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roundtable: the evolving enemy Watch Show 4:
"The Evolutionary Arms Race"
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Select a question:
How concerned should we be about becoming infected with resistant bacteria from foods like chicken, beef, and even aqua-cultured fish that may have been grown on diets treated with antibiotics? Will eating less of these foods, perhaps by switching to "organic" chicken, reduce our risk, and do vegetarians have a reduced risk for this reason?
If the use of antibiotics in a widespread fashion at low doses in agriculture, particularly in the raising of animals, is so common and yet so potentially dangerous from the standpoint of evolution of resistance, why is it still the practice? What are the costs and benefits of this practice?
Several people have submitted questions not about antibiotics, but about all of the liquid soaps that are now for sale in supermarkets that are labeled "antibacterial." Do these work like antibiotics in causing further resistance? If so, how, and if not, how is their action on bacteria different than just plain soap?
Americans now seem to be getting fanatic about sterility, and people are trying to raise their children in an almost "germ-free" environment. We have a question from a woman who says that she has several friends, young mothers, generally, who seem to overuse antibacterial products. She asks: Is it not true that the presence of some "germs" in moderation is actually good for the development of our immune system?
In one of the programs in the Evolution broadcast series, there was the story of the leafcutter ants that culture Streptomyces bacteria on their bodies and seem to use those bacteria to apply antibiotics to keep their fungal farms parasite free. This has been inferred to mean that somehow the Streptomyces and the antibiotics they produce have been evolving with the enemy, and this is a kind of use that appears to have been going on for 15 million years without permanent resistance being developed. Is there anything we can do to put ourselves in that situation versus the more static situation we're in now?
Could you give an explicit description of how evolutionary theory informs integrated pest management? I think the cross-fertilization here between bacteria and antibiotic resistance and agricultural pests and insecticide resistance is very interesting, and I don't think many people make that connection.
Some physicians, who are quite impassioned, say they would like to prescribe fewer antibiotics, but their patients demand them. Since in effect they cannot be absolutely positive there isn't a bacterium involved, when, say, a parent brings in a young child who is ill, and they can't be absolutely certain that there won't be bacterial complications as a result of a viral illness, they would like to know how the public will be educated and who is going to take on the job, so that patients will basically get off the doctors' backs and let their colds run their course.
Another part of that question is that doctors are afraid of being sued if they don't prescribe an antibiotic and a bacterial infection does develop. So from the medical perspective of overuse of antibiotics, how might we address this basic problem in the interface between healthcare providers and the consuming public?
   

 

Q: Some physicians, who are quite impassioned, say they would like to prescribe fewer antibiotics, but their patients demand them. Since in effect they cannot be absolutely positive there isn't a bacterium involved, when, say, a parent brings in a young child who is ill, and they can't be absolutely certain that there won't be bacterial complications as a result of a viral illness, they would like to know how the public will be educated and who is going to take on the job, so that patients will basically get off the doctors' backs and let their colds run their course.
Another part of that question is that doctors are afraid of being sued if they don't prescribe an antibiotic and a bacterial infection does develop. So from the medical perspective of overuse of antibiotics, how might we address this basic problem in the interface between healthcare providers and the consuming public?
Panelist Responses: < back to intro page
Stuart Levy
I am a physician, my father's a physician -- he's probably more of a physician than I am, since I really deal with tertiary care in a hospital, and my father actually takes care of patients at home, which I think is more representative of what's happening out there. It is difficult, there's no question. But I'm delighted to see that the American Academy of Pediatrics has come out with the statement that, in fact, one can wait 24 to 36 to 48 hours with most infections and not do any harm. And it's basically what we were taught in medical school: to give the prescription, but to wait -- in those days you had to wait a day or so while a sample was cultured to see if you had, for example, a strep infection -- and then say to the patient, when the results of the culture were known, either, Fill the prescription, or, Tear it up.

I think in the case of the ear infections, it's a case of asking, How is the child doing? The Europeans have it down to a science; they virtually do not give an antibiotic when they first see the patient, unless they see pus and all sorts of signs of a real infection. But they assume that if there is one, if it's viral it will cure itself, and if it's bacterial, it has a one in two chance of curing itself. So that leaves you with a small number of patients, about five percent, that actually need antibiotics.

That being said, the much stronger problem I think that physicians worry about is the litigation. And I think that we're making inroads by having the professional societies come out to say, "This is what we think is the correct practice." Clearly, the sooner we get rapid diagnostics that will tell us whether an infection is viral or bacterial, the better, because then we will know what to do. But I think the patient-physician relationship is critically important, so that the physician can say, Look, there's a downside to giving antibiotics, we talked about the hygiene hypothesis, we talked about drug resistance. We can wait on this. I've seen the child, and I'd say let's wait 24, 36 hours, and then let's see how the child is doing.

