What you need to know about the Delta Variant: University Health’s Dr. Jason Bowling answers your questions

The Delta variant is prevalent in San Antonio, Bowling says

SAN ANTONIO – Questions and concerns are surrounding a version of the coronavirus that is dominating infections in the United Kingdom and could become the dominating variant in the United States.

The Delta variant is responsible for 90% of all new COVID-19 infections in the UK, and 20% so far in the US, according to a report from The Associated Press. This new strain is more transmissible than the other variants and it could be more lethal.

Dr. Jason Bowling, with University Health, joins us to discuss the latest developments with the Delta variant and how the COVID-19 vaccines stand up against it.

You can watch the full interview in the video player above.

How prevalent has the Delta variant become in San Antonio?

“So in the San Antonio area, the Delta variant, it continues to increase. We are actually doing some sequence-based surveillance in a collaborative effort between UT Health and University Health to provide this information, the South Texas area. And in the most recent data analysis that ended from isolates June 1st, it was about 17% of the total number of isolates that was sent for surveillance. To put that in context, that fits in with what we’re seeing nationally. Most recent data from the CDC, their estimate is around 20% of variants of the United States are this new Delta variant. That’s up about twice what it was two weeks ago. So a significant increase in just the past two weeks. So we are seeing in San Antonio the same thing that’s being seen nationally,” said Dr. Jason Bowling.

What is involved in isolating variants?

“The 17% and the 20% estimates that are being provided are out of the isolates that are sequenced. Sequencing these viruses is a very specialized lab technique, until they take a sampling of all the viruses that are circulating. So not all the viruses that get tested when someone tests positive for COVID are tested, but a sampling of those is taken. And then out of that sampling, they look at what percentage are different variants. So out of the sampling that we’ve taken from the San Antonio area, we’ve seen it about 17% of this Delta variant, which again, is consistent with what we’re seeing on a national scale. This variant is increasing in number and is predicted to become the predominant variant in the next couple of months,” Bowling said.

How much worse is the Delta variant from other COVID-19 strains?

“The big concern about the Delta variant, in comparison to the prior variants and strains that have been identified before, is it appears more transmissible. So the existing predominant strain in the United States right now is this Alpha variant, which was formerly called the ‘UK variant,’ and it was about 40% more transmissible than the variant before it. The wild type strain, this Delta variant, is now 40 to 60% more transmissible than this Alpha variant. So this is the most transmissible variant or strain of the SARs-CoV-2 virus that causes COVID-19 that we’ve seen so far,” Bowling said.

What part of the population are we seeing hospitalized for COVID-19 now in early summer 2021?

“In early summer 2021, at this point in the pandemic, the most consistent trend that we see in people that are being hospitalized admitted for severe COVID-19 are people that are unvaccinated. It’s very uncommon for us to see somebody that is fully vaccinated to be admitted with COVID-19 at this point. And so, we’re seeing it across the age ranges now. Particularly, we are seeing some younger people because the younger age demographic are less likely to be vaccinated. If you look at the statistics, so we see some younger people being admitted with severe COVID-19, but older people that haven’t been vaccinated, certainly they’re at risk. And we’re seeing older people that are unvaccinated being admitted as well,” Bowling said.

How protective are the authorized vaccines against the Delta variant?

“This is information that we’re still learning -- how well do the authorized vaccines that we have in United States work against this Delta variant? We do have some information from the United Kingdom where the Delta variant now accounts for 95% of their isolates and they have the Pfizer vaccine and the AstraZeneca vaccine in the United Kingdom. So the Pfizer vaccine we have authorized here for use in the United States as well. The good news that is very reassuring is that the Pfizer vaccine is still 96% effective in preventing hospitalizations from COVID-19 disease when people are infected with a Delta variant. So we’re still seeing very good protection against kind of the worst case outcomes of hospitalization, severe disease with the Pfizer vaccine against this variant now. So it’s still important that people get vaccinated. Our vaccine, the Pfizer vaccine, still shows real world protection against this Delta variant,” Bowling said.

Can you get the Delta variant even if vaccinated?

“Even fully-vaccinated people can potentially get infected. The vaccine is not 100%, and when we look at the efficacy numbers, there’s the percentage that prevents any disease. Then there’s the percentage that protects against kind of mild or symptomatic disease and then severe disease and death. So no vaccine is 100%. But these vaccines are still pretty effective, highly effective against severe disease. Ninety six percent even against this Delta variant. But if someone that’s fully vaccinated that has a lot of ongoing exposure to other people that are infected, that really provides a lot of selective pressure that can put them at risk of getting infected. And so you don’t want to test how long that efficacy lasts for. The longer the exposure time period and the more infected, the higher viral load that someone has. It might be in the household. You really increase the chances that even a fully-vaccinated person could have one of these breakthrough infections,” Bowling said.

