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(A newsletter, not a copyrighted article) BSE, BOVINE – USA: SUSPECTED (02): TESTS ***************************************** A ProMED-mail post http://www.promedmail.orgProMED-mail, a program of the International Society for Infectious Diseases http://www.isid.orDate: Sat, 11 Jun 2005 From: "Mary Marshall" <tropical.forestry@btinternet.com> Source: Web Cast Audio: U.S. Agriculture Officials To Provide Update On BSE Surveillance Testing - Requires Windows Media Player < http://easylink.ibroadcastsmedia.tv/ripariane/bse061005.wma>Transcript of Tele-News Conference with Agriculture Secretary Mike Johanns and Dr. John Clifford, Chief Veterinary Officer, Animal Plant Health Inspection Service Regarding Further Analysis of BSE Inconclusive Test Results Washington, D.C. < http://www.usda.gov/wps/portal/!ut/p/_s.7_0_A/7_0_1OB?contentidonly=true&contentid=2005/06/0207.xml> Release No. 0207.05 Contact: USDA Press Office (202)720-4623 10 June 2005
MR. ED LOYD: "Good evening, everyone, and thank you for joining us late on a Friday evening. I certainly appreciate your getting on with us on such short notice for an update of our BSE surveillance. Just so you know, our format tonight, Agriculture Secretary Mike Johanns is going to make a brief introductory statement, followed by Dr. John Clifford, the chief veterinary officer of the APHIS, the Animal Plant Health Inspection Service, who will go into some more technical background.
... DR. CLIFFORD: "Thank you, Mr. Secretary. And thanks everyone for being on the phone tonight.
"Since the USDA enhanced surveillance program for BSE began in June 2004 more than 375 000 animals from the targeted cattle population have been tested for BSE using a rapid test. 3 of these animals tested inconclusive and were subsequently subjected to the immunohistochemistry (IHC) testing. The IHC is an internationally recognized confirmatory test for BSE. All 3 inconclusive samples tested negative using the IHC test.
"As the Secretary said earlier this week, USDA's Office of Inspector General which has been partnering with APHIS, FSIS and ARS, the Agriculture Research Service, by impartially reviewing BSE-related activities and making recommendations for improvement, recommended that all 3 of these samples be subjected to a 2nd internationally recognized confirmatory test, the Western Blot.
"We received final results a short time ago... Of the 3 samples 2 were negative, but the 3rd came back reactive on that test.
"Because of the conflicting results on the IHC and Western Blot test, a sample from this animal will be sent to the OIE recognized reference laboratory for BSE in Weybridge, England. USDA will also be conducting further testing which will take several days to complete.
... "After we receive additional test results on this animal, we will determine what further steps need to be taken and what changes if any are warranted in our surveillance program."
MR. LOYD: "With that, Operator, we would open this up to some questions."
... REPORTER: "Yes, good evening. This is Peter Shinn from the National Association of Farm Broadcasters.
"Mr. Secretary, I don't mean to ask a difficult question, but it just immediately comes to mind. What exactly happened in terms of how could you have gotten it not right the first time? And what's the difference between the IHC and the Western Blot? "
SEC. JOHANNS: "Yeah. I'll ask Dr. Clifford to get in. It's not really a question of not getting it right. Both tests are accepted by the OIE. Both tests are accepted under the standard. So it's not a question of getting it right. All of the protocols were followed. We had the positive and the rapid response test, the IHC test was applied according to the protocols, and that is the test that has been used in the United States.
"And so it's not a situation where you've got one test that isn't accepted and one that is. They both are accepted. There are differences in the tests, and I'll let Dr. Clifford explain that. And maybe, Dr. Clifford, you can even explain just what this test showed and how you went about getting through the testing process."
DR. CLIFFORD: "Yes, we're confident in the results of actually both of these tests. The IHC was negative for this sample. Actually the Western Blot test, if you go back to the December <2004> cow that was found from Canada, the Western Blot that was run on that particular sample we used one milligram of tissue to run that test and it was found to be a very strong positive.
"In order to find a positive in this particular case with this Western Blot, they had to enhance or enrich it, which basically means you're concentrating the abnormal protein. So they had to use 20 times the amount. You would have to use about 20 times the amount of tissue for this to determine to be a positive or reactive on the Western Blot versus the one that was discovered in December <2004> in the state of Washington.
