What You Need to Know About COVID Variants With Prof. Dave Wessner

February 10, 2021

Author
Mark Johnson

We asked Dave Wessner, biology professor whose post-doctoral research focused on coronaviruses, to offer some insights on questions we’re hearing on campus about the COVID variants emerging around the world. 

COVID variants have been identified, not just in the United Kingdom, but in South Africa, Brazil and Los Angeles – all of which have spread around the globe. Will we see more of them?  (North Carolina’s state epidemiologist said last week that the British variant likely will gain a larger share of the infections in the state.)



It was almost a guarantee that one or more of these variants would appear in Davidson, and now we know that the U.K. variant was identified here. The South African variant has been detected in South Carolina and the U.K. variant has been detected elsewhere in Mecklenburg County. And the U.S. has not been aggressively sequencing viral isolates. So, if these variants have been identified with only minimal sequencing efforts, that suggests that these variants are more widespread. 

Are the variants more dangerous than the original strain? 



That depends on what you mean by more dangerous. The U.K. strain appears to be more transmissible than the original strain, but disease probably is not more severe (or not significantly more severe). Of course, if it’s more transmissible, then more people will be sick, which will increase the burden on healthcare facilities. That’s a danger. The same is true for the South African variant. It appears to be more transmissible, but probably does not cause a more severe disease. And, the question of vaccine efficacy needs to be considered. If the vaccines are less effective against these variants, then that is another measure of danger.

Are they more easily transmitted?



Most likely, yes. There have not yet been good studies measuring the transmissibility of these variants, but observations suggest the U.K., South African, and Brazil strains are more transmissible. In the U.K., the prevalence of variant B.1.1.7 increased rapidly during the last couple months of 2020. That suggests it spreads more rapidly than the earlier strain. It’s worth noting, though, that basic non-pharmaceutical interventions—wearing a mask, remaining physically distant, washing your hands—continue to work. Although these variants may be more transmissible, the mode of transmission has not changed.

The head of the World Health Organization on Monday expressed concern over news that vaccines might not be as effective against the variants. The same day, the Associated Press reported that people who have had COVID-19 could get re-infected by the variants. How will we ever get this disease under control?



The vaccines do seem to be less effective against these variants. But there are at least two pieces of good news. First, “less effective” does not mean ineffective. The Moderna and Pfizer vaccines are highly effective against the original strain of SARS-CoV-2. So, even though these vaccines are less effective against the new variants, they still will provide some protection. We should remember that the annual influenza vaccine often is only 60-70% effective. The two SARS-CoV-2 vaccines now in use were starting at 95% effectiveness. Second, these vaccines should be pretty easy to redesign to match new variants. Moderna already has plans to test the effects of a third booster shot and/or a vaccine designed specifically for the South African variant. 

There have been documented cases of reinfection throughout the pandemic. With the variants, it does seem that reinfection may become more common. The Brazil variant seems to be the most troubling. It’s been reported that a majority of people in Manaus, Brazil were infected in the spring of 2020. Yet, there has been a big wave of infections recently. One explanation is that people are being reinfected by the variant.

Again, it depends on what you mean by “under control.” Most experts agree that SARS-CoV-2 won’t go away. It probably will become endemic, a commonly occurring infectious disease that we need to deal with, like the four other coronaviruses that regularly infect us or influenza virus. Some infectious disease experts have predicted that, over the course of many years, it will become a virus that people get several times as children, providing them with enough immunity that they rarely experience severe disease upon infection as adults. But the immediate issue is slowing down the spread now, through vaccinations and mitigations efforts.

Do you have some encouraging news? 

The progress we’ve made has been extraordinary. We should remember that the first reports of this new disease occurred at the end of December 2019. Now, roughly a year later, we have several very promising vaccines. Yes, the loss of life and human suffering has been tragic; we should never forget that. But the scientific progress really has been remarkable.

Related Topics

Faculty