Indian Variant in the U.K.; Continue COVID Health Measures?: It’s TTHealthWatch!

TTHealthWatch is a weekly podcast from Texas Tech. In it, Elizabeth Tracey, director of electronic media for Johns Hopkins Medicine, and Rick Lange, MD, president of the Texas Tech University Health Sciences Center in El Paso, look at the top medical stories of the week. A transcript of the podcast is below the summary.

This week’s topics include vaccinating adolescents for COVID-19, atrial fibrillation monitoring and stroke, the Indian COVID variant in the U.K., and vaccinations and public health measures to control COVID infection.

Program notes:

0:41 The Indian COVID variant in the U.K.

1:41 When full vaccine schedule is followed

2:43 One dose not very effective

3:04 COVID vaccines in adolescents

4:04 Large enough number of infections

5:04 Not for preventing severe disease

5:27 Vaccination and public health measures for COVID

6:28 If we continue both things

7:29 Incidence of flu

7:41 Monitoring after ischemic stroke for atrial fibrillation

8:41 Found in 12.1% with internal monitor

9:42 Should we implant everyone after stroke?

10:47 Most of the AF occurred months after stroke

12:22 End

Transcript:

Elizabeth Tracey: How effective is a single vaccine dose against the COVID variant from India?

Rick Lange, MD: Thinking of effectiveness, how effective is the COVID vaccine in adolescents?

Elizabeth: If you’ve had a stroke, should you be monitored and should you have an external or an internal monitor?

Rick: And while we’re vaccinating, do we really to be wearing masks and socially isolated?

Elizabeth: That’s what we’re talking about this week on TT HealthWatch, your weekly look at the medical headlines from Texas Tech University Health Sciences Center in El Paso. I’m Elizabeth Tracey, a Baltimore-based medical journalist.

Rick: And I’m Rick Lange, president of Texas Tech University Health Sciences Center in El Paso, where I’m also the dean of the Paul L. Foster School of Medicine.

Elizabeth: Rick, why don’t we turn first to all of our COVID material? We’re back to that. In the BMJ this week, this is just a brief report, the U.K. government has taken a look at what is becoming an increasing problem for them, which is the emergence — or should I call it the takeover — of the Indian variant of COVID-19 in the U.K.?

We should just note, of course, that nomenclature relative to these variants has changed. The WHO has just announced that now we’re going to be referring to them all as Alpha, Beta, and so forth until we run out of those, and then they’ll think of something new. Fortunately, that gives us 21 different variants that we could name before we run out.

In this case, they took a look at — it’s a preprint — a paper released by Public Health England that was looking at the Pfizer vaccine, the AstraZeneca vaccine, and their effectiveness against these two variants that they’re coping with right now.

They found that in general, when the full vaccine schedule is followed, there is really effective protection, but the bad news is both vaccines were only 33% effective against symptomatic disease from this variant that’s emerged from India 3 weeks after the first dose only. So it really calls into question, of course, their practices of reopening right now, and particularly in view of the data relative to how many of those cases are emerging in the U.K., raises a lot of concerns.

Rick: Elizabeth, they’ve been on a different vaccination schedule than we have, of the two vaccines in the U.S. that require two doses. In the United Kingdom, when they had fewer vaccines available, what they focused on was making sure everybody had their first vaccine and then they give their second vaccine as long as 12 weeks afterwards.

What these studies show, as you alluded to, is that’s not very effective for these particular variants, and specifically the Indian variants. Now, if you get two doses, very effective. Only one dose, not very effective. So what that’s going to force them to do is to come closer to the timeline that we’re giving the doses in the United States, and as you mentioned, it’s not relaxing the other measures, the social isolation and the masks, that we’re going to talk about in another study.

Elizabeth: Yeah, very concerning, and of course Vietnam has announced that they’ve identified a variant that also looks a little bit concerning. Since we’re talking about vaccines, why don’t we move to the New England Journal of Medicine? This is a look at how effective are vaccines in adolescents.

