UK Experts Tackle Delta Variant Questions

LEXINGTON, Ky. (July 19, 2021) — As the SARS-CoV-2 delta variant continues to spread across the United States and hospitals’ COVID-positive intake numbers climb again, many questions remain around both vaccine effectiveness and vaccination rates, and what these numbers could mean moving into the fall.

Recently, a small panel of experts across the University of Kentucky and UK HealthCare participated in a discussion on these issues and what they mean for Kentucky. Becky Dutch, Ph.D., a virologist and the vice dean for research with the UK College of MedicineVince Venditto, Ph.D., an assistant professor of pharmaceutical sciences in the UK College of PharmacyDr. Ashley Montgomery-Yates, UK HealthCare chief medical officer for inpatient and emergency services; and Dr. Aaron Grubbs, an infectious disease physician and UK HealthCare assistant medical director of infection prevention and control, are among the experts across various specialties at UK who are closely following the latest data trends.

Dutch has spent almost three decades of research understanding the molecular mechanisms for how viruses work. Much of her work at UK is focused on RNA viruses that infect the respiratory tract. She said it is not surprising that variants have come out of the SARS-CoV-2 virus.

“When viruses replicate, they make billions and billions of copies of themselves and every time they make a copy, they can make mistakes,” she said. “Over time, you will expect that normal viral evolution means you are going to start picking up variants.”

So far, Venditto, who has extensive background in vaccine design and immunology, said that while evidence is evolving with regard to the delta variant, the COVID vaccines are doing what they are supposed to do against it so far.

“The vast majority of the people who are going to the hospitals right now with COVID infections are not vaccinated,” he said. “This is evidence that the vaccines are working. They are inducing the appropriate immune response to keep us protected, keep us out of the hospital and prevent death.”

As we look to the fall, do you expect to see another surge of hospitalizations if the vaccination rate in Kentucky does not increase?

Montgomery-Yates: The issue is not that the Delta variant is a more aggressive virus, it is just more transmissible, which makes it easier to catch. Last year, we had all of the statewide mandates in place to protect us – everybody wore a mask, nobody was going out in mass numbers, everything was shut down. Now that we have released all of those measures, those working in the health care industry fear that there is going to be a large gathering of some sort, and somebody is going to be sick, and we are going to have a big surge again. It does not take very long.

Last year, even the people who were not necessarily full believers in what the Centers for Disease Control and Prevention (CDC) was saying, I think there were things in place that kept them safe in ways they did not even realize and that is all gone now. I think we are fearful that those places where the vaccine rates are lower are going to see problems.

When it comes to younger people, specifically children, is it still reasonable for parents to say that they do not have enough data on how the vaccines may affect their kids?

Grubbs: There is data down to 12 years old to suggest that the vaccine is safe. There have been many, many people who have been exposed to this vaccine and relatively few serious adverse effects from it. I think that there is good safety in children in that age range. The studies are still going on in children who are younger than 12, so we will have to wait and see.

Will there be a need for a COVID vaccine booster this fall or winter?

Dutch: I think that option is being discussed and kept open because things continue to change. Delta will not be the last variant. The more people who get it and have it replicating in their system, the more variants we will see over time. At the moment, your vaccines are doing a really good job against delta, so I am not concerned that you need a boost because of delta.

Grubbs: Even if there is a booster, it would probably be recommended for particular populations first, as opposed to broadly. We do know that in some populations, vaccine response is not as good, so those patients might benefit from a boost before younger, healthier populations would.

Should vaccinated people start wearing masks again? And, if the number of cases in Kentucky continue to rise, do you anticipate a reinstated mask mandate?

Dutch: The evidence suggests that a vaccinated person can get the delta variant, but they tend to have relatively mild infections. Having said that, if I was going to spend a lot of time in a really, really crowded room right now and this keeps getting worse, I might consider it simply to decrease my chance that I might pick up the delta variant and spread it.

Venditto: I think it also depends on your particular situation and the people who are around you. The Pfizer vaccine, for example, is 96% effective at preventing hospitalization. If you are vaccinated, you may still get sick, but you likely will not be hospitalized, but if you have children or people who are immune-compromised in your house, then you may still consider wearing a mask because it is going to protect your loved ones. Personally, I am not wearing a mask outside generally, unless I am maybe in a stadium, or in a really closed-off space where I do not know everybody around me, and the risk of transmission is relatively high.

Montgomery-Yates: At UK HealthCare, we are all still wearing masks in any area where we are doing patient care or where we could run into a patient because there is still some risk, and we do not know which family members may be vaccinated or not, or who could be immune suppressed.