More Science Talk
October 24, 2007 -- Good Germs, Bad Germs
Welcome to Science Talk, the weekly podcast of Scientific American for the seven days starting October 24th. I am Steve Mirsky. This week on the podcast: Germs. We'll talk with journalist, Jessica Snyder Sachs, author of the new book, Good Germs, Bad Germs. Plus, we'll test your knowledge about some recent science in the news. Jessica Snyder Sachs is a contributing editor of Popular Science and Parenting magazines. She has been adjunct faculty in journalism at Fordham, N.Y.U. and Kean Universities. Her first book was called, Corpse—more on that later. The new germ book is subtitled Health and Survival in a Bacterial World. I called Sachs October 18th at her home in Maple Wood, New Jersey.
Steve: Hi Jessica. Good to talk to you.
Jessica: Hey Steve. Good to be with you.
Steve: You've got this book out about germs, about bacteria and our relationships with them; the timing of our conversation is really good because we set this up many weeks ago but the staph infection news is very hot right now. What's going on with MRSA? First of all, what is MRSA? What does that stand for?
Jessica: It stands for methicillin-resistant Staph aureus. Methicillin is a just one class of antibiotics though that these strains of staph are resistant to, so it's kind of a catch phrase for most types of drug-resistant staph.
Steve: And this disease has just killed two young people. That's been in the news, just in the last couple of days as we are speaking. And the report that came out today or yesterday was that they've realized that perhaps 20,000 people were killed by it in the last year in the U.S.
Jessica: Absolutely! And the news is really, the media has caught on. This has been a big problem here for years. In Canada and in the U.K., they've been screaming about it, but here in the United States, where actually hospital-bred MRSA started, it's been kept under the rug—and partly this is due to our hospitals don't have to report infection and nobody wants to admit they have a
n MRSA problem and scare their patients away to another hospital that, who knows, might have a worse MRSA problem, so its been a dirty secret.
Steve: A dirty secret is right, I mean, you know, that's medical malpractice. That's negligence. If you've got this, you have an epidemic actually, I mean, if 20,000 people were dying of something else, in the country and it was being hush-hushed, there would be some pretty big outrage out there.
Jessica: Well, in the medical journals, they are trying to get a handle on this, but what's so tough is, and again it circles back to the hospitals don't report this stuff and it's nothing new. In the book, I talk about way back in the 50s, the first super staph, the first supergerm; same situation: no hospital wanted to admit they had a problem and it was killing babies. These were some of the few years that the death rate in our country spiked up in the 20th century, because this staph back in the 50s was so bad, but nobody wanted to admit they had a problem and the way things are set up in our country, hospitals can voluntarily report these things to the CDC, but the CDC is honor bound not to identify the hospital. So, CDC for the last four or five years has been trying to get a handle on this, trying to see what's happening and so in the medical journals, it really, you know, the scientists really are talking about, "Hey we've got a problem here, don't know what we want to do with this." But it hasn't really caught the attention of the general media, like it has, say, in Canada and in the U.K. And I'm sorry to say MRSA isn't the only really scary hospital bug that's killing people who are going in, even for ordinary procedures.
Steve: It's ironic, but perhaps the death of this one person or two people in the last week may be more of an initiator of action than the death of 20,000 people.
Jessica: Well, you know, you are in the journalism business, and you know how we can feed on ourselves. And once something finally breaks through into the news, then there is that the momentum build; maybe it will get some laws into place where we are tracking these things more carefully, we are finding out what's going on and what is where and that puts pressure on everybody including the hospital to really bring their MRSA rates down.
Steve: You know...
Jessica: …It's not easy. Nobody is saying it's easy.
Steve: I want to get to the book, but you mentioned other infections in hospital settings that are as bad.
Jessica: Right! There is another real bad one these days, Clostridium difficile. The C. difficile has been around for awhile, but in the last five to 10 years there is a really nasty hospital strain that is very toxic. It's an intestinal bug—you hardly ever pick it up unless you are on antibiotics. The antibiotics wipe out your good bacteria in your gut and C. difficile can move in and this new strain can kill people very rapidly. And I myself know somebody, a friend of mine, whose mother went in for a routine procedure, she picked up C. difficile and she died, and again it's one that's killing a lot of people.
Steve: You have the quote in your book, and it's oft repeated: "A hospital is no place for a sick person."
Jessica: No, it's true, especially when you are in on antibiotics and some of the infection control people, what they are learning is, the faster you can get hospital patients off of antibiotics, once you've got the bad bug, you know—of course antibiotics are lifesaving medicines, but you don't want to keep people on them longer than necessary, because it knocks back their good bacteria and it leaves them wide open for the drug-resistant supergerms.