Is one shot of Pfizer or Moderna enough to protect me from Delta?

“We’re still getting information on this, but what we have seen and again, this is based on the UK experience, where they’re having a lot of issues with this Delta variant right now, one shot of the Pfizer vaccine does not seem to be providing very good protection against this Delta variant. We saw initially with the wild type strain before more of these more recent variants that one shot of the Pfizer and Moderna vaccines still had some decent protection. But as the virus has mutated and created these new variants of concern, we’re seeing that protection is not as good. So one dose of the vaccine, unfortunately, does not provide very good protection. It’s really important that people get both doses of the Pfizer or the Moderna vaccine. Any vaccine series that requires both doses, it’s important that people get both to get the full protection,” Bowling said.

When do we think a vaccine might be authorized for the under 12 age group?

“The under age 12 group is still at risk, right? They’re not currently eligible for the authorized vaccines. The good news is that Pfizer is doing a study right now on five to 11-year-olds. They anticipate those results will be available in September and they hope to get rapid expansion to include that group with the FDA shortly after the results are available. So September looks like the earliest timeframe we may see it. That’s great, because that’s right around when the school year starts. So hopefully we’ll see results then so that we can get this next age group included into the eligible vaccine group,” Bowling said.

What would you tell your family to explain how much more serious this is than a cold or the flu?

“When we compare COVID-19 to common colds and flu, one thing I want to say off the bat is that even with influenza, every year we see tens of thousands of deaths in the United States. And so, I wouldn’t minimize the impact that influenza can have. People can get very sick with the flu itself, particular people who are unvaccinated or have risk factors for complications. What we’re seeing with COVID, since it’s a newer pathogen, is there’s less preexisting immunity and people can get much sicker because they haven’t had prior exposure to it before, unlike people that have had a prior flu before and they get infected with flu again, they’re less likely to have a severe disease as they would if they were infected with COVID-19,” said Bowling.

How protected are you from the Delta variant if you have had COVID-19 but not been vaccinated?

“We are seeing now and we have learned that natural immunity, the antibodies that are provided, if you have a course of COVID infection, if you had COVID infection before, does not appear to provide the same level of protection against these new variants that we would hope for. So we know that because in the United Kingdom and in other countries as well, where this Delta variant is widespread, we are seeing people that have had prior infection with a preexisting strain, infections before this Delta variant was identified. These people are getting reinfected. Some of them are having mild infections, but there’s a wide spectrum and some are still having severe disease up to and including death. And so, we are seeing that natural immunity from prior strains of the virus does not provide very strong protection against this Delta variant. So, again, another message that we really need to get people fully vaccinated because we see that we have good protection with the full course of the vaccines,” Bowling said.

How many other variants are out there, and what makes the Delta variant so concerning?

“There’s ongoing surveillance to identify these variants. It’s important to recognize that as part of the lifecycle, this virus will mutate. Most of those mutations do not change the function of the virus, but some of the mutations can cause significant changes in how well the virus can transmit to others or the severity of the disease. And these are the two things that are looked at to identify the variants as variants of concern. The CDC actually has a website dedicated to identifying those variants of concern. Right now there are five variants of concern that meet these criteria. They’re either more transmissible or they’re able to cause more severe disease. The Delta variant is really the newest of these. It’s becoming the most globally dominant strain and it’s the most transmissible strain that we’ve seen to date. So out of the variants, this is the most transmissible. And that’s why we have such concern about it, particularly in our people that are susceptible, unvaccinated people,” Bowling said.

If we’ve already been vaccinated, what else can we do to protect others?

“For protecting others, if you’re fully vaccinated, one thing is to continue to spread the message that other people that aren’t vaccinated should get fully vaccinated. For people that are only partially vaccinated, reminding them that they should get the second dose, complete their vaccine course, and then of the same practices of the public health interventions that we’re tired of. But you can at least think about people that are not vaccinated, need to be more careful about going to crowded events. They also need to be more careful about masking. A lot of the more liberalized masking recommendations we’ve seen from the CDC really apply to people that are fully vaccinated and have very strong or intact immune systems. People that are immunocompromised for medical reasons or medicines that they’re taking or people that are unvaccinated are still at high risk for getting COVID-19,” Bowling said.

What are myocarditis and pericarditis?

