CDC urges caution as states ease COVID restrictions and travel picks up

The CDC is warning the U.S. could seen another surge of COVID-19 if Americans don't take precautions this spring. CBS News' Manuel Bojorquez report from Miami, then Dr. Amesh Adalja, an infectious disease expert and senior scholar at Johns Hopkins University's Bloomberg School of Public Health, joins CBSN to discuss the latest.

Video Transcript

ELAINE QUIJANO: There are mounting concerns the US may soon see another surge in coronavirus cases. Health officials are urging Americans to take precautions this spring, even as more states ease their restrictions. There have been more than 29.4 million cases nationwide and more than 535,000 lives have been lost. The warnings come as travel picks up nationwide.

Spring breakers flocked to Miami over the weekend. More than 100 people were arrested after ignoring coronavirus safety protocols. Meanwhile, major European nations are halting the use of AstraZeneca's coronavirus vaccine. There have been more than 30 cases of recipients developing blood clots, but the company is pushing back.

For the latest on this and the warning about cases here at home, Manuel Bojorquez reports from Miami.

MANUEL BOJORQUEZ: Tonight, the CDC is warning Americans of another COVID surge as people travel for spring break.

ROCHELLE WALENSKY: I'm pleading with you for the sake of our nation's health. These should be warning signs for all of us. Cases climbed last spring. They climbed again in the summer. They will climb now if we stop taking precautions.

MANUEL BOJORQUEZ: More than a million travelers passed through the nation's airports on Friday, the highest number since the pandemic began. They were heading south and crowding the coast, including rowdy groups in Miami Beach.

- We're really swimming upstream when it comes to trying to get people to follow safety practices.

MANUEL BOJORQUEZ: That's a concern, especially given that the variant's here in South Florida.

- Yes. And that's the frightening thing. We don't want to become a super spreader.

MANUEL BOJORQUEZ: Florida has the most known cases of the highly contagious variants nationwide.

- My biggest concern is that the variants overwhelm our current efforts. So let's be real about what's going on.

MANUEL BOJORQUEZ: No spring break for Duke University students. More than 6,000 are locked down on campus after fraternity parties fueled a COVID spread. The University told students, "If this feels serious, it's because it is." Still, nationwide more restrictions are being lifted. Los Angeles today reopening gyms and indoor dining for the first time since last summer. New York State is now allowing wedding receptions with 50% capacity.

Overseas, there are questions about whether AstraZeneca's COVID vaccine could cause fatal blood clots. At least 10 countries are suspending the shots. AstraZeneca says its drug is safe, and it's expected to file for authorization in the US this month or early next, where more people are getting vaccinated. Nearly 3 million shots were reported on Friday, a one-day record.

[MUSIC - YO-YO MA]

Including Yo-Yo Ma, who gave an impromptu concert after receiving his second dose, saying he just wanted to give something back.

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Another return to normal would be reopening schools. A new study suggests that students can be safely spaced apart at 3 feet as opposed to 6 feet, provided they are wearing masks. The CDC is set to be reviewing that data. Elaine.

ELAINE QUIJANO: Manuel Bojorquez, thank you. Infectious disease expert Dr. Amesh Adalja joins me now. He's a senior scholar at Johns Hopkins University's Bloomberg School of Public Health.

Dr. Adalja, welcome. Good to see you again. Several European countries are seeing another surge in coronavirus cases. The CDC is warning the same could happen here in the US if we let our guard down. How concerned are you about another wave?

AMESH ADALJA: I'm less concerned about another wave happening in the United States than in Europe, because we are doing much better when it comes to getting vaccines into people's arms. We're getting millions of doses every day, so I do think we're able to stay ahead of the variants. I think we have to be vigilant. We have to keep tracking these variants.

And-- and those variants are what's likely responsible for the surge in Europe. We don't completely let our guard down, but I do think we have a little bit of a cushion because we're doing so much better with the vaccine. But people who are not vaccinated still need to be careful and still think about washing their hands, wearing face coverings, and avoiding crowded and congregating places until more of us are vaccinated.

