confused! Can you please explain what a virus is, how it causes problems in the body, and how we fight it?

A:Many people have the same questions. These issues can be very confusing. Because we have limited space, let’s deal with the first parts of your question now and the rest in a later column.

Viruses, the most abundant known biological entities on our planet, are uniquely organized packages of chemicals that become biologically active only when they borrow or steal the “life machinery” of a living cell. Most viruses stealthily gain entrance into human cells and set up permanent residence there, incorporating themselves into the host cell’s diverse and complex internal environment. Such viruses may not cause overt disease, but they are the ultimate biological spies—parasites that blend in and appear to be “normal” features of the host’s internal landscape. In short, viruses are tricksters—stealthy, opportunistic invaders that sometimes are so disruptive that they cause disease and death.

There are two biochemical components of all known viruses: a set of genetic instructions and a protective outer protein shell. Some viruses have an additional layer, a greasy envelope or overcoat that helps to hide the identity of the sneaky invader.

The first component, the genetic material, gives at least two instructions: how to make and assemble proteins for its protective shell and how to make copies of its own genetic material. The second component, the protein shell, protects the virus’ genetic material from hostile chemicals, contains attachment sites for docking with living cells to gain entry, and provides the chemical “passkey” to penetrate the unsuspecting host cell’s outer membrane.

Viruses are generally classified by the kind of living creatures they infect (animals, plants, and bacteria), which kind of genetic material they contain, the size and shape of their shell, and whether they have an envelope. The whole family of coronaviruses are named because of their appearance under the microscope; the word “corona” means crown, and the spiked structures that surround them look like the virus is wearing a crown. Coronaviruses have a greasy envelope that we can exploit in our defense of their invasion: soapy water and sanitizing alcohol.

In the case of coronavirus, the virus hijacks the invaded cells’ normal factories so that they produce mainly proteins for the viral membrane envelope, spikes, and shell, as well as make multiple duplicates of the viral genetic material. Some kinds of viruses overwhelm the infected cells, and the process of exporting the millions of assembled viruses “pokes holes” in the host cells’ membranes. This kills the host cells—with no gratitude shown by the virus! Interestingly, in many cases the exiting virus weakens but does not destroy the host cells. The body’s own response to the invaders, the infected cells, and the surrounding tissues cause collateral damage that may lead to organ dysfunction. It is single vital organ failure or multiple-organ failure that produces fatal results.

But God has not left us unprotected and without hope—the Blessed Hope. You can count on that!

Peter N. Landless, a board-certified nuclear cardiologist, is director of the General Conference Health Ministries Department. Zeno L. Charles-Marcel, a board-certified internist, is an associate director of Adventist Health Ministries at the General Conference.