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JUDY WOODRUFF: Now: the enormous benefits and significant perils of the recent upsurge in the availability of antibiotics around the world. Lisa Desjardins talks to science correspondent Miles O'Brien about the latest research. It's part of our weekly science series, the Leading Edge.
LISA DESJARDINS: Antibiotic resistance contributes to the death of 700,000 people around the world each year. Experts have predicted it will eclipse the number of people affected by cancer by 2050. One of the biggest causes is the overuse of antibiotics. On Monday, a group led by researchers from the Center for Disease Dynamics, Economics and Policies released a new study looking at the global consumption of antibiotics. They found the use of antibiotics worldwide has increased 65 percent from 2000 to 2015. Miles O'Brien is here to help us understand this latest study. Miles, first of all, just remind us, how does the overuse of antibiotics lead to these resistant diseases, sometimes called superbugs?
MILES O'BRIEN: Hello, Lisa. Yes, what happens is, antibiotics kill bacteria that make us sick. That's the simple explanation. But the bacteria over time evolve and develop an ability to survive the onslaught of the antibiotics. They, in essence, get smart. So, over time, bacteria survive that have resistance built in to the antibiotic themselves. Alexander Fleming, who invented penicillin, discovered penicillin, just before World War II, warned against its over use precisely because of this. Here's a few more words about how antibiotic resistance works from Dr. Helen Boucher of the Tufts University Medical Center.
DR.HELEN BOUCHER, Tufts University Medical Center: Resistance happens naturally. So, bacteria have various mechanisms to survive. And so if they're presented with an environment that is not so good, that is, there's an antibiotic
trying to break through their cell wall, they might build a stronger cell wall, or they might -- if there's an antibiotic coming in, they might pump it out. So they figure out ways to evade the effect of the antibiotic.
MILES O'BRIEN: So this study should give us quite a bit of pause, because it means, with more antibiotics in use, there are more bugs out there that develop the resistance, so-called superbugs. And now we have a much better global picture of the scope of the problem.
LISA DESJARDINS: That seems to be what's new here, is just the scope of this study, 76 countries' worth of data over 15 years. And where did they see the biggest increases in antibiotic use? Obviously, globally, but where specifically?
MILES O'BRIEN: So, Lisa, they found the biggest contributor to this problem is in low- to mid-income countries. Back in 2000, the usage of antibiotics in the lower- to mid-income countries vs. high-income countries was about equal. In 2015, the usage in those low- to mid-income countries doubled. So, that's a significant thing. That's good news for these countries. It means that GDP has improved, income is greater. They have access to these drugs. All these things are good. But the consequences of their overuse are just magnified.
Here is Eili Klein, who is the lead author of the study.
EILI KLEIN, Center for Disease Dynamics, Economics and Policy: Unlike, in high-income countries, where, when you go to the -- the primary barrier to getting antibiotics is, you have to go to the doctor to see -- to get a prescription. In many low- and middle-income countries, the barrier is the ability to afford the drugs. And so increased economic activity allows for increased ability to purchase all sorts of things, all types of goods, including antibiotics.
MILES O'BRIEN: OK, so the good news is that, in the higher-income countries, the increase in antibiotics use is only about 6 percent. So the knowledge of this problem and the efforts to guard against it may be having some effect. But this is a real conundrum for people in medicine, Lisa, because doctors, on an individual basis, they want to make us well, and they probably have about five minutes to diagnose us anyway. And so, in the individual case, it might make more sense to give that Z-Pak to that patient. But they also need to be thinking about society at large, and that's not an easy thing to weigh when you are looking at a patient who is sick and could use those antibiotics to feel better.
LISA DESJARDINS: And I think that's my biggest question here. The study really gives me and I think many of our viewers a lot of pause, but the incentives, as you say, all go the other way, toward prescribing antibiotics right now. Does this study have any recommendations for how to lower our use of antibiotics appropriately?
MILES O'BRIEN: You know, it's interesting. The recommendations were a little bit surprising to me. One of them was, we should be more focused on getting people vaccinated. Well, on the face of it, well, wait a minute, vaccines are for viruses, not bacteria, which is what we're talking about here. But what happens is, people get sick from viruses. Doctors mistakenly give those people antibiotics, which do nothing for viruses, and that just furthers the problem. Another thing that was discussed in the paper is the idea that, as these emerging nations grow, as cities become more populated, the issue of clean water and sanitation, the sources of many diarrheal diseases, need to be focused on a lot more, because that is ultimately why people seek out antibiotics in many cases. Here's more from Eili Klein.
EILI KLEIN: If you look at the history of the high-income countries in the 20th century, the primary driver that reduced infectious diseases was improvement in infrastructure, reducing -- eliminating bacteria and other diseases from the water. And so investments in infrastructure, investments in vaccines that can prevent diseases can be a really beneficial -- can be really beneficial to low- and middle-income countries, in terms of preventing disease and then reducing the need for antibiotics.
LISA DESJARDINS: There, Eili Klein laid out the hope, the prescription. But if society doesn't actually deal with this problem, what happens in the future if we do not lower our antibiotic consumption?
MILES O'BRIEN: Well, this is something we all really need to pay attention to, Lisa. The projections are, by 2030, our use of antibiotics, if nothing changes, will be triple what it is today. And what that means is, there are going to be many more antibiotics which become really just basically useless, more so-called superbugs out there. And we are facing the prospect of a post-antibiotic world. We take for granted these miracle drugs, which really since World War II have just dramatically changed medicine in ways that it would take too long to enumerate right now. But we could get back to a world, Lisa, if nothing is done, where something as simple as a cut or a blister could kill you, which is what the world was like before we had antibiotics. So it's time -- this is like a slow-motion train wreck. Researchers have been warning us all about it. And it kind of reminds me a little bit of climate change. But it's time to get a handle on this, because, right now, more than a half-million a year people globally are dying for lack of antibiotics.
LISA DESJARDINS: Something for each of us to think very carefully about. Miles O'Brien, thank you for bringing us this story.
MILES O'BRIEN: You're welcome, Lisa.