Rick: This was looking at the Pfizer vaccine. It is approved for individuals 16 years of age and older. I say it is. It wasn’t till mid-May, because that’s when most of the studies were done, and this attempted to look at, “Gosh, is it safe and is it effective in younger individuals?”

This was a placebo-controlled, observer-blinded study in which almost 2,300 adolescents either received two doses of the Pfizer vaccine at the same doses that were given to adults, or they received placebo, and then they followed these individuals. Actually, it’s interesting, Elizabeth. What they were looking at primarily was the immunogenicity, that is did you develop a robust antibody response. They really weren’t going to look at the clinical efficacy because they didn’t think there would be that many infections in the placebo group.

Well, the first thing they discovered was there is a robust antibody response. In fact, it’s 76% more robust than it is in older individuals, but what they had was they had a large enough number of infections in the placebo group to determine that the vaccine is 100% effective.

Now, the next thing you ask is, “Are there side effects?” It looks like they’re very mild, transient side effects, similar to what adults get. About 80% developed some injection site pain, about 60% to 65% developed fatigue, and about 55% to 65% developed headache, but there were no serious side effects at all.

Elizabeth: I find it really interesting, the robustness of the immune response relative to antibody production. I think that this is one opportunity that’s being presented right now to all of us regarding that kind of information. I’m not sure that we’ve ever looked very closely at how antibody production secondary to immunization might change during the lifetime.

Rick: In fact, as the authors of this particular study note, it’s the younger kids that seem to have a more robust immune response. Now, these kids, as we’ve talked before, are less likely to get severe disease. We’re not going to be preventing severe disease, but it’s going to contribute to herd immunity. In fact, last night, Elizabeth, on our campus, we’ve started a campaign to immunize these kids so they can be getting involved in sports again, and in socialization, and going back to school in the fall, and more importantly, protecting their older relatives that may have comorbidities.

Elizabeth: Exactly. Well, instead of completely changing our topic, why don’t we have you do your second one right now? That’s in JAMA Network Open. This is taking a look — it’s a modeling study — at what about immunizations and what about all the other public health measures that we’ve instituted? How do they curtail, or not, infections?

Rick: In fact, this is particularly important not only in the U.S., but in developing countries where the vaccine rollout is going on but isn’t really as robust as it could be.

What they did was they said, “Listen, we have the vaccine and we have these nonpharmacologic interventions like social isolation and mask-wearing that’s meant to prevent the spread among individuals. If you’re doing vaccinations, do you still need to continue these practices and if so, for how long?”

The second question is, “Is it more important to have a really effective vaccine that only a smaller group get? Or if we targeted a larger group of the less effective vaccine, what are the results there?”

In the modeling, here’s what they did. They took North Carolina that has about 10.5 million individuals and they said, listen, if we continued both things, the vaccinations and the nonpharmacologic interventions, they determined that approximately 1.8 million infections and 8,000 deaths could be prevented during that 11 months. By the way, you lose that effectiveness if you stop the nonpharmacologic interventions. If you stop mask-wearing and you stop social isolation before people were fully vaccinated, you don’t have those benefits. Furthermore, it was more important to get more people immunized, even if the vaccine wasn’t as effective, than it was to get the most effective vaccine that only 20%, 25% of the individuals would take.

Elizabeth: I would just note that with regard to other infectious diseases, a lot of them, and especially even those in children, since we’ve all been mask-wearing and socially distancing from one another, those have declined dramatically. Sp I think there is a tremendous amount of evidence that we ought to be just — and hand washing — be engaging in these practices a good deal more going forward.

Rick: In fact, they’ve put numbers on it. The incidence of flu has gone down 99.7% as a result of what we’ve been doing. Now, we’re not going to be able to maintain all that. What we can do is, again, we can insist upon mask-wearing and social isolation, and use that as an impetus to tell people to get vaccinated.

