modern meat
home
is your meat safe?
inspection
industrial meat
discussion
photo of morrisinterview: dr. glenn morris

Describe E. coli.

E. coli is a very common bacterial species. It's one of the most common bacteria in your intestinal tract. However, there's certain groups of E. coli, a certain subset of E. coli that carries some genes that make it particularly nasty. Most of these strains fall under a group that we call E. coli O157:H7.

What's nasty about it?

They are particularly nasty because they produce certain types of toxins that can cause pretty bad things to happen in humans. It can cause kidney failure, it can do bad things to your red blood cells. If you get infected with E. coli O157:H7, there is a possibility that you could develop what we call hemolytic uremic syndrome, which can be, in some instances, a fatal illness.

People talk about pathogens and microorganisms. What do they mean?

Most of the bacteria in the world are relatively innocuous so far as we humans are concerned. They cover our skin, they fill up our intestinal tract. They generally don't do us any harm. However, there are certain bacteria that, because of certain genetic capabilities or the ways in which they have evolved, have the ability to cause disease. Those are the ones we call pathogens. We say they're "pathogenic," they cause disease in humans.


Glenn Morris is a professor and chair of the department of epidemiology and preventive medicine at the University of Maryland Medical School. He was part of the USDA team that proposed stricter meat and poultry inspection regulations after the E. coli outbreak in the Pacific Northwest in 1993. He believes that the industrialization of meat production has led to a greater chance for the spread of pathogens like E. coli. In this interview, he describes the most common disease-causing bacteria found in food and new techniques for tracking and controlling food-borne illness.

We really don't know how much antibiotic is being used in agriculture in this country. And that's kind of scary.

The ones we worry about most, in terms of the meat industry would be salmonella, campylobacter and E. coli O157:H7. E. coli O157:H7 tends to be a particular problem in terms of red meat, particularly hamburger.

Anywhere from 1-3 percent of cattle may be carrying E. coli O157:H7 in their intestinal tract. If great care is taken when the cow is slaughtered, there shouldn't be a problem. But even when care is taken, sometimes there's the opportunity for contamination from bacteria that are present in the intestinal tract getting onto the meat.

What about listeria?

Listeria is actually more of a problem for prepared meats. Salmonella, campylobacter, and E. coli O157:H7 live in the intestinal tract of animals, and consequently, they tend to get on meat or chicken during the slaughter process. In contrast, listeria is an environmental microorganism. It lives in plants. It lives in water droplets on the ceiling and in the drains on the floor. It tends to cause problems in processing plants where foods come through that are not subsequently re-cooked. For example, deli meats or hot dogs, or cheeses that are not pasteurized.

In the past, our inspection system relied on somebody really looking at every carcass. Is that a good way to inspect meat?

The core inspection system that we had prior to 1995 was based on what we call organoleptic inspection, inspection that you can do with your senses, your hands and your eyes and your smell. This was a system that was actually developed back in 1906 in response to problems with dead and diseased or dying animals coming into the food supply. It was a very effective system for getting rid of diseased and dying or dead animals, because you could see that the animal was dead before it came in for slaughter. The problem is that things change, and in the 1990s, the problem with our food supply was not diseased, dead, or dying animals coming in for slaughter. The problem was contamination by microbes, by bacteria, such as E. coli O157:H7. You can't see bacteria.

What is it about the modern farming and meat production techniques that makes E. coli a bigger problem?

E. coli is an organism that has taken advantage of modern farming techniques. What we've seen is a significant reduction in the number of farms, and an increase in the size of feed lots. Under these conditions, there's a greater chance for passing the microorganism back and forth. Animals are transported much longer distances to come to slaughter. All of this contributes to spread of the microorganism such as E. coli O157:H7. Perhaps more critical, however, have been the changes in the ways in which we handle things like ground beef.

It used to be that hamburger that you bought in the supermarket was probably ground in the back of your own supermarket, from the scraps left over from the butcher's cuts that day. Nowadays, however, hamburger is more frequently made in large plants, where they work, literally, in ton lots, or multi-ton lots, with huge grinders moving large volumes of ground beef through at a time. That provides a very nice opportunity for cross-contamination.

The thing about E. coli O157:H7 is that it doesn't take much to cause illness. Only a couple of microorganisms, a couple of bacteria are enough to cause potentially fatal disease in humans. Consequently, if you have a carcass that comes in that was heavily contaminated, or even moderately contaminated with E. coli O157:H7, and you toss it into the grinder along with meat from all sorts of other locations, it all gets mixed up together, contaminating thousands of pounds of hamburger.

