DURHAM, N.C. – Another national explosion in hospitalizations and deaths from COVID is unlikely – even as new variants emerge – because so many Americans have been vaccinated, previously infected or both, Duke health experts said Thursday.
Still, it is wise for people to be cautious, keep an eye on what’s happening in their communities, and wear masks when they think it necessary, they said during a virtual briefing for journalists.
The two scientists discussed air travel, lingering COVID symptoms, masks, the need for greater faith in public health, and other topics related to the pandemic. Watch the briefing on YouTube.
Here are excerpts.
ON WHAT IS KNOWN ABOUT NEWEST COVID VARIANTS
David Montefiori, director, Laboratory for Aids Vaccine Research and Development
“There are several forms of the BA2 sub-lineage now that are apparent and showing some signs of spread.
“One of them in particular, called BA2.12.1, is really starting to take off in the United States and other parts of the world. It’s becoming the dominant variant in certain places in the United States like New York City. So far, what we know … is that it doesn’t appear to cause any more severe disease than the earlier forms of Omicron or other variants.”
“What we’re really interested in the most right now is, does it pose a greater threat to the vaccines? Is it going to be more of an escape variant?”
ON WHETHER ANOTHER SURGE IS COMING
Dr. Cameron Wolfe, infectious disease specialist
“Locally for us in North Carolina we have not seen, reassuringly, a significant jump in the numbers of hospitalized patients yet. That said, some of our European colleagues who have been a step ahead of us … have seen increasingly hospitalizations.”
“We’ve learned a lot more over the last couple of years in terms of how to handle surges of patients, should they come, although internally I think we remain more optimistic about these variants compared to previous ones given good vaccination rates now in our community, and decent adaption within hospitals about how to handle them.”
ON HOW CONTAGIOUS NEW VARIANTS ARE
“We have seen multiple waves of variants … each time, these variants acquired a higher degree of transmissibility. I think we are maybe starting to see a tipping point where the virus is continuing to become more contagious … but at some point I think the virus is going to reach a tipping point where it’s just not going to be able to acquire any greater improvement in transmissibility. When we’ll reach that point is really difficult to say, but we are seeing the virus continuing to be able to evolve and become more contagious.”
“The good news is these variants do not appear to be any more pathogenic. They are not causing more severe disease; that’s a good thing. And as far as we can tell, the vaccines are still very effective against all of the variants. It’s very important to know it’s important to get boosted for protection against the Omicron variants.”
“Hopefully the virus will not be able to find a way to eventually evade our vaccines. That’s just an unknown question at this point.”
ON MASKING ON AIRPLANES, ELSEWHERE IF NOT MANDATED
Dr. Cameron Wolfe
“If you’re flying internationally, be very careful. The international rules on your carrier may be entirely different than in the United States.”
“In terms of risk, there was a lot researched early on in the pandemic to show that contour of air flow on planes was very effective in reducing risk. But I think it’s a misnomer to assume that risk is zero. We’ve also have data cemented to say the risk is not zero if, for example, the person next to you is positive.”
Equally, there’s clear data to say that masks are bidirectional in their effect. I don’t change my message in light of this week’s federal mandate changes, to my immunosuppressed patients, to say your best protection as an individual is to wear your mask. That’s something you can control, particularly on longer flights or at times when you’re not in a controlled situation.”
“We have to acknowledges it increases the risk of transmission risks if the person besides you no longer has any layer of protection that shields viral spread. There is increased transmission risk in that situation. Is it low enough in the current setting of relatively quiet transmission to take away a mandate? That’s a political question at that point. But I certainly counsel patients to say, ‘Look, you need to assume public transport risk is not zero.”
“We’re encouraging people to make individual decisions about health risk, and that’s appropriate. I can make an individual choice to go to a restaurant, for example.”
“We think about planes; planes are a bit of a luxury. I also think of metro and buses and trains as means of public transport that these rules impact. For those individuals (who rely on public transportation), I think there’s still pretty compelling reasons why they should think carefully about masks.”
ON TESTING FOR NEW SUBVARIANTS
“Fortunately, the tests aren’t affected very much by the variants. They are based on multiple portions of the virus … so far the tests, for the most part, are still very effective with all these variants and subvariants of the virus.”
ON GETTING ACCURATE CASE COUNTS NOW
Dr. Cameron Wolfe
"You have to concede the numbers are a significant underestimate of the actual burden of COVID in our community. But that has always been the case. There has always been testing variability across many states and jurisdictions over the last two years.”
“Irrespective of how many tests you do, the hospital line in the sand as to how sick you need to be to come into the hospital has really not changed. Hospitalization has always been a fairly fixed end point and measure of how much impact COVID is having on a community, which is unrelated to how often you deploy a test.”
ON REACHING ‘ENDEMIC’ STAGE
Dr. Cameron Wolfe
“The question of ‘endemic’ activity is sometimes interpreted in different ways. There’s the biologic definition of endemic; we should expect this virus will be with us in various ways hereforth.”
