SCOTT SIMON, HOST:
New numbers are out from the CDC, and they report more than 300 cases of measles this year - the highest number since 2019, and it is only March. Most of those cases are related to the outbreak in west Texas and neighboring New Mexico, but 13 other states now report cases, too. How much are people both vaccinated and unvaccinated at risk? Dr. Carlos del Rio is a professor of infectious diseases at Emory University School of Medicine in Atlanta. Dr. del Rio, thanks so much for being with us.
CARLOS DEL RIO: Happy to be with you.
SIMON: What's your reaction to these new numbers?
DEL RIO: Well, it's not surprising, Scott. You know, after COVID, we saw a drop in the immunization coverage, and we haven't really recovered. And measles is a highly transmissible infection. The term we use in infection is called the R-naught, which is the number of infections caused by one case. And just to take you back to COVID, during COVID, the R-naught was three to five. So, you know, one case of COVID led to three other infections or five other infections, at most. In measles, that number is closer to 18, which means one case of measles leads to 18 cases.
SIMON: So you trace the source of the infection to people who aren't vaccinated?
DEL RIO: Oh, very much so. If you look at the current cases, the current outbreaks that have occurred so far in our country, among those outbreaks, roughly 95% of those individuals are unvaccinated.
SIMON: Does this trace back to west Texas, or are there are several different areas of location, do you think?
DEL RIO: Well, there are now three outbreaks. One of them is in west Texas. One of them is in New Mexico. And the other ones are case occurring in different states and different jurisdictions, and they're happening, you know, across the nation. We're seeing cases as far north as Rhode Island, Pennsylvania, New York. We're seeing cases in Vermont. We're seeing cases in California. And really, just throughout the nation we're seeing cases.
SIMON: The cases you mentioned that have now moved north, are they somehow related to the cases in west Texas?
DEL RIO: No, Scott. The cases in New Mexico are related to west Texas, but many of the cases that we're seeing in other places are related to travel. And they may be travel that happens from, let's say, somewhere (ph) from New Mexico goes to California. But a lot of it is also international travel. The rates of vaccination in many other countries have dropped. And if somebody from (inaudible), let's say, flies into JFK, then that could lead to an outbreak in New York State.
SIMON: Are there are people who are vaccinated who should get revaccinated - I guess, a booster?
DEL RIO: Well, that's a question that I get to ask all the time, Scott, and let me try to make it simple. If you have received two doses of the MMR vaccine, which is the measles, mumps and rubella vaccine, or you have two doses of the MMRV vaccine, which is measles, mumps, rubella and varicella vaccine, you're good to go. The protection of - if you were born before 1957, when measles was widespread, and you likely got measles, you're well-protected, and the immunity lasts for many, many years. We know that the immunity to measles probably lasts over 100 years. So you don't need to worry about it. Now, if you are not sure - let's say you were born between 1963 and 1967, you may need a second dose of the measles vaccine. If you were born before 1989, it was only recommended you get one dose. So, you know, you usually - you may want to get a second dose, particularly if you're a health care worker or a college student or you're going to be in international travel. And if you were born after 1989, you probably got two doses of MMR, so you don't need to worry about it.
SIMON: What kind of people are most vulnerable, do you think? Is there an age, a location, anything like that?
DEL RIO: Well, again, you know, I want to emphasize, the most vulnerable individuals are those that have not been vaccinated. And if you look at the cases that have occurred so far in our country during this outbreak, roughly 80% of the cases are under the age of 19, and almost 40% of the cases are under the age of 5. And 95% of them are unvaccinated. So if you are a parent and you want to protect your children, what you need to do is vaccinate them. The measles vaccine is highly effective. It produces great protection, and the best thing you can do as a parent to protect your children is to vaccinate them.
SIMON: Are you concerned about cuts at the National Institute of Health?
DEL RIO: I'm concerned about cuts in anything related to health care, you know, whether it's the CDC, the FDA, the National Institutes of Health. They all have different missions. The NIH major mission is research. And, yes, any cuts there will decrease our nation's ability to advance science and to produce new science. And every day, you know, we forget that science has benefit so many of us.
I was talking to a patient earlier today who was cured from hepatitis C. The cure of hepatitis C is because of drugs that were developed through NIH-funded research. So he's very happy. He no longer has to worry about getting cirrhosis or liver cancer in the future. But I also worry about cuts to CDC. Public health is silent. You don't see it. Public health happens not only at CDC, but CDC gives the money to state and local health departments. And state and local health departments depend on that CDC funding. So it's going to impact every community in the U.S. And public health not only does vaccines, public health does cancer screening. Public health does nutritional assessment. Public health does so many other things that are useful to the community that, yes, I do worry about that.
SIMON: Dr. del Rio, I wonder what you say to people you encounter who may say, look, I don't think vaccines are safe.
DEL RIO: Well, the first thing I say to them is, I study vaccines. I work in infectious disease, and I know the data on how the vaccine studies are done. And all my children - they're now in their 30s - but my two children were fully vaccinated. And my grandchildren, I have five, and they're getting all their vaccines. If I thought vaccines weren't safe, do you think I would be vaccinating my kids or my grandchildren? So the first thing is that I believe vaccines are safe because otherwise I wouldn't be exposing my family to vaccines.
But the second thing I say is - I show them how vaccines have made dramatic impact in the life of individuals. Thanks to the polio vaccine, you no longer seeing polio. The main side effect of vaccine, Scott, is adults. If you vaccinate kids, they become adults. They don't die of preventable diseases.
SIMON: Dr. Carlos del Rio, professor of infectious diseases at the Emory University School of Medicine. Thanks so much for being with us.
DEL RIO: Delighted to be with you. Transcript provided by NPR, Copyright NPR.
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