Elizabeth: Let’s turn now to JAMA. These are two studies that are taking a look at this issue of ischemic stroke and the monitoring of people subsequent to that because of the relationship between atrial fibrillation and subsequent stroke.

Let’s talk first about the first trial, which is the STROKE-AF randomized clinical trial. They had 496 patients. They were younger, actually, 50 to 59 years. These people had had a stroke with one additional stroke risk factor. Their stroke was attributed to large or small vessel disease. They got randomized to either the intervention group, where they had an implantable monitor that was inserted within 10 days of their index stroke, or the control group, who also were monitored with an external cardiac monitor.

They looked at atrial fibrillation detection and in this group they detected it at 12 months significantly higher with the implantable monitor. They found it in 12.1% versus 1.8%, so we’re finding it a lot. Is that surprising? I’m not sure I think that’s surprising.

In this second one, again, they were taking a look at this implantable versus the external monitoring in people who had had ischemic stroke, and in this case it was cryptogenic. They had 300 patients within 6 months of ischemic stroke and without known atrial fibrillation who were monitored in this one, and again, more patients who were detected with atrial fibrillation at 12 months with the implantable device.

All right, so let’s turn to the editorialist who I think very carefully tries to run on this little edge between what should we do here and really very honestly comes back to the idea that we don’t really know yet what to do, whether we should be implanting these monitors in people after they have strokes. What are your thoughts?

Rick: Elizabeth, I think you’re absolutely right. These are people that weren’t known to have atrial fibrillation and they thought their strokes were due to other reasons. They determined that about 1 in 7 individuals had at least 2 minutes or more of atrial fibrillation wearing an implantable monitor.Usually this is inserted underneath the skin and it monitors the heart rate for a year or two.

You could make a case, “Well, gosh, maybe we ought to be putting these in everybody.” But once you’ve determined that someone has atrial fibrillation, do they actually benefit from treatment or not? Because these are asymptomatic, they may be relatively short, and we know that the longer a person is in atrial fibrillation the higher their risk of having a stroke related to that. At this particular point, I’m not sure that we have enough information to make a recommendation. Do you put an implantable monitor in everybody? If you find it, do you put those people on oral anticoagulation? Those are the next studies that will be coming out.

Elizabeth: Yeah, so I think that’s exactly right. It raises a whole lot more questions, and of course, putting somebody on anticoagulation has its full set of consequences.

Rick: More to come. These are extremely well-done studies. The thing I found very interesting in the first study, the STROKE-AF, is most of the atrial fibrillation didn’t occur in the first month after the stroke. It occurred subsequent months after that, and than even if people have atrial fibrillation, when they’ve had monitors in them and they’ve developed a stroke, oftentimes it’s not when they’re in atrial fibrillation.

It begs the point that people sometimes think that people what they have is an atrial myopathy. There’s something not just about the atrial fibrillation, the rhythm, but there’s something about the atrium. It’s either too big or it’s too sticky, the clots form. Maybe we’re focusing on the wrong thing. Maybe the atrial fibrillation is a monitor for a dysfunctional atrium and maybe that’s what we need to be looking for instead, so stay tuned. Well, I’m sure we’ll be reporting this further in subsequent years.

Elizabeth: Yes, as is the object in many serious research studies, raises two questions where one existed before.

Rick: Yep. But clearly in people that have symptomatic atrial fibrillation, they need to consult with their healthcare provider to determine whether they should be on anticoagulation. If so, what’s the proper type?

Elizabeth: What would you say is the role of monitoring in that?

Rick: If someone has symptomatic atrial fibrillation and a number of risk factors, they get put on anticoagulation regardless of what the monitor shows. It depends upon the number of risk factors, what’s called a CHA2DS2-VASc score, and that’s why I said seek your healthcare provider because not everybody needs to be on it, and even people that need to be on it, there are different types available.

Elizabeth: Very good. On that note, that’s a look at this week’s medical headlines from Texas Tech. I’m Elizabeth Tracey.

Rick: And I’m Rick Lange. Y’all listen up and make healthy choices.