“Myocarditis and pericarditis are similar. They’re both inflammation of parts of the heart. Myocarditis, specifically inflammation of the heart muscle, the wall of the heart and the pericardium is a layer of tissue that coats the outside of the heart. And so pericarditis is inflammation of that outer tissue. You can’t have both at the same time. The symptoms are very similar. People tend to have some chest pain. They may have some low-grade fevers with this as well,” Bowling said.

Some people have not gotten their children the second shot because they are concerned about myocarditis/pericarditis. How concerned should we be about heart problems related to the vaccine in young people?

“It’s definitely important for everybody to be comfortable with these vaccines and know about the side effects and potential risks. There was actually a meeting on June 23rd by the ACIP. It’s a group that provides advice to the CDC looking at the data that they have now on these reported cases of myocarditis and pericarditis. So there is overall a very rare event and that’s important to recognize. And it’s estimated that it’s about 12.6 cases per one million doses of vaccine, of second doses of the vaccine. Fortunately, most of the people that have had this myocarditis, pericarditis in this group have had very mild symptoms and it’s resolved with just rest. It’s gone away. They haven’t had any long-lasting complications from it. So it does exist, but it appears to be very mild and very self limited. It tends to go away pretty quickly. It’s also important to recognize that myocarditis and pericarditis can occur with COVID-19 infection itself. So actually, on June 23rd, after the ACIP met, there was a joint statement from multiple professional organizations. That includes the American Academy of Pediatrics, American Heart Association, American Hospital Association and many others that strongly encourages children to still, eligible over 12, to get vaccinated because the risk of getting COVID-19 and having myocarditis and pericarditis is higher than the risk of getting it from the vaccine itself. The other issue is that the myocarditis and pericarditis seen with COVID-19 disease can actually be quite severe, as opposed to the rare events that have been seen with a vaccine where it’s been mild and has gone away pretty quickly,” Bowling said.

People have not been as worried about children being affected by COVID-19. Why is that not a good idea, especially with the Delta variant?

“Children tend to have less severe disease with COVID-19 infection in general, which is great. However, when you have a large number of people infected, some children do still have severe disease. And we certainly have seen hospitalizations, ICU stays and deaths from COVID-19 in children. And actually now, since children are not eligible to receive the vaccine, they’re very vulnerable. We’re seeing more cases of COVID-19 in children in the younger age range because this Delta variant is so transmissible. And with that, we’re starting to see some of those numbers of hospitalized children, ICU stays and deaths. There’s also a risk for developing this multisystem inflammatory state in children, and that can involve things like myocarditis and pericarditis or inflammation of other areas of the body, too. And some of these can have long-term complications. They can have long-term issues with inflammation of the lungs and other issues of the body. And so you don’t want someone, even if it’s rare, to have an event that could be preventable by being vaccinated,” Bowling said.

Which is more common and serious: side effects of the vaccine or the impact of COVID-19?

“Complications from COVID-19 infection itself are still at a higher rate than those that we’ve seen with the vaccine, and they can be quite severe with long-term consequences. Obviously, we want to continue to monitor the vaccine for all safety signal and be transparent with anything that we’re recognizing. But it’s also very important to put it in context with things that we’re seeing with COVID-19. We still see terrible outcomes with COVID-19 disease and long-lasting consequences. For young children, young people that get COVID-19, they can have long-term problems with their hearts and lungs, and we want to avoid those. Those are preventable if they’re getting vaccinated,” Bowling said.

It has been such a relief to take off our masks and socialize again. But are there some precautions we should still observe?

“Fully-vaccinated people are now, per CDC recommendations, able to take their mask off and enjoy more events and activities than they were before, but it is still important to use some good common sense about where you’re going and recognize that some people may not be fully vaccinated. And that we’re still seeing COVID transmission in the community. And so, particularly if you are immunocompromised, if you have other medical problems that put you at risk for more complicated COVID-19 -- generally that’s having multiple medical problems. If you’re obese, if you have underlying lung disease or heart disease, you may be at higher risk for complications from COVID-19. So while being fully vaccinated is great, it’s the best protection you can get, you can still think about places that you’re going. And if you’re going, you may still choose to wear a mask if you want to for added protection or avoid large crowds, particularly when you know that you’re not going to be able to guarantee that some people there aren’t fully vaccinated or potentially having symptoms and have shown up,” Bowling said.

More on KSAT:

What should I know about the delta variant?


About the Authors:

Julie Moreno has worked in local television news for more than 20 years. She came to KSAT as a news producer in 2000. After producing thousands of newscasts, she transitioned to the digital team in 2015. She writes on a wide variety of topics from breaking news to trending stories and manages KSAT’s daily digital content strategy.

Cody King is a digital journalist for KSAT 12. She previously worked for WICS/WRSP 20 in Springfield, Illinois.