Steve: Right! And let's go to the book. The book is called Good Germs, Bad Germs and we are so used to living in a culture, pardon the (unclear 6:34), but a culture of antibiotics, and people might not appreciate that there is a whole ecosystem in and on your body and antibiotics, you know, they are of course, there are miracle drugs like penicillin that have saved countless numbers of people. But at the same time, there is this ecosystem that's in a delicate balance that itself may be saving countless numbers of people as well.
Jessica: Absolutely! It's our first and maybe our most important bulwark against disease. You know, these are the microbes that have evolved to get along with us and they crowd out and keep at bay the ones who would do us harm.
Steve: So one of the ways to deal with harmful bacteria is to make sure that you have a lot of good bacteria in and on you to outcompete the harmful bacteria.
Steve: As opposed to antibiotics, we now have probiotics. Why don't you talk about that for a little bit?
Jessica: Right! Now, there's been lots of good research showing beneficial effects of probiotics. Now I hasten to add, the stuff that we eat down in our yogurt or even pop in probiotic pills, that doesn't really take up a permanent residence in us—or very few of them do. A small number of them actually do, but they have some very nice effects on the immune system and they can't temporarily keep bad things like salmonella at bay, but we are all colonized really very soon after birth and so this ecosystem as you say developed and we want to be careful when we use antibiotics, not to use them in a "What can it hurt?" fashion, because the side effects of antibiotics are often associated with the destruction of the good germs.
Steve: Right! I'm sure you are familiar with Dr. Relman's work out in California.
Steve: Right! This new study that came out in the spring, we've talked about it on a previous episode, but it's probably worth discussing again, about the newly colonized babies. They looked at the stools from the kids.
Jessica: Well of course, David Relman has not been the first one to do this. It's been, you know, people have been looking at the stools of kids for all about 80 years now, and what David brought to it is he's, you know, DNA fingerprinting them. So, he's picking up a lot of the bacteria that you can't culture, you know, so many of the bacteria in our bodies won't live in a Petri dish. We think of E. coli as the big intestinal bacteria. It is really a small player, but we know it so well because it will grow for us in a Petri dish. Most of the bugs in our intestine, you know, the slightest wisp of oxygen kills them, so now David and other people—like Jeffrey Gordon at Washington University—they are taking, you know, DNA fingerprints and saying, "Hey, we've got a lot more in there than we've ever grown in a Petri dish; look at all these DNA fingerprints." So it's a very, very rich ecosystem in there.
Steve: We've got a lot more in there and each of us has a unique assembly of them.
Jessica: Right! There's, you know, there is certain common ones that most people have, but you are absolutely right. There is such a variety in there that that no two people have exactly the same bacteria.
Steve: And in a sense, I mean, the more you look into this, the more you get the feeling that you know, you are not really an individual, you are living in some kind of an arrangement with these billions of other organisms.
Jessica: Exactly! Joshua Lederberg, Nobel Prize winner and a professor emeritus at Rockefeller University, he coined the term microbiomeand that's [it] exactly, he's pointing that we are not a single organism, we are an amalgam of organisms and the often quoted factoid is that, you know, [the] human body contains 10 times more bacterial cells than human cells, of course, they are so very much smaller than ours, but still their genes contribute a lot to the trait that make us humans.
Steve: What is that you say somewhere in the book that you know some people have toyed with the idea that we are just devices that bacteria have come up with to carry them around.
Jessica: Right! I mean the bacteria were here long before we came on this thing, you know, they have also heard it as said by scientists
or [that] we are just a little blip on their light stand, you know, if we do ourselves in, they're are just gonna keep on going.
Steve: What made you want to write an entire book about the bacteria that we live with?
Jessica: Well, in part it's kind of flipped out of the first book, I wrote
was called, Corpse: Nature, Forensics, and the Struggle to Pinpoint Time of Death—and that was about the ecosystem of the human body after death and how forensic scientists could read those natural clues, the bugs and the plants to determine time of death and the flip side of that is the amazing ecosystem of the human body during life and that's what we are with this tremendous landscape for bacteria to colonize, soon after we emerge from the womb.
Steve: You know, your previous book accounts for the speaking engagement that I found that you had. I found it online, which was the most unusual one I've ever seen for a science journalist and that was at, last year's New Jersey Funeral Director's Association Convention.
Jessica: Exactly! Yes that book produced some very strange speaking arrangements. I was also kept getting invited to romance writer's conventions, of all things, because they needed to know, you know, when they knocked off the bad guy (laughs) or the victim, what would happen. You know, they wanted to be able to scribe it. You know, what would happen to the body?
