AYESHA RASCOE, HOST:
Hundreds remain in quarantine in South Carolina as a measles outbreak accelerates. There have been over 100 confirmed cases of the disease in the state so far and many more who could've been exposed. At the same time, a smaller outbreak continues along the Arizona-Utah border. Joining us now to talk more about this is Dr. Carlos del Rio. He's a professor of medicine in the Division of Infectious Diseases at Emory University School of Medicine. Welcome to the program.
CARLOS DEL RIO: Good morning, Ayesha. How are you?
RASCOE: I am good. But - so this - measles is highly contagious, obviously, but it's also preventable. What's driving these outbreaks?
DEL RIO: Well, Ayesha, as you said, measles is one of the most contagious infectious diseases. One person infected with measles infects probably another - probably 16 individuals or so. So clearly, nine to 18 could be infected. So clearly, this virus also is transmitted through respiratory droplets. The virus stays in the air. So if I have measles and I'm in a classroom and I leave, the virus stays in the air for several hours. So other people can come in and get infected.
You are infectious several days in the order of, you know, four days before you have rash or symptoms and four days after the onset of rash. So you - a kid can be feeling totally fine and still be infectious and will get sick later. So if your vaccination rates drop - and they don't need to drop a lot. We need to keep vaccination rates in the population above 95%. And the moment you start dropping below 95%, you start seeing outbreaks happening. You know...
RASCOE: Is that what happened? Because just 25 years ago, the U.S. was declared functionally measles-free due to vaccination efforts. Like, what went wrong? Like, how do we get to where we are now?
DEL RIO: Well, you know, there's been - as you know, there's been a lot of doubts about vaccines. And what happens is, we're victims of our own success, right? Measles vaccination eliminates measles. People don't see measles anymore, so they start asking, why do I need the vaccine? And at the same time, you have all sorts of, you know, misinformation out there saying, well, the measles vaccine is associated with autism, which it's not. The measles vaccine is not good. It's better for kids to get measles, which is absolutely wrong. So you start getting misinformation. So parents start saying, well, why should I vaccinate my kids?
So again, you don't need a lot of kids to not be vaccinated. It needs to drop just a little bit. And the moment you start seeing that drop, you start seeing cases. South Carolina, for example, that is having a major outbreak right now, their estimated vaccination percent among school-aged children is about 92%. So it's not very, very low, but you have to bring it up.
RASCOE: OK.
DEL RIO: And if you bring it up, then it's a different story. But if you don't bring it up, then you have a problem.
RASCOE: Well, what do you make of the current state of vaccination? Because as you mentioned, yes, there has been a lot of antivaccine misinformation. You know, there - it was in opposition to the COVID-19 vaccines during the pandemic. But lately, the opposition has seemed to spread to all vaccines. So what do you make of this moment that we're in?
DEL RIO: Well, I'm very, very sad and disappointed as an infectious disease physician. I really don't like to see diseases that could be eliminated, right? Measles is a disease that we can control, we can get rid of. We can be - the Americas at some point in time was measles-free. The U.S. - you know, we had vaccination programs, but now we're having all sorts of things like, you know, not having vaccination mandates at schools, doing this, doing that. And that is - just a little bit is necessary. If you're permissive and you start dropping rates of vaccination, you start seeing outbreaks happening. And unfortunately, you know, this is very sad because we could eliminate those diseases. We could control them. There's no point on having kids get measles.
And again, measles - when you get infected with measles, natural measles is not a benign disease. We need to remind people that before we had vaccines in the United States, in the 1950s, there were about 4 million cases per year, and out of those 4 million cases, there were about 500 deaths. You know, you talk about 500 children that died unnecessarily. Even in the current outbreak we're having in the U.S. - close to 2,000 cases - there've already been three confirmed deaths. That's unacceptable. We shouldn't have healthy childrens die.
RASCOE: You're a practicing physician and an educator. Have you changed how you talk to your own patients or students about vaccination?
DEL RIO: Oh, very much so. I really want to emphasize the importance of vaccines, and it's not just the measles vaccine. It's all other vaccines. You know, we see how there's changes in the hepatitis B vaccine, another fantastic vaccine. There's, you know - there's a herpes zoster vaccine for adults. There's a human papillomavirus vaccine that prevent girls, you know, from getting cervical cancer. We have vaccines that have been one of the greatest advances of science and which really have made an impact on infectious disease. And for me to see those vaccines being not utilized, it's really disappointing. And, you know, again, a country like the U.S., which has access to vaccines, which is wealthy, should not be seeing that.
RASCOE: That's Dr. Carlos del Rio. He's a professor of medicine and infectious diseases at Emory University. Thank you so much for joining us.
DEL RIO: Happy to do so. Transcript provided by NPR, Copyright NPR.
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