COVID-19 variants: Why they happen and what we can do about them

If there has been one universally unwelcome interloper across the country and the Pacific Northwest this summer, it has been the delta variant. This highly contagious form of the virus that causes COVID-19 has become the dominant variant in Washington state, driving record numbers of infections and hospitalizations. It’s fair to wonder how this situation will end.

Delta isn’t the first COVID-19 variant — will it be the last or are other variants likely to pop up? If so, is there anything we can do to stop them?

What viruses do

To answer those questions, it helps to know a little bit about virus behavior. Viruses may be simplistic, but they are proficient at their mission: invade and duplicate. Viruses infect living organisms (people, for example), enter an organism’s cells and then make copies of themselves, copies that then go on to infect other organisms — and so the process continues.

Sometimes these virus copies are not exact replicas of the original; small changes (or mutations) in the virus’s genetic material are introduced during the replication process, and voila — a variant is born.

“Coronaviruses are notorious for how quickly they mutate,” says Mike Myint, MD, an infectious disease specialist and epidemiologist with MultiCare. “These viruses can jump back and forth between animals and people, accumulating a lot of changes. Sometimes these changes can make a variant more successful at infecting people, giving it a biological advantage, so that variant will outcompete less infectious variants.”

It was this process that led to the rise of delta. “We anticipated there would be COVID-19 variants” says Mary Fairchok, MD, a pediatric infectious disease specialist at Mary Bridge Children’s. “But no one could predict the rate at which they would emerge, how infectious they would be and if we could stay ahead of them through masking, vaccination or other measures.”

Where we go from here

While outrunning the virus’s ability to produce dangerous new variants isn’t easy, that doesn’t mean we are powerless. It is possible to slow down the rate at which these new variants appear; the key is implementing measures that keep the virus from being able to spread quickly and widely: masking, social distancing and perhaps most importantly: vaccination.

“If enough people in a population are immune to the virus, it can never really set up shop in people’s bodies, and if it can’t set up shop, it doesn’t have the opportunity to mutate,” says Dr. Fairchok.

The ideal way to prevent the virus from mutating is through vaccination. Why?

One reason is that vaccination is effective at stopping COVID-19 infection: In the United States, says Dr. Fairchok, fully immunized people are two and a half times less likely to get infected than unimmunized people.

Another reason is that while people who are vaccinated can still get COVID-19, they tend to be contagious for a much shorter amount of time than someone with COVID-19 who is not vaccinated.

“The less contagious you are, the fewer virus particles you are shedding into the community that can cause new infections,” says Dr. Fairchok. “Less virus circulation means fewer chances for the virus to mutate and produce variants.”

Vaccination is also the safest way to build immunity.

“People who are vaccinated have much lower rates of hospitalization and death if they catch COVID-19, than those who are unvaccinated,” says Dr. Myint. In Washington state, more than 90 percent of all deaths and hospitalizations from COVID-19 are in those 12 years of age and older who are not vaccinated, reports the Department of Health.

The end of the pandemic has yet to be written. To some extent, how this situation plays out is in our hands. The sooner we all choose to vaccinate and withhold opportunities for the virus to mutate, the sooner the pandemic fades — the sooner COVID-19 becomes an illness that we live with, like the flu, rather than one that upends lives. If vaccination rates remain stagnant, it’s possible that we will continue to see wave after wave of variants.

“We should all be doing our part to reduce the spread of COVID-19,” says Dr. Fairchok, “And the most important thing you can do, if you are able, is to get vaccinated.”