Steve: I see.
Jessica: So, yes (laughs) it led to some very strange speaking engagements.
Steve: That's pretty interesting. As you did the research for this book…
Steve: Give us one or two of the things that you learned that because you know, you've been a science journalist for a long time, you knew a lot about bacteria going in? Well, what didn't you know that you learned that really surprised you?
Jessica: Well, some of the most exciting stuff that's coming out of immunology today is for the last hundred years, we've focused on, of course, how bacteria makes us sick and how our immune system fights them. Even today, you look in an immunology textbook and it will say we don't know why the human body tolerates all the bacteria in our intestines and on our skin. Why doesn't it attack them? Well, immunologists are really working out why that is, and there is this conversation going on back and forth between the bacteria that are in our bodies and in our lives and our immune system and it's not just an attack thing. Bacteria, harmless bacteria, not the ones that make us sick, but the abundance of harmless bacteria in our bodies and in our environment have a very calming effect on our immune system and they are really showing exactly how that works, how the bacteria in our immune system interacts—and that really explains the epidemic of inflammatory diseases that have come with modern sanitation and antibiotics. Don't get me wrong—modern sanitation has saved more lives than probably any other advance in human history.
Jessica: But there was a trade-off. You know, we suddenly distanced ourselves from this ocean of bacteria, you know. We used to live, you know, sleep on the floor and pull our food right from the ground and store it crudely, and had all these harmless bacteria flowing through our bodies. So, it's fascinating.
Steve: So, what can we do to be less sanitary and healthier at the same time?
Jessica: Right! A good question and a tricky one. We certainly don't want to go back to the bad old days of cholera epidemic[s] or typhoid. In the summer I live on an island where we don't have public sanitation, and you bet I boil my water because along with all the good bacteria there are also some parasites in the water and I don't want those, so it's tricky. How do we add back in the good bacteria, the calming bacteria? Probiotics might be part of that and now they are finally getting studied and some more powerful probiotics or even vaccines that contain killed bacteria are being developed that can calm the immune system and may be finally give us cures for things like allergies and asthma and maybe even some autoimmune diseases.
Steve: I've become a real fan of hand washing. I haven't gotten sick in about three years, ever since I started hand washing a lot. But is there anything I shouldn't do that, you know—should I dust less? I mean it would be pretty impossible for me to dust less, but you know what I am saying.
Jessica: Right! Even though
that this is all called the hygiene hypothesis, it really doesn't come down to housekeeping or even, you know, how clean you are; definitely in cold and flu season, I think, hand washing has its place. The way from all the researchers I talked to, I will advise again antibacterial cleansers that contain triclosan and triclocarban, because they have been found to act like antibiotics. Plus, they don't prevent infections any better than ordinary soap and water, so why risk producing antibiotic resistance, if good old-fashioned soap and water will do the trick?
Steve: Right! And we should point out any time you are using an antibiotic you are driving evolution, you're selecting for the strains of bacteria that are resistant and they are going to grow out and predominate in the population after that.
Jessica: Exactly! You said you're selecting for them.
Steve: Yeah! You're actually going out of your way to create a problem.
Jessica: All right, so antibiotics are wonderful life-saving medicines, but we can't be using them with this, "Uh! What can it hurt attitude!" because there are serious consequences to their use and overuse.
Steve: One of the interesting things that you mentioned in the book is this idea of creating antibiotics with on and off switches, so that we can administer them but the individual entities that pass through us won't just spill out into the ecosystem where they can then still be active.
Jessica: Right! And scientists—environmental engineers—in the last two years have been tracking both antibiotics and antibiotic-resistant genes. They've become pervasive pollutants in our waterways, in our soil, and people need to remember or learn that bacteria will trade genes very easily. So, yes, when we shed antibiotic-resistant genes from the bacteria in our intestines into our sewage, it ends up in our waterways, on our crops, it is becoming a pervasive pollutant and it hopes to explain perhaps why bugs are becoming more drug-resistant
more fast[er] than ever before.
Steve: Yeah! And with the potential for the on-off switches in the antibiotics, the stuff that would get out into the environment would basically be inert and wouldn't have that kind of a cascading effect.
Jessica: Right! And then there is also the advantage of doctors more carefully choosing their antibiotic, because they are not [all] the same. Some are more sniper bullets that are more likely to take out just the one bacteria or one class of bacteria; other[s] are big guns, the broad-spectrum antibiotics that will just pretty much wipe out everything.
Steve: Right! And we have to stop prescribing—I was going to say subscribing, but that's because I work at the magazines—we have to stop prescribing antibiotics for viral diseases.