"In addition, there are definite differences between these 2 tests. The IHC is internationally recognized, and why we chose that for our enhanced surveillance program is because that particular test does 2 things. It allows you to visualize the anatomic location where the lesions are most likely to be found which is the obex . At the same time it uses a staining technique on the prions, on abnormal prions in the tissue in that location....
"In the Western Blot case, it's actually a homogenate of a sample of brain tissue that is centrifuged and they concentrate the prion protein and then they use a protease to destroy the normal protein, leaving the abnormal protein present. And then basically that is run through a gel-type separation using specific antibodies that will give you bands. And they look at those bands and the molecular weight of those bands to determine the outcome of that test.
"So this test would actually be referred to as a weak positive test in this case for the Western Blot, and as a result of that and the unusualness of this case it's going to require additional testing before we can confirm one way or another whether this is truly BSE or not.
"What we mean by "weak positive," is going back to the original case. It required and enrichment of these and a greater amount of normal tissue in order to enhance this outcome. So in order to find the abnormal protein present you had to use more material and concentrate it."
OPERATOR: "The next question will come from Joe Pelka (sp). Your line is open.
REPORTER: "Hi. Good evening, gentlemen. I actually have three questions. I think I can state them succinctly. First of all, why did the IG ask for a retest in this case? What do you expect they'll do differently at Weybridge that they do from Ames, Iowa, in the IHC testing? And which cow of the 3 r which animal of the 3 that had the earlier positives are we looking at tonight?
SEC. JOHANNS: "I'll answer the first one just as best as I can, and then Doctor, I'll just queue you up that I'll ask you to answer the final 2.
"The IG has been looking at the surveillance. As you know, we've tested now 375,000 animals, and Secretary Veneman wanted to be sure that we were touching the right places-- regions of the country and etcetera to make sure that when that surveillance was done we were satisfied that we got a good surveillance of the herd.
"Again, keep in mind that was a surveillance effort; it was never portrayed to be a food safety approach.
"In that effort I believe that the IG decided just to make sure that all the bases were touched that this additional testing should be done. So go ahead, Doctor."
DR. CLIFFORD: " The reason we're sending this to Weybridge is because we feel this is an unusual case, and we'd like to have the assistance of an internationally recognized laboratory for BSE.
"The inconclusive that we're referring to here is the one that we gave notification of in November of 2004. I think it was actually 15 Nov 2004. With regards to the OIG's recommendation, I think that recommendation was based upon a strong reaction on the biorad test and the negative IHC, and in order for us to try to resolve those discrepancies that have been raised relative to that."
REPORTER: "The November case, was that the Texas cow? If it was -"
SEC. JOHANNS: "You know, Elizabeth, I don't believe the USDA ever talked about location."
REPORTER: "I presume when you start doing trace back though for this animal you will be then talking about the location?"
SEC. JOHANNS: "You know, I haven't even gotten that far down the road. I just wanted to get the information out there as quickly as we had it. So."
REPORTER: "And we appreciate that, especially those of us who don't publish until Monday.
"A further question, at the time of that test I talked to a lot of people internationally and actually spoke to the scientist who developed the immunohistochemistry test, and he said while his test was state of the art when it was first developed he now considers it as he put it more art than science. And so I'm wondering, is USDA considering switching to one of the newer tests, say the one that Prusinger's Lab has created, something that's got a low false positive but is perhaps a more sensitive test because Europe thinks we've kind of outgrown the immunohistochemistry test.
SEC. JOHANNS: "Yes. You talk about the curiosity of timing; it just so happened that today I was touring our Ames laboratory facility in Ames, Iowa. And that had been set up well before this was an issue, and I just wanted to see how they were doing there. And I talked to many of the scientists that are involved in our BSE research, and I talked about the tests. And I probed very extensively about both tests being accepted under OIE standards.
"I believe at the risk of talking for scientists that you'd get a pretty lively debate about what test is best, under what circumstances is it best.
"I do know this, that the IHC test is recognized by the OIE. It's an accepted test. It's a test that we have employed and we're not alone. Other parts of the world do.
"We would never make a decision about changing protocol in a knee-jerk sort of way. We would certainly want to debate that. We would want to get a lot of good scientific analysis. So it's not something that we would do just very, very quickly. It's something I'd want very, very cautious, careful consideration about because there are some who say, 'No the IHC is where you want to be.'
"So like I said, at the risk of talking for scientists I think you could get a pretty lively debate on your question.
