Coronavirus FAQ: Help me with omicron vocab. What's immune evasion? Epistasis?



The coronaviruses variant of concern known as omicron has a 3D-generated image. The little bumps are spikes.

The images are by Uma Shankar Sharma.

We answer frequently asked questions about life during the coronaviruses crisis. If you have a question you'd like us to consider for a future post, email us at goatsandsoda@npr.org You can find an archive of our FAQ here.

I feel like I need a medical degree when I read about the new omicron variant. What does "immune evasion" mean? Is it a virus neutralization test? Help!

Those without a medical degree can feel a little lost when they hear about COVID-19. We turned to three experts who were COVID-wise: Dr. Greg Poland, professor of medicine and infectious diseases at the Mayo Clinic in Rochester, Minn., and Matthew Binnicker, PhD.

Let's start with a quote from Weatherhead.

The omicron variant has a lot of genetic changes. Many of these changes are found in the spikeProtein region. Some of the individual mutations suggest that the omicron variant may be more resistant to the immune system. The clinical impact of omicron is unknown because of the phenomenon of epistasis.

Here's a guide to help you catch all of that.

A change in a virus's genetic code is called amutation. There are normal parts of viral replication. As a human is spread by a Viruses, they make copies of themselves. A mistake is made during copying. The behavior of the virus can be changed by a few small changes. Most of the time, they don't.

A variant is a version of the virus that has a slightly different genetic sequence because of the appearance of the mutations. As the virus spreads, many genes disappear. Sometimes, the virus's genetic makeup can be passed down to future generations. The virus can accumulate a unique set of changes that make it different from other versions. These versions are called variations.

The World Health Organization and the Centers for Disease Control and Prevention alert the public to variant of concern that could pose added risk because of increased transmissibility, increased severity of disease or decreased effectiveness of public health interventions.

The ability of a virus to spread is called transmissibility. The delta variant is more transmissible because of the fact that it is better at attaching to and infecting cells. We don't know if omicron is more transmissible than the highly transmissible delta variant.

Immune evasion is when your body produces an immunity to a disease after an exposure. Sometimes a virus can change in a way that helps it evade detection. Scientists call it "immune evasion." There's a chance that omicron could be better at immune evasion than the other versions because of the specific mutations on its spikeProtein.

If you score more points or get to the finish line first, you're the best. Winning in the world of viruses is like winning on a reality show; viruses can evolve to cause more harm than before, and become the No. 1 strain. Binnicker says it's survival of the fittest. Delta showed us it was the leader of the hill. We will have to see if omicron is better at transmitting than delta over the next two to four weeks. If it is, it will likely push delta out of many regions of the world and become the dominate variant.

The Greek word for standing upon is Epistasis. What does that mean about viruses? The term genetics describes how the genes affect each other. The way a virus behaves depends on what other genes are present. Scientists can't look at a single piece of information and know how it will change a virus. Any movement by one of them can affect the entire formation.

Let's take this apart. A test is an analyzation. Those who love science fiction are familiar with neutralization. You've won if you stop the alien ship from attacking. We want to know if the immune system can stop a virus. A lab test that measures the ability and magnitude of a human's antibodies to stop infections is called a VNA. The test can be used to determine how well one part of the immune system is working. It can be used to estimate how well a vaccine works.

If a person was exposed to the coronaviruses and received a vaccine at least six months later, they have hybrid immunity. This scenario causes high levels of antibodies and strong protection. Some scientists have called it super-immunity.

You've probably seen a lot of pictures of the virus. The spikes on the virus particle are created by the spike protein. It's a critical region of the virus for a number of reasons. The Spike proteins help the virus get inside the cells. The spike proteins are the target of many critical antibodies. The immune system can detect the virus by its spike proteins.

This isn't hard to figure out. Not enough is known to take much action to prevent infections besides getting vaccine and boosted, and we've relied on prevention strategies of masking and physical distance during the coronaviruses epidemic.

Eldred is a health journalist. She has written about COVID-19 for a number of publications. There is more at sheilaeldred.pressfolios.com. On social media, milepostmedia is on it.