With a recent decline in new COVID-19 cases and the accelerated vaccine rollout to eligible individuals, people are seeing some light at the end of the tunnel and are increasingly beginning to ask, “When will things start to feel a little more normal?”
Clay Dunagan, MD, BJC senior vice president, chief clinical officer and infectious disease physician, recently shared his thoughts on herd immunity, the future of COVID-19 vaccines and life returning to normal — including his predictions for the upcoming St. Louis Cardinals baseball season:
What exactly is herd immunity and when do we expect our country to achieve it?
Herd immunity is when enough of a population is immune to a disease — that is, they’re no longer susceptible to it — that community spread stops. Said another way, it’s the point at which an infected person is unlikely to pass that illness on to others.
The percentage of a population that must be immune to establish herd immunity depends on how contagious the disease is. Because COVID-19 is so contagious, estimates are that as much as 80% to 85% of the population needs to be immune, either through vaccination or from having had the disease. So, it’s going to take us at least until late summer to get to these levels — and that’s assuming enough of the population decides to get vaccinated.
When do you think things might start to get back to being a little bit more normal? For example, do you think we will be able to attend Cardinals games this summer?
This is the question that everybody wants to know the answer to. I expect in the spring we’ll start to see the impact of immunity created through the vaccines and natural infections, coupled with warmer weather. However, a true return to normal will take longer. I don’t think we will be going to Cardinals games in person at the beginning of the season, at least not in large numbers. Getting there by the All-Star break would be a great accomplishment. Hopefully, we’ll be there in force in time for the play-offs and seeing the Cardinals in the World Series.
Are we expecting that COVID-19 is something we’ll always be dealing with in the future? And, do you think we will need to receive COVID-19 vaccinations on an annual basis, like we do for flu shots?
It’s hard to predict. The answer depends on whether and how fast the virus changes due to mutations and how long-lasting immunity from the disease or vaccine is.
By virtue of their make-up, coronaviruses don’t change their stripes as easily as the flu, which requires constant vigilance on our part to keep the vaccines aligned with the strains we’re seeing. But we know significant mutations can arise that could affect immunity, as well as transmission of the disease — and that might influence the way the vaccines work. There are some well-publicized variants in South Africa, the United Kingdom and other countries that are starting to appear in the U.S. While some of these variants appear to be even more contagious than the original strains, they aren’t necessarily more virulent. They do point to the potential need to modify the vaccine over time.
Fortunately, the early evidence is that the immunity produced by the vaccines, and at least some natural infections, looks to be pretty strong and durable. We won’t know about that for sure for some time, but I think there is reason to be optimistic that we will see long-lasting immunity. Nevertheless, researchers are busy working on strategies to boost current vaccines to help manage the threat of these variants.
There are so many rumors and so much incorrect information out there about the COVID-19 vaccines. Where do you recommend we direct our friends and family members who are looking for accurate information?
They can start with our own BJC website. It has a lot of good information, as well as links to other authoritative sites. The state websites, in both Missouri and Illinois, also offer good material and links to important sources of information. Finally, if people really want to dig into the details of the vaccine, they can visit the Centers for Disease Control and Prevention website or the U.S. Food and Drug Administration website.