ELAINE QUIJANO: Well, the CDC says the variant first identified in the UK is still on track to be the dominant strain in the US by the end of March. Current vaccines are effective against this variant. Is this still cause for concern?

AMESH ADALJA: Not-- not as much as some of the other variants. What we see as the UK variant is definitely increasing in the United States, but overall cases are going down because we're getting so much vaccine into people's arms and because we've got some population-level immunity from prior infections. The key to keeping the UK variant at bay is to accelerate vaccination as fast as possible.

If we can get our vulnerable populations vaccinated, what we'll start to see, and we're already starting to see it, is decreases in hospitalization while cases may stay at a relatively high level. But what we're doing with this vaccine and with this variant is basically removing its ability to cause severe disease. And that's the goal of all of this. We are not going to get to COVID zero. What we're trying to do is tame this virus.

ELAINE QUIJANO: Well, Dr. Fauci says the CDC is looking at possibly updating its social distancing guidelines for schools. A Massachusetts study showed 3 feet instead of 6 may be enough under certain circumstances. What exactly are those circumstances?

AMESH ADALJA: Well, the circumstances are if you've got your-- the students all wearing masks, then you can decrease from 6 feet to 3 feet. And this study from Massachusetts, from New England really shows that this is something that you can do. And I think it should be a priority, because one of the obstacles to opening schools has been do you need to social distance a certain amount?

And I think if you can get mask wearing to be the norm in schools, and I think it should be and it will be, I do think this makes it much easier for some schools that may have constrained space to be able to open up and to be able to do things at a 3-feet range. The schools have been closed for far too long. This needs to be a priority. It hasn't been a priority. Hopefully now we're finally on a track to getting in-person schooling back on-- back in place.

ELAINE QUIJANO: Well, Germany, France, and Italy have joined a growing list of countries to temporarily suspend the use of the AstraZeneca vaccine over mounting concerns of blood clots. European officials insist the benefits of the vaccine outweigh the risks. Doctor, what's your take on this?

AMESH ADALJA: I agree. I do think the benefits of the AstraZeneca vaccine outweigh the risks. And I am not someone who thinks that these blood clots are necessarily related to the vaccination. Just because an event happens after a vaccine doesn't mean the vaccine caused it. This could be a correlation, a spurious association, not something that's really causal.

And if you look at the data that they're providing, it doesn't appear that people who got the AstraZeneca vaccine had any higher rate of blood clots than the background rate. So I think this is the wrong decision that's being made in many European countries. And I-- and I wonder about the implications, because it might have a cascading impact and decrease people's confidence in the AstraZeneca vaccine, which is an important vaccine that really is a key to controlling this virus in many parts of the world. And eventually, we likely will have this vaccine in the US.

ELAINE QUIJANO: Well, a study published in the journal "JAMA Network Open" found severe coronavirus cases can affect brain function. Doctor, what have we learned about COVID and its link to neurological symptoms?

AMESH ADALJA: So there are people who have severe COVID that are in the ICU and that are hospitalized, and they start to develop neurologic symptoms. For example, they may become delirious or they may have difficulty moving certain parts of their body. And what this study shows is that there is kind of a syndrome, what we call COVID encephalopathy, where COVID is affecting brain function in certain individuals, especially those with severe disease.

And the study really talks about types of-- types of imaging you can do, MRIs, EEGs, these types of studies in order to understand what's going on in these people. And I think this is not surprising. We know that critical illness of any sort can affect brain function. So those individuals who are with COVID who develop neurologic symptoms, it could be part of a syndrome of COVID brain-related dysfunction. And I think we need to know a little bit more about it, but it's something that clinicians have to be alert to when they're taking care of hospitalized COVID patients.

ELAINE QUIJANO: All right, Dr. Amesh Adalja. Dr. Adalja, thank you very much.

AMESH ADALJA: Thank you.