“But I think ‘endemic’ is misconstrued in the public discourse to mean ‘when do we go back to normal?’”
“When we were in omicron we still had hospital shortages, we had patients who were being diverted, we had activity that was curtailed, we had lots of public transport, restaurants, activities that were not being able to be performed because of the impact of the virus on our community.”
“But what you’ve seen over the last few months is you’ve seen our response from a public health standpoint return to a much more (calm, normal, controlled process). We’re trying to accommodate the virus, co-exist if you will.”
ON HERD IMMUNITY
“I think we’re seeing a really major impact of herd immunity on the pandemic, not so much in terms of re-infections but in terms of disease severity and death. They’re going down remarkably.”
“Even in the omicron wave, we had this huge spike in infections, but we did not see the corresponding increase in severe illness and deaths you would have expected from a spike that high. This is evidence that pre-existing immunity is having a major impact on the pandemic in terms of preventing serious illness and death. It can be improved and will be improved if more people will get boosted.”
“We were very fortunate during the delta wave that preceded omicron, that the CDC recommended people get boosted. That was controversial at the time as far as whether a boost was really needed for delta. It was fortuitous because people were getting boosted, and the boost really was needed for omicron. So we got a head start.”
“Here we are months later and we still have at least half the people in the United States who are eligible for a booster shot that haven’t received one. I can’t emphasize enough how important it really is to get boosted for omicron. There’s no question about the need now.”
ON STRUGGLE OF LINGERING SYMPTOMS
Dr. Cameron Wolfe
“Lots of people have lingering symptoms. That’s one of the real challenges of COVID. Particularly a post-viral cough, which we see for lots of illnesses, is very common here. Fatigue is very common. A third patients will report, a month down the road, that they’re very fatigued.”
“Even though people often have symptoms that are more protracted than seven to 10 days, their likelihood of having viral virus beyond that point is incredibly small. Which leads to all the public health decisions, to say we don’t need isolation for infected people longer than a seven-to-10 day window or the five-to-10-day window you see now.”
“Even in the people who are the most sick; immunosuppressed people who don’t respond well … we feel very comfortable after a 20-day window.”
“I think it’s entirely appropriate for people as they recover out of that, as they start to head back to work, to use that as a time to have a mask. We see that as kind of the guidelines. On days six to 10 you can return to activity with a mask on. I think that not only is the right medical thing to do in case you’re one of the rare people who remain infectious … but it also offers comfort, frankly, to the people around you. They feel more reassured that they’re not going to get sick.”
ON WHICH MASKS ARE BEST
“Any mask is better than nothing at all. The most effective masks are the N95 masks and the KN95 masks. They’re far better than the surgical masks or just wearing a cloth mask. It would have been helpful if that message had got out to people sooner and more people were using those masks. They’re far better than any cloth mask.”
ON WHETHER THERE WILL BE ANOTHER NATIONAL SURGE
“I tend to think that because of all of the population immunity that we have now, we’re not going to see a huge spike in, especially hospitalizations and deaths, that we’ve seen multiple times in the past. And that’s a good thing.”
“All of these variants that continue to emerge, it’s very important to keep monitoring them. But there are always going to be new variants to emerge. We can’t get real concerned about them every time. We’re really tuned into looking at the statistics, which can cause a lot of anxiety. We just have to get used to the fact that this virus is going to be with us for a long time and it’s going to continue to evolve.”
“Unless it becomes more severe in terms of the disease that it causes, which is not what viruses tend to do. If anything they tend to evolve and become less severe … that would create a real problem that would cause a lot of anxiety. Right now I don’t see that happening.”
ON REBUILDING TRUST IN PUBLIC HEALTH INSTITUTIONS
Dr. Cameron Wolfe
“We’ve had a rich history (before) the pandemic of public health being a body that is cautious and is trusted and I think we have seen many attempts to undermine that, frankly, in the last couple of years that have been difficult to witness.”
The most recent change (to the mask mandate), I’ll be honest, does worry me less immediately about the impact on flight safety and worries me more about trust. It worries me about trust in public institutions, particularly at the CDC level, but frankly this feeds down to local public health as well. How we go about serving trust in our community to a population that seems increasingly willing to not listen to good science and good public health.”
“I think it’s a real challenge moving forward and actually one of the biggest things we try to learn out of this is how do we communicate scientific information accurately? How do we build trust back to say we’re all aiming for the same thing here? How do we allow leaders like the CDC to get back to a position that’s trusted enough such that if we had to make a significant intervention … that the public in general has enough faith in the decision-making?”
David Montefiori is a professor and director of the Laboratory for AIDS Vaccine Research and Development at Duke University Medical Center, where he has studied the effectiveness of COVID-19 vaccines against new variants of the virus.
Dr. Cameron Wolfe
Dr. Cameron Wolfe is an infectious disease specialist at Duke Health and an associate professor at the Duke University School of Medicine. His areas of study include infectious diseases and biological and emergency preparedness for hospital systems.
Duke experts on a variety of other topics related the coronavirus pandemic can be found here.
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