By Bill Levesque
The novel coronavirus is doing what viruses do — in fact, what all life does. It’s mutating and creating new variants. This is evolution 101.
Much of the discussion about the coronavirus in recent weeks has been about the potential impact of these variants on COVID-19 vaccines now being administered worldwide. Just what does the future hold?
University of Florida Health virologist John Lednicky, Ph.D., a professor in the in the UF College of Public Health and Health Professions and a faculty member in the UF Emerging Pathogens Institute, talks about coronavirus variants and what they might mean for the pandemic.
Question: What is a virus variant?
Answer: What’s happened here is that different variants of the novel coronavirus have started evolving. Viruses constantly mutate. When they do, a piece of the virus’s genetic code changes. It’s a random change. Some variants develop mutations that end up making the virus less capable of replicating. And those virus strains typically go extinct. But some other mutations become worrisome. As with the novel coronavirus, they might make it easier for the virus to spread and become more contagious. They might mutate so that they’re better able to stick to human cells. Some strains become more virulent. The novel coronavirus accumulates two new mutations a month. That’s globally. So this is constantly happening.
Q: Do the novel coronavirus variants make it likely that our COVID-19 vaccinations will be less effective or won’t work?
A: Most predictions are the current vaccines will be effective at least against the variants that are here in the U.S., which includes the more contagious U.K. variant. The big concern is the South African variant. Recent reports indicate the Pfizer and Moderna vaccines are less effective against this variant. But right now, the South African variant is not predominant in the U.S. We have to be very careful not to get alarmed by reports of new research because there are so, so many reports that are being put out very quickly. There’s still a lot of what I call noise in the literature. Right now, we just don’t have a very good handle yet about what the big picture is. That will take time. We’re not very good predicting future events. I tell people to be less alarmist until we know more. The best thing right now is wear face masks, physically distance and certainly watch your hand hygiene.
Q: Do we face a future of ever more virulent variants of the novel coronavirus?
A: A virus doesn’t typically want to kill its host because if it does so, then it becomes extinct. Now what typically happens with other coronaviruses is that when they first show up in a human population, they cause problems and are more virulent. Then after a time, they attenuate, or get weaker. What’s probably going to happen over time with the novel coronavirus, especially as herd immunity builds up, is we’re going to get variants that have adapted specifically to humans. But they’ll become like the other common coronaviruses that affect us. They’ll become like a nuisance virus that we get every year. It’s not going to be as severe. We all hope that’s what’s going to happen. Even in my own work and research by other virologists, we’re beginning to see some mutations in the coronavirus genome that make them, we would predict, less fit. They don’t replicate as well. They take a little longer to produce virus particles. And oftentimes, those variants have been found in people with mild cases.
Q: But is there a level of unpredictability in how future variants will impact vaccines?
A: The complication of virology is that viruses are always changing. Assumptions that we make that work very well today might not work tomorrow as the virus changes. That’s why we have to stay on top of these variants. And the way to stay on top of it is to do frequent sequence analysis. If the South African version starts predominating in any part of the U.S., we can detect it right away and mitigate it.
Q: Should this talk about coronavirus variants dissuade people from getting a COVID-19 vaccination?
A: People should still definitely get vaccinated because, even assuming a variant makes a vaccine less effective, even partial protection can be extremely important. It still provides you with a level of protection. And that might be the difference between a severe and a mild form of COVID-19. The severity may be much lower.
Q: How does the novel coronavirus compare with other viruses in terms of how frequently it mutates?
A: The novel coronavirus is what is known as an RNA virus. The good thing about coronaviruses is, compared with other RNA viruses, their mutation rate is actually lower. Had this been another RNA virus, the number of variants would have been much, much, much, much higher.