Can you explain the controversy around feeding antibiotics to the animals we eat?

For example, if you treat chickens with bacteria with antibiotics over a long enough period of time, the bacteria will develop reistance. What you run into are problems with resistant microorganisms that may then colonize the chickens. What tends to happen in a chicken house is that when you get one flock that you've treated with antibiotics and maybe developed a few resistant organisms, those resistant organisms are in the fecal material that gets down into the litter. When you introduce a new flock, it's going to pick at the litter and pick up those resistant organisms, and so potentially one dose of antibiotics may result in successive generations of chickens coming through that chicken house carrying a resistant microorganism.

What's wrong with that?

The problem is, if a resistant microorganism is something like salmonella or campylobacter, when we humans contract the illness from eating chicken that's not properly cooked or from a variety of other reasons, we may not respond to antibiotic treatment. One of the things that's worried us most recently has been the increase in the percentage of campylobacter isolate that are susceptible to Ciprofloxacin, which is the drug we use or have used in the past for treating campylobacter of gastroenteritis.

Even if a chicken's carrying campylobacter, if you handle it chicken properly and use appropriate techniques, you won't acquire it. But if there is a breakdown somewhere in the system and you do end up consuming some campylobacter and get sick, there's basically about a 20 percent chance that the campylobacter that you have just consumed is not going to be killed by Ciprofloxacin. That's a problem. This is in comparison, say, to the early 1990s, when probably only 1-3 percent of campylobacter were resistant to something like Ciprofloxacin.

Microorganisms tend to develop resistance to Ciprofloxacin fairly easily. We become concerned about our ability to use Ciprofloxacin as a means of treating campylobacter infections because of the rapidly increasing rates of resistance. [We are concerned that] because of the large amounts of antibiotics we're using, we are developing increasingly resistant microorganisms and we are reducing our ability as physicians to treat patients who come into us with infections. No longer can you assume that whatever the person is infected with you can treat it. Frequently we're beginning to encounter these microorganisms that in some cases are not susceptible to the first line or second line or even third line treatment. There are strains of salmonella which are resistant to a large number of antibiotics. And while they are still potentially treatable, most of our standard drugs will not work against some of these strains. Our concern is that the use of antibiotics in an agricultural setting is one of the things that's contributing to the emergence of these strains.

And, of course, Ciprofloxacin is used for a variety of other settings. It's the drug that is now one of the primary drugs for treatment of anthrax. ... These days Ciprofloxacin is on everybody's mind. It's a potentially very valuable drug, and to see development of resistance to Ciprofloxacin is always troubling.

How clear is the link between the resistance in animals and the resistance in humans?

In certain instances it's pretty clear, particularly if you're dealing with pathogens such as salmonella or campylobacter, which are not really passed from human to human. In most instances, they come through food. So when you see increasing problems with resistance in microorganisms that really originate primarily in food, it makes you look back at the food. In turn, it makes you look back at microorganisms that are present in the animals.

So, we're challenging our ability to use antibiotics by the overuse of antibiotics in our food supply.

Right. We're using a pretty good bit of antibiotic in our food supply for growth promotion, as well as for therapy. Esentially, what that's doing is developing generations of bacteria which now find it advantageous to carry around resistance genes. And those increasingly resistant bacteria are in turn moving into human populations. There's sort of this tendency to think, "Well, that's agriculture, this is humans," but we really are all together. It's a single ecosystem and we have to be concerned about what's happening in agriculture in terms of the development of resistance.

Can you explain the notion of "sub-therapeutic" antibiotics?

When antibiotics were first identified, the observation was made that if you fed animals low levels of antibiotics, lower levels than would be used to treat an infection, for some reason they grew a little bit better, put on a little bit more weight, and that little bit better growth can be the difference between profit and loss in a really tight, low-profit margin operation. And so, consequently, what has happened is that it has become almost standard practice in our factory farming agriculture here in the United States to use antibiotics as growth promoters.