The Alliance for Prudent Use of Antibiotics, which has a Web site for consumers at APUA.org, also has consumer education materials that we have given out to large numbers of physicians to give to their patients that says this is what an antibiotic is, this is what should be done with it. The Centers for Disease Control have material, as well.

I think there has to be, to help the physician, a strong educational campaign for the consumer, so that the dialogue is equal. Then the physician isn't just speaking from the physician's knowledge, but the consumer also has an information base that makes them secure in accepting -- which I think they should -- the doctor's advice that we aren't going to start with an antibiotic, we're going to start with symptomatic treatment.
Tamar Barlam
There's so many points that could be made about this, but first, I think the patients demand it because they haven't been given good information as to why they shouldn't. And the Centers for Disease Control and many local health departments have started education projects including prescription pads that say, "You do not need an antibiotic." The patients and their parents have been very responsive to this in general, and it's really a lack of explaining and taking time, in many cases, to educate patients, that creates this demand.

I think another thing that creates the demand is if it's projected as a community or environmental or rational problem, it's hard for a parent to worry about that when their child is not feeling well. So I think that a point should be made to the parents, or the patient, if it's an adult, that you are putting yourself at risk by taking too many antibiotics. You are causing resistant bacteria so that when you really need it you might find it much harder to treat a worse infection.

There's been a couple of recent interesting papers. In adults with sore throat, three-quarters get an antibiotic, even though statistically probably less than a quarter actually have streptococcal infection. Things that would help there would be rapid testing, for example, but also explaining the situation to them. And they will not have a dire consequence if they wait a day or two for the culture to come back and then take treatment.

If in conditions where the harm of waiting to give an antibiotic is minimal -- sore throats, ear infections, sinus -- if you just wait, the vast, vast majority of patients might have some annoyance, might have symptoms that they perceive are persisting because they didn't get the antibiotics. But these are not life-threatening infections, so although the fear of being sued is indeed in there, part of the problem is also that neither the doctor nor the patient wants the inconvenience of having to go back for a second visit, and I think we have to look at that.

But if you look at the money wasted on antibiotics, by patients and the healthcare system, if we just put a fraction of that money into educational programs and outreach for the physicians and for people going to the doctor's office, I think that we could really make a major impact on this problem.
George Beran
I would like to add a comment. Let us realize that what you have been sharing here in terms of pediatric medicine and human medicine has the same application in pet animal medicine. We have about 115 million dogs and cats in this country, more than we have children. We face exactly the same thing -- in that the pet owners want the antibiotics -- that you face in human medicine, and we have the additional concern in treating animals that the bacteria, the infection that we are attempting to treat may be transmissible to people, and if we delay the use of antibiotics or other antimicrobial drugs, that we may be posing a problem of transmission from the animals to the people.
Stephen Palumbi
I think one of the good things about all these comments is that they talk about the problem not as a single one, not the physician's problem or the patient's problem, but in terms of the interaction between them, and it's that interaction which is key to solving the problem. One of the questions I'd ask Tamar is on the study of particularly adult infections and antibiotic use. How often is a physician prescribing an antibiotic without even seeing the patient? I know that that happens. It is not the way it should be.
Tamar Barlam
It's very sad how often that does happen.
Stephen Palumbi
And you cannot have any communication between doctor and patient when somebody just calls up and says, I have a runny nose and a sore throat, and the doctor prescribes antibiotics. So another issue is to encourage the interaction between patient and physician so that a health strategy can be devised, and that health strategy can include the consideration of these evolutionary potentials. And it isn't just the evolutionary potentials that would benefit from that interaction. People's health in general would also benefit from an interaction between themselves and their physician.

So one of the proposals might be in fact that people do sit and talk with their doctors about what options they have. That's the kind of thing that is more and more difficult to find in our healthcare system, and I wonder whether that's one of the dangers that we're facing -- a lack of that communication between physician and patient.
Tamar Barlam
I think that's definitely a factor. I think physicians are under pressure to see X number of patients per hour, make X number of phone calls in order to be financially solvent or meet their quota for their health organization. And I think our emphasis has just shifted. If there is a good doctor/patient relationship, better communication, patients will be much more willing to listen about not taking an antibiotic, much less likely to sue if there's a problem. If you actually sit down and say, You might not feel better in a day or two, and then this is what we're going to do, I think that there will be a lot fewer problems.

And I think that actually for the patients, the inconvenience of having to get hold of your doctor again and to follow up again, and for the physicians the pressure to just keep things going, as it were, and minimize repeat office visits, is great. It's the wrong emphasis for us to have right now, because we are having short-term reactions to a long-term problem that has been created.
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