Jessica: Right, right! They don't do anything against colds or flu and there is also much controversy about using them preventively. I know when my daughter was, you know, in preschool then it was the fashion for pediatricians to prescribe, "Oh! Just give her amoxicillin everyday to prevent ear infection." We now know that is a really bad idea.
Steve: Sure, so you just mentioned flu. You had an op-ed piece in the <i>New York Times</i> last week connecting flu and the resistant staph infections.
Jessica: Right! The new strains of MRSA that are circulating in our community; these are more community strains than hospital strains, so now they are getting into the hospitals as well. They have some nasty toxin genes that are on the heels of a respiratory infection—especially the flu—[that] can produce a very deadly pneumonia and probably the best way to protect ourselves from MRSA pneumonia is to get a flu shot.
Steve: So you get two for the price of one there.
Jessica: Yeah! There you go and thankfully MRSA pneumonia is still rare, I mean not super rare—as we've seen in the media—and it is nothing new, people die of it every year but it is the one way you can reduce your risk, because we can't get rid of staph; about a third of us carry one kind of staph or another without even knowing it at any time. We really can't eradicate it, but we can protect ourselves by getting a flu shot and reducing the risk of that staph that is around, when we can't avoid [it], [that] it will give us something like a deadly pneumonia.
Steve: Yeah! I mean my own brother just banged his leg and had an open cut there and he got a staph infection because the staph is living on us naturally a lot of the time.
Jessica: Right! It's one of our most, probably the most problematic of our resident microbes and, as I mentioned, at any one time about a third of us is carrying it around.
Steve: So again, the book is Good Germs, Bad Germs and the blog which is at jessicasachs.com is where you can read the book and then the blog is sort of an extension of the book that will address whatever happens to be the newest developments in this field.
Jessica: Right! Try to keep up on it, there is so much going on.
Steve: Very interesting talking to you. Thanks very much Jessica.
Jessica: Thanks Steve.
Steve: You can find links to a lot of Jessica's magazine articles at her Web site, again it is www.jessicasachs.com.
Now it's time to play TOTALL…….Y BOGUS. Here are four science stories, only three are true. See if you know which story is TOTALL…….Y BOGUS.
Story number 1: Fires in the U.S. release about 30 percent as much mercury as do the nation's industries.
Story number 2: Mice that spent 15 minutes a day on a vibrating platform were leaner than mice put on a stationary platform.
Story number 3: In a speech, Nobel laureate James Watson of DNA fame said that the single best thing about DNA was the evidence it provides for the interconnectedness of all humanity.
And story number 4: Just a fast glance at the faces of candidates for an election is enough for most people to pick the eventual winner.
Time is up.
Story number 1 is true. Fires do release about 30 percent as much mercury into the atmosphere as industrial sources do. That is according to researchers at the National Center for Atmospheric Research who published in the online edition of the journal, Environmental Science and Technology. Some of the mercury in the fires also came from industry. Initially, it settles into soil and plants and then gets released all at once in the fires. And once it is airborne, the mercury can travel downwind and contaminate waterways and natural areas, which is bad.
Story number 2 is true. The mice on the vibrating platform indeed had 30 percent less fat around their middle[s] than the mice on motionless platforms. The lean mice didn't weigh less, they just had less fat. For more info, check out the October 23rd episode of the daily SciAm podcast 60-Second Science.
And story number 4 is true. Princeton researchers showed study subjects pictures of people for just a split second. The people in the photos were in fact candidates in governor and senate races in other parts of the country. The subjects were told only to pick the person who looked more competent and didn't know anything about elections; and they wound up picking up the actual winner of the election about 70 percent of the time. The study appeared in the Proceedings of the Natural Academy of Sciences. Our ability to judge competence may be incompetent.
All of which means that story number 3 about Jim Watson waxing rhapsodic about DNA and humanity is TOTALL…….Y BOGUS. Because Watson in fact made some pretty stupid comments about Africans having lower intelligence than Europeans. He later said, "I cannot understand how I could have said what I am quoted as having said."Watson knows a lot about some things, he also knows very little about other things that he nevertheless expounds upon. For example, in 1998 Watson said that cancer would be cured in two years. According to thousands of reports just issued in hundreds of journals there is still cancer. For more on Watson, check out "News Bytes of the Week" at the Scientific American Web site.
Well that's it for this edition of the weekly SciAm podcast. Check out numerous features at our Web site, including the "Weird Science," the photo gallery and the latest science news, all at www.SciAm.com, and you can write to us at podcast@SciAm.com. For Science Talk, the weekly podcast of Scientific American, I am Steve Mirsky. Thanks for clicking on us.
Web sites mentioned on this podcast include: www.jessicasachs.com.