Dr. Heather Yeo, SurvivorNet Medical Advisor & Associate Professor of Surgery and Healthcare Policy and Research at Weill Cornell Medical College, joins Yahoo Finance to discuss the latest on the coronavirus pandemic.

Video Transcript

- Coronavirus infections are rising dramatically all over the US as the highly contagious Delta variant continues to spread. Nearly all of those cases have been found in the unvaccinated. But now there is a new variant that's gaining momentum. It's called Lambda. First detected in Peru back in August, the first US case was recently reported at a Texas hospital.

Here to discuss that with us now is Dr. Heather Yeo, medical advisor at SurvivorNet and Associate Professor of Surgery and Health Care Policy and Research at Weill Cornell Medical College. Dr. Yeo, thanks so much for being with us. Let's talk about this Lambda variant. What do we know? I know it's fairly new here. And do we know if the vaccines are effective against it?

HEATHER YEO: So far, there's no evidence that the vaccines are not protecting against the Lambda variant. What we do know is that this seemed to be the dominant version in Peru, as you mentioned, starting in December and has really caused a problem for them. However, in South American countries, there's been a much greater spread, less access to vaccinations.

And all the data we have so far, and all the information that we have from scientists, is that the vaccines are protecting against these variants. In fact, a article just came out in "The New England Journal" yesterday looking at the Delta variant in particular and showed that both the AstraZeneca and the Pfizer vaccines are protecting against these variants.

- So I actually want to pick up that piece there, Dr. Yeo. Let's just, again, really strengthen and make the case for people out there that are still not vaccinated why they should get vaccinated even as we are hearing these stories about some folks that are vaccinated still coming down with coronavirus especially as we see this Delta variant spiking. So if you could, again, just make that case why folks still need to get vaccinated even though they can still contract the virus.

HEATHER YEO: Yeah, this is really important concept. Vaccines-- or viruses in and of themselves can't replicate by themselves. They need a host, and we're the host. When a vaccine-- when a virus replicates, what happens is that there's potential for mutation.

And the more it replicates, the more opportunities it gets, meaning the more unvaccinated people there are, the more chances there's going to be more variation, a more chance that one of these mutations is going to be one that the vaccines can't protect against. So the more-- the more individuals that we have vaccinated, the less likely that these viruses are going to continue to mutate and spread and become more dangerous.

- President Biden held a town hall on CNN recently, and he was-- he seemed very frustrated with those who have not yet been vaccinated. He said, in fact, this is a pandemic for the unvaccinated right now.

And he also talked about getting the younger population vaccinated, saying that he hopes to have a vaccine approved within months for those under 12, which, of course, would be good timing since schools across the country are supposed to be reopening and many of them be in person this fall. What are you hearing within the medical community regarding vaccines for-- for that younger set?

HEATHER YEO: Yeah, I think as a medical professional, we are seeing that the people that are in the hospital-- I mean, it's all over the news. The ones that we're seeing in the hospital are-- the majority of those are unvaccinated. As a parent myself, my-- I'm lucky. My kids are both over 12, so they're both vaccinated. But for those with young children, it's a real dilemma because there hasn't been access yet. And I think it's really important that we are able to get something hopefully in time for schools to open and have more availability for-- for students to be in person.

- What happens if we don't, Doctor? Is there concerns that-- we talked a lot about how children really aren't too badly impacted by the virus. But if we don't get a vaccine for some of those younger children, they go back to school-- I know there are some mask mandates in some states-- what is the fear of what could happen, again, as we now have this Delta and now this Lambda variant is still unclear how dangerous or how transmissible that variant is going to be?

HEATHER YEO: I mean, I think one of the biggest fears is that children are vectors even though many of them aren't getting very sick. They do have the potential to transmit particularly in areas where the vaccination rates are low. I'm lucky. I'm in New York, and we just surpassed over 70%-- I think 75% of our population vaccinated. So we're starting to get closer to potential herd immunity for those individuals that aren't vaccinated.

But again, in children under 12 are not-- don't have a vaccine yet. And there are individuals who are immunocompromised who can't always take vaccines or don't have an active response to vaccines. And we're worried that those are going to be patients put at risk if people-- other people who have the opportunity aren't vaccinated.

- You mentioned, Doctor, you're in New York. Over in LA, you know, they reinstituted mask wearing indoors, even for those that are vaccinated. Do you think we're going to see more cities do that across the country? And is that going to be an effective way to keep us safe until more people are indeed vaccinated?

HEATHER YEO: Yeah, I mean, I think it's important. I got my mask right here. We're vaccinate-- in the hospital, we're using full precautions with all our patients. We're masking. We're wearing goggles to protect any sort of transmission that way. And I think that if we have continued mutation and low vaccination rates, again, there's the potential for additional mutations. Currently, there aren't any that we know of that are resistant to the current vaccines that have been developed, but the continued mutation does put it at a possibility that there might be some.

- I'm actually really glad that you mentioned that because that was actually one of my questions, that every variant that we now see come out, all of these new mutations-- because I'm not a virologist-- do they become more severe, more resistant to vaccines? So meaning that every new variant that we really hear coming down the line, are they more and more dangerous than the ones we've dealt with already previously?

HEATHER YEO: So we don't really know on an individual basis. Just like every year people screen and monitor for flu variations, that's the same thing that virologists are doing right now. They are studying the genetics of these different viruses. And they're looking at the key components that make the vaccines work.

So they're looking at the spike protein. They are looking at where the virus-- the different components of viral replication and seeing if there are mutations in those areas. So the WHO and the CDC have-- have listed different variants of interest, of concern, and variants that they think could be high consequence. We haven't seen the high consequence variants yet, but they're-- they're out there monitoring.

Just like any mutation, there's natural selection, right? So if-- if something mutates, and it doesn't make it more susceptible, that won't continue to get spread. But if it mutates, and it is-- individuals are more susceptible, it might make it easier for it to spread or more contagious or harder for us to detect with the current testing. That we have and all of those things have the potential to change the course of the virus.

- All right. Dr. Heather Yeo, medical advisor at SurvivorNet, Associate Professor of surgery and Health Care Policy and Research at Weill Cornell Medical College. Always great having you here with us, Doctor. Thanks so much.