The problem is that if you were to design a methodology for selecting out for antibiotic resistance, this would be the way you'd do it. In the laboratory, when we want to select out for resistance, what we tend to do is to treat bacteria with levels of antibiotics that are not enough to kill them, but enough to make them want to pick up or develop resistance genes. Consequently, you've got a setting in which you are actually encouraging the development of resistance. There's the feeling that to be able to make it economically, you have to use the antibiotics, to be able to get away with the tight crowding and all the other things that are used in agriculture, you need a little bit of antibiotic.

The tradeoff is that what you do is increase the risk that you're going to develop resistant microorganisms, which are going to develop and select out resistance genes, which in turn can reduce our ability to use antibiotics to treat infections in humans as well as in animals.

Do we know how much antibiotics are fed to the animals we eat?

Antibiotics used in animal feeds are not something that there are good records on. You can go to a feed store and buy a sack of feed with antibiotics without a prescription. The drug companies have not provided good data on how much antibiotic is being used. This is a major area of controversy between some of the environmental groups and some of the producer groups. There's actually a several-fold difference between what environment groups think may actually be being used and what industry groups say is being used. It's fascinating that in regard to something that should be simple there simply is no good data out there. There's no federal regulation that really allows us to know how much antibiotic is being used in agriculture. And the drug companies are not going out of their way to make that data readily available. So we really don't know how much antibiotic is being used in agriculture in this country. And that's kind of scary.

How good is the data out there on food-borne illness?

... I spent some time working with the CDC, working with this data back in the early 1980s, and it was very apparent that the quality of the data essentially bordered on being unusable, and that we really didn't have a good handle on how much disease was occurring. As we began to move forward to developing a new regulatory system, we felt that an absolutely critical component of this was to put in place some way of measuring outcome. Because what we were assuming was, if we could reduce the levels of contamination, we would have an impact on the occurrence of disease in human populations.

What we did was set up a system that that now lives under the name of FoodNet. ... The data we have today, while still not perfect, is much better than we had even five years ago. ...

Prior to 1995, all the health departments in the country were reporting cases of food-borne disease to the CDC. The problem was the reporting was spotty, it varied widely from state to state, or even from month to month. And in many instances, [it] was dependent whether or not there was somebody sitting in the office who had some spare time to chase down some food-borne disease cases. There really wasn't an adequate infrastructure or an adequate commitment to get good data.

It was very obvious that we didn't really have a good handle on what was happening at a national level. The alternate approach, rather than getting bad data from a lot of places is to essentially put all your money into getting good data from a much more limited number of places. That's the approach that's been taken with FoodNet. Which is to say we're going to pick what we call sentinel sites and put sufficient funds into collection of data in those sites. We're actually going to go out to the all the microbiology labs, make sure we don't miss any cultures, make sure that everything possible is being done to get the data and to really understand what's going on in those certain locations. And so that's what we have today. It's a good system.

Can you describe PulseNet?

PulseNet is an interesting supplement to FoodNet. FoodNet looks at the occurrence of disease in a limited number of sites very intensively. But one of the things that also was becoming apparent was that we didn't know that much about how specific bacteria might be moved around and what the relationship among different bacteria might be. In the past, we've always talked about sporadic cases. Those are cases that occur that may not be part of a food-borne disease outbreak. ... One of the things that's been happening is that we have started using molecular techniques to fingerprint bacteria, to try to see the relationships between this case that happens over here and this case over here. To do this, we've developed a national system which is what we call PulseNet. The whole thing is computerized on the Internet, and what that means is that for the laboratories that are participating in PulseNet, if you get salmonella isolate, you can actually put its fingerprint up on the Internet on the PulseNet system, and see if it matches anything that's coming in from anywhere else.

It's been very interesting, because suddenly what's happened is that you're starting to find that these isolated incidents actually are frequently parts of larger outbreaks, where there seem to be multiple people who may have been infected from some common source.

Can you describe the genesis of HACCP?

What we said was, "We're going to change the ground rules here, guys." Up until now, the inspector was the one that was in charge in the plant. The inspector was the one responsible, and the factory just did its thing, and they really weren't responsible for safety. There was the feeling that safety is the responsibility of the USDA inspector and that [the producer's] responsibility was limited to making a good product and trying to keep costs down. So we came back in and said, "That's not quite right." Safety needs to be a primary responsibility for the company. The company needs to really know what its problems are. It needs to know what hazards are associated with its product. It needs to figure out the best way for its plant to try to minimize those risks, and put in place what we call a Hazard Analysis and Critical Control Point [HACCP] system.

