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Fri January 13, 2012
New Tuberculosis Strain Thwarts All Antibiotics
IRA FLATOW, HOST:
This is SCIENCE FRIDAY. I'm Ira Flatow. We talk many times about the rise of drug-resistant bacteria, germs that resist most antibiotics, except for a precious few. A case in point is tuberculosis. But now comes word of a strain of TB that is totally drug-resistant, TDR TB as doctors are calling it. There are no second-choice antibiotics here. We simply have no drugs to fight this superbug. There are no weapons left. And it has now infected a dozen patients in India.
How did the strain originate? And if our drugs don't work anymore, what can doctors do, if anything, and what kind of threat does it - well, does it pose to us - the rest of the people around the world? Here to talk about it is Maryn McKenna. She is the author of "Superbug: The Fatal Menace of MRSA." She also writes the "Superbug" blog for Wired, where the story appeared. She joins us by phone. Welcome back to SCIENCE FRIDAY.
MARYN MCKENNA: Thank you.
FLATOW: Maryn, tell us about this - it sounds pretty scary this new superbug.
MCKENNA: You know, I have to say I find this chilling, and it's a little complicated. So the way this came to light is that immediately before Christmas, so almost everyone missed it at the time, including me, a couple of physicians in Mumbai wrote a letter to a medical journal describing four patients they have with what they called totally drug-resistant TB. Which means, as you said, none of the first-line drugs and none of the second-line drugs - that's more than a dozen drugs, altogether - nothing worked.
These people had - just were uncurable. The Indian media jumped on the story and got the hospital to admit that there are actually were 12 patients. They just happened to have complete histories for four. Now, over the next couple days, it turns out that TDR TB was actually seen before - in 2009 in 15 patients in Iran. I've spoken to the Iranian physicians. No one is quite sure what happened to those folks. And there were also two cases in Italy who both died in 2003.
So clearly, it's been popping up for a while, but it looks like this Indian cluster is the one that may be the most - the best documented, and it's certainly the one causing the most concern.
FLATOW: Maryn, do we know how this originated, or how it started?
MCKENNA: No. Unfortunately, that's the problem. So, you know, when we talk about antibiotic resistance, as you and I have talked before, we - there are all kinds of things that can contribute to that - misused of antibiotics; in agriculture, misused in, sort of, everyday medicine. What's going on here with this TB very clearly is that it's an artifact created by poor medical care and poor use of drugs. These people, in India at least, and certainly in the other cases, were not correctly diagnosed to start with.
They were given the wrong drugs. They weren't given the right length of drugs, and even at the best of times, MDR TB or highly resistant TB is difficult to treat. And they were sort of kind of natural laboratories for the emergence of the totally resistant strain.
FLATOW: So how fearful should we be, that this strain will permeate around the world?
MCKENNA: So, you know, this is a sort of plus-minus proposition. Because, on the one hand, it's really troubling to have something like this because we live in such a globalized society where people move back and forth from the industrialized world to the developing world through different economies. And diagnostic tools for TB are really not good. So, you might think that someone has everyday TB, and they might have a resistant form. The other side of that is that TB is not that easy to catch.
It's not like measles. You don't catch TB by just walking past someone on the street. You have to be in close contact with them. But I'll say the third thing that really makes my jaw drop is that, literally, as I was waiting for this phone line to come live, a bulletin moved across the wire that there are two more cases of TDR TB in another hospital in a different part of India. They were being held in confinement in the hospital, and one of them has gone missing.
FLATOW: One of the patients has gone missing?
MCKENNA: One of the patients has skipped out, probably understandably, because they - these drugs are not pleasant to take, and they cause a lot of side effects. You have to take them for a very long time. It's probably not very pleasant being treated as a public health criminal. So one of these patients has checked himself out of the hospital and disappeared.
FLATOW: So we don't know where that - an infectious patient with the strain of totally drug-resistant TB...
FLATOW: ...is missing. Wow. What would we do in this country? What are they doing in India, to find that person or to stop it from spreading?
