Mad Cow Disease Alert from Canada

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• JIM LEHRER:

  Now, the mad cow disease alert from Canada, and to Ray Suarez.

• RAY SUAREZ:

  For the first time in ten years, a case of mad cow disease was found in North America in a single cow in Alberta, Canada. The country's agricultural minister made the announcement yesterday. He said the eight-year was destroyed in January after showing signs of the disease. That announcement prompted the United States to immediately ban all beef imports from Canada. We get the latest now on the situation from Dr. Lester Crawford, the deputy commissioner of the Food and Drug Administration. Dr. Crawford, help us understand why one cow found to be affected in a Canadian herd of 3.6 million is a serious thing.

• DR. LESTER CRAWFORD:

  Well, we don't know the extent of the infection. This one cow has been discovered and she definitely has the disease. It was confirmed in the United Kingdom. What is going on now is the Canadian government is doing an excellent job of tracing down where she came from, what she had eaten and whether or not herd mates not only this herd but the previous herd she was in have the disease. Right now we're in a wait and see proposition. Ten years ago as you mentioned we only had the one case so the bans we put in on the border and other countries followed suit. It only lasted a very short time, but we don't have enough information to know how long this is going to be.

• RAY SUAREZ:

  Has the science moved forward far enough so that you'll ever be able to really now hoe that one cow contracted this?

• DR. LESTER CRAWFORD:

  The science has moved forward a great zeal since 1993. When the U.S. put in their program we had almost no way to defendant for the disease under any circumstances so everything was by gross pathology and was done indirectly. Now we can do the testing and we will probably eventually know what caused this particular animal to come down with the disease. It's a mystery at this point though because we don't have feeding records on the cow.

• RAY SUAREZ:

  Do we know yet for sure whether there's a risk for human beings whether in the ingestion of the affected food you get the manifestation, the human form of disease?

• DR. LESTER CRAWFORD:

  There's a human form that experts in the field believe is significantly different from the disease that occurs normally in human beings. There are several forms of disease that occurs in humans. But this one is so different it's called new variant CJD, or Creutzfeldt-Jakob disease. There's little disagreement in the scientific and medical community that consumption of the infected material from a beef carcass will cause the disease in human beings. There have been over 100 deaths from this particular form of this disease in the United Kingdom and it is felt almost beyond a shadow of a doubt that it comes from consumption of the meat.

• RAY SUAREZ:

  With an enormous beef industry in the United States and an international market in cows and beef products how do you keep the American consumer safe?

• DR. LESTER CRAWFORD:

  What we decided to do in 89, we were the first country to put in what was called at the time a draconian program – this was when I was in the Department of Agriculture and had a little bit to do with it. We decided based op the science we had it could possibly be a risk to human being and we believed it would decimate the United States beef industry and be a terrible blow in our economy so we essentially put up a wall around the United States. We banned all things British. We were about to become some what self-satisfied until we had that one case in '93 in Canada and then we tested our system and you know we're very, very careful about this. The organization in the Department of Agriculture that protects us from live animal diseases like foot and mouth disease and so far is just an exceptional cadre of public servants and they have been so good at foot and mouth disease we haven't had it since 1929. We're the only western country that hasn't had BSE or mat cow disease.

• RAY SUAREZ:

  The American consumer really doesn't have to worry there's no self-protection measures or anything like that that need to be take money is the.

• DR. LESTER CRAWFORD:

  We worry a lot for them. What the population of this country does need to be concerned about if they travel to BSE countries they should heed advisories. They should heed advisories; these are very simple kinds of things. They also would want to know that we're taking the Canadian incident seriously. We're working with the Canadian government. We get briefings at FDA daily from them. I just got off the phone with them a short time ago. We believe they are doing a great job in dealing with the problem but this government is going to have to be satisfied before we reopen the borders.

• RAY SUAREZ:

  We know that cows don't give it to each other. Do we know how they get it?

• DR. LESTER CRAWFORD:

  There's some evidence. In 1989 we were talking about this disease, someone said we know about as much about this disease as we knew about smallpox at the time of Christ. We now know a little bit more than that. And we're learning more all the time but we still don't know exactly how the animal gets the disease. We know that it has to be condition assumed. They have to eat the infectious material but exactly how it gets from the stomach until the case of cattle – four stomachs — all the way to the brain is not clearly worked out — may not be worked out for a long, long time. We know what happens in the brain and we have characterized the disease, it doesn't appear to be at this point amenable to vaccination or to therapy. It's always fatal, and this particular cow that has the disease in Canada, we don't know the origin of her so it's possible that she could have come from another country into Canada. That's yet to be determined. But if she was Canadian born and bred and has been there all her life how she got infectious material is going to be a big mystery. There's importation of cattle feed in virtually almost every country and the fact is that this is eight and a half years ago so — old so at the time of her birth they didn't have the restrictions in Canada and neither did we, which would have protected her from this. It's possible that it could be an old infection. The incubation period in cattle is normally about four and a half years but it can go up to seven years in extreme cases. So maybe it was an exposure a long, long time ago; we just don't know yet.

• RAY SUAREZ:

  Well, the tracing system that's been put in place in response to mad cow disease — I need to know more about it. Is it as reliable as the vin number on an automobile?

• DR. LESTER CRAWFORD:

  Yeah, the Canadians have a system which we're fully aware of and we believe that works. What it does is they register the cattle with a unique number. They place a tag or other identifying device in the animal's ear or somewhere else in the carcass and they are able to find out where it has been all of its life by consulting the registry. That's what they are doing now. Once they find a spot where she was three years ago — this herd she is in now was only formed three ears ago. They essentially have to go back to the herd and confirm that in fact she was there once they find it and they have to go all the way back to the time she was born. I think this system works well.

• RAY SUAREZ:

  Dr. Lester Crawford, thanks for being with us.

• DR. LESTER CRAWFORD:

  Thank you.