And so what we did was mandate that the slaughterhouses, the processing plants, had to put together a HACCP plan; they had to work through the science; they had to figure out what their hazards were; they had to write it down and figure out how they were going to try to decrease risks.

[HACCP shifts] the responsibility from what has been called a "command and control" type system -- where the government simply comes in and says, "You have to do it this way" -- to a system that says, "You're ultimately responsible as the plant owner for the product that you produce, and for the safety of that product. And you've got to put in place a system that is safety-oriented, that is designed to reduce the hazard of the product you're producing."

We said, "You're going to have to start doing some microbial testing and the government is going to come in periodically and do a random sample of your product, and we're going to see whether or not you are indeed maintaining an appropriate level of microbial contamination, or you are within an appropriate standard." And that was unheard of in the industry. You looked at the carcass. But the concept of actually culturing that carcass was something that was fairly new for much of the industry. That was information they didn't really want to know.

So what we did was actually set standards. Now, how do you set a standard? What do you use? There are an awful lot of questions that came up, and there were an awful lot of days that were spent sitting around the table bouncing ideas around, trying to work through and develop an appropriate system.

Ultimately, what we put in place was a system that's based on salmonella testing on the part of the government. So, essentially, the government has the right to come into a slaughterhouse or a processing plant and test product to see what the level of salmonella contamination is. And if that level is too high, then the government can tell the plant they need to reassess their current HACCP system and, ultimately, if that level of salmonella stays too high, the government has the ability to shut down the plant. ...

[Editor's Note: Since this interview with Morris was conducted, a federal appeals court decision held that the USDA did not have the authority to shut down a meat-processing plant based on salmonella testing alone.]

Can you explain the impact of the Jack in the Box E. coli outbreak on food safety?

Jack in the Box is an example of where you had a company that had a major problem. That company's response to the problem was to put in place one of the best food-safety systems in the country. They have phenomenal quality control, safety standards, HACCP, and microbiologically based systems. If you really want to know that the meat you're getting is the best possible with minimal risk, go to Jack in the Box. They do a great job.

Isn't there some irony in that the meat at fast-food restaurants is safer than what the U.S. government can guarantee it to be?

I think there is a great deal of irony in this. And I think there are several take-home messages. One is that if industry truly believes and sees the advantage, they can produce a high quality, very safe product. A highly dedicated company can work wonders. It has to see that safety is something that is important, and, to be very crass, is something that's profitable.

I'm curious, what was the industry's reaction to your team at USDA?

The industry was not overly happy to be perfectly honest. Mike Taylor [administrator of the USDA's Food Safety and Inspection Service (FSIS) from 1994 to 1996] came in, and soon after his arrival, he aroused a major firestorm by declaring that E. coli O157:H7 was an adulterant in ground beef. [Previously] the producers really didn't have any issues to worry about in terms of legal liability: "So I've got E. coli 0157:H7 in my meat? It's a natural part of the meat." What Mike said was, "No, it's not a natural part of the meat. It is an adulterant." Until that point, there had been the legally accepted concept that bacteria, including pathogenic bacteria, was a normal part of meat and poultry. And suddenly, that turned the industry on its ear. And it was really amazing to watch the response, and the sudden realization on the part of industry that these guys are for real; they're really going to do something.

Did you feel the heat from industry?

There was definitely heat. They filed suit immediately. There was very strong protest on the part of industry. There were lots of public meetings. There were lots of protests. There were presidents of major meat companies flying in in private planes to have closed door meetings with Mike Taylor. They said, "Hey, you can't do this." But Mike stood his ground, and that was the first, necessary step toward moving toward implementation of a risk-based system, but also a system, as I said, that puts the responsibility on the plant. In this case, the government won and the industry lost. And we were allowed to continue to call E. coli O157:H7 in ground beef an adulterant. From a legal standpoint, that was a tremendous step forward because that meant, from a regulatory standpoint, we could condemn a batch of meat that had E. coli 0157:H7 in it. We could say, "There's something wrong with this meat." And it was again a warning to the industry that they were going to have to assume responsibility.

home + industrial meat + interviews + the politics of meat + is your meat safe? + the inspection system
inside the slaughterhouse + producer chat + introduction + discussion + video
tapes & transcripts + press reaction + credits + privacy policy
FRONTLINE + wgbh + pbsi

web site copyright WGBH educational foundation

SUPPORT PROVIDED BY