MCKENNA: Well, I think the Indian government is really kind of struggling with this. And it must be said that the media in India have really jumped on this story and are really pushing it forward, which I think is just fantastic. Because, of course, and, you know, as has been seen in other countries with other profound infectious diseases, there's a lot of stigma associated with a situation like this where your country suddenly gets identified with the deadly disease. So the Indian media are pushing the government to try to articulate its plans. But the reality is, India is a pretty under-resourced society when it comes particularly to health care because of the size of its population and the differential between the rich and the poor. It does not have the diagnostic tools that are needed. It's actually quite difficult to diagnose resistant TB, as opposed to plain TB.
FLATOW: So what do you do to treat these people? Are you going to do - or is it back to the old sanitarium, pre-antibiotic days? You put people out, isolate them, quarantine them and hope they get better?
MCKENNA: Well, if you think back a couple of years ago, when people started to be concerned about MDRTB, that's TB resistant just the first-line drugs, there were a couple of cases that came into the United States and public health authorities held them, essentially, in isolation. The - what's suppose to happen is that until you are deemed non-infectious while you've been in drug treatment, if you have one of these highly infectious, highly-resistant forms, you are supposed to be confined in some manner. But, you know, if you ask a public health person, do we have enough isolation rooms and hospitals in this country to contain a major epidemic, we already know from worrying about highly-infectious flu that we don't have enough isolation rooms. We certainly don't have enough to contain a major TB epidemic.
FLATOW: So everybody's going to be watching to see if this spreads. And in the meantime, the Indian government will be looking for this missing patient.
MCKENNA: I think that people are really concerned about what happens next. Because as one of the physicians who brought this to light to start with a couple of days ago, admitted what they have identified is just the tip of the iceberg. And really, no one is sure how big the rest of that iceberg is.
FLATOW: Let me see if I can get a quick question in from a listener. Let's go to Jared in Ann Arbor, Michigan. Hi, Jared.
JARED: Hi. Thank you for taking my call.
JARED: I watched a documentary some time ago about the Soviet bacteriophage program, where they cultured different bacteriophages that would specifically attack different disease-causing bacteria. It appeared that that program really shutdown with the fall of the Soviet Union. But I was wondering if that technology still offers any promise for treatment.
MCKENNA: So, that's a really interesting question. A couple of things within that, the first is that the phage program did not completely shut down, though it ceased to be state-supported. And I believe there's still a phage program in the state of Georgia - not the state of Georgia I'm sitting in, but the state of Georgia in the former Soviet Union. But whether phages are effective against tuberculosis is something I really know nothing about.
FLATOW: Yeah. But it's an interesting question, Jared, about using phages, because there's a phage for every kind of bacteria, isn't there?
JARED: That's what the documentary indicated...
JARED: ...and I was wondering if that was a possibility in this case.
FLATOW: All right. That's an interesting possibility. Thanks for calling. 1-800-989-8255. So how do we wrap up this story? Is this a hopeful story, Maryn, or is it - are we just fearful now?
MCKENNA: I think it's reasonable to be fearful. I don't think we should be panicked. I think we should be paying attention to the lessons that are embedded within this story. There are a couple of them. The first is the - sort of one of my favorite themes, which is where are the new drugs? Because the reason that we're so scared about highly drug-resistant TB is because there's no new drug coming along. The drugs that we rely on for TB control, in fact, a lot of bacterial control these days are about 50 years old, because it's not cost-effective for pharmaceutical companies to make antibiotics.
The second is we have to be aware that we need much better diagnostic tools, you know. It can take weeks to grow TB out in culture to figure out if it's susceptible. But there are some new diagnostic techniques, molecular diagnostic techniques that could help and make that faster if developing world economies could afford them.
And the third is we just have to be aware that, really, we're all vulnerable at any time. Borders don't protect us. These kind of diseases move back and forth across borders without being detected, and we're really only - as so many health - public health authorities always say, we're only a plane ride away from anything.
FLATOW: All right. Thank you, Maryn.
MCKENNA: Thank you.
FLATOW: Maryn McKenna is author of "Superbug: The Fatal Menace of MRSA." She also writes the Superbug blog for Wired, where you can find this story, and it first appeared. And she joined us by phone. Transcript provided by NPR, Copyright National Public Radio.