DR. CLIFFORD: "I just would like to add one thing, Mr. Secretary, or a couple of things. Again, to reiterate, we do not, we have not confirmed a case of BSE in the U.S. at this time. We're going to do further analysis and study on this.
"I'd also like to state for the audience, there is such a thing in Europe that is called "atypical BSE" about which there's a lot of information and data that is still needed out there. And in those particular cases, you have in some cases; you had where IHC has been negative and a Western Blot been positive.
"In addition with regards to the epidemiology, we have already done some preliminary epidemiology back when the 1st inconclusive was announced, and we'll be ready to perform that as necessary."
OPERATOR: "The next question comes from Libby Quaid. Your line is open."
REPORTER: "Thank you. Could you go into a little bit more on what test you expect will now be performed and when you expect to know for sure whether this was a positive or a negative test?"
DR. CLIFFORD: "Actually what I'd like to do is to provide that information -- our scientists are working in the Agriculture Research Service and APHIS in our National Veterinary Services Lab, and they'll also be discussing this with the scientists at Weybridge, and they'll be developing a protocol early next week and procedures for further testing."
OPERATOR: "The next question comes from Ken Root. Your line is open."
REPORTER: "Yes. Mr. Secretary, was this a native-born U.S. cow?"
SEC. JOHANNS: "That dates back to before I got to the USDA. Doctor, do you know if that's been released?"
DR. CLIFFORD: "Actually, Mr. Secretary, it has not. What I can say though is that at this time we would have no information that it was an imported animal; also that the animal was an aged animal. It was getting up in age and was a beef breed. That's what we're willing to release at this time."
OPERATOR: "Next question comes from Dan Goldstein. Your line is open."
REPORTER: " Two questions, one for Dr. Clifford and one for the Secretary. Mr. Secretary, first of all, does this somewhat do you think may shake the confidence of the international community, one, in the ability of the Ames Laboratory and, 2, also the efficacy of the IHC test?
"And then also for Dr. Clifford, what does this mean in terms of the protocols? Will you now have to go back and perhaps test more animals with Western Blot tests?"
SEC. JOHANNS: "Let me address the question about the Ames Laboratory, and I'm sure the doctor will want to offer a thought also.
"One of the things we are very, very proud of is that Ames laboratory. They do great work there, and again I remind everybody that the IHC test is an internationally accepted test. And that comes from the OIE, and like I said even amongst scientists you would get debate about the test.
"But it is an internationally accepted test. It was done according to protocol. It was properly done and produced negative results as the doctor explained.
"In terms of the confidence of the international community, I believe they look to us as leaders. Not only are we aggressive when it comes to this disease; we quite honestly don't leave any stone unturned in terms of our efforts to make sure that we're proceeding along the right pathway.
"As the doctor pointed out, this is an aged animal. Our discussions with Japan have related to 20-month animals as you know. Our discussions with Korea have related to 30-month animals, and the rule relative to Canada or the Minimal Risk Rule in general I should say relates to animals under 30 months and meat product under 30 months.
"So I really don't believe this has any impact on our international trading partners. We'll be working with them to get information in their hands and make sure that they understand the situation. But again just because of what we're talking about here and the age of the animal, we've got a vast difference between what this is about and what we're working with them about.
DR. CLIFFORD: "I agree wholeheartedly. Interationally our National Veterinary Services Lab is recognized and well respected, and this doesn't put any dent in their armor. They have run the IHC flawlessly, and we're confident in every result that's resulted from that IHC.
"We're confident in the result of the IHC with this particular animal. As I'd indicated earlier, and actually the ARS scientists as well as our own because this had to be enriched this wouldn't have been found – this particular case would have missed the type testing we did exactly on the December cow in Canada. It was the IHC and the Western Blot both in those cases that were found to be positive.
"We have also discussed this particular issue with international scientists, and I think they have complete confidence in our program while they also recognize and would recommend that this one particular animal because of the unusualness of this case they feel that it should have been run also against the Western Blot."
OPERATOR: "The next question comes from Tom Stever (sp). Your line is open."
REPORTER: "How frequently has the Western Blot test been used? And also what makes you think that this will not affect the ongoing efforts to reopen the borders to U.S. beef in Japan and Korea?"
SEC. JOHANNS: "Again, the doctor points out that this is an aged beef animal. What we are working with in terms of Canada as you know is 30 months and under. What we are working with Japan, because of a concession made in the negotiations, is 20 months and under, and then Korea 30 months and under.
"And again in terms of our firewalls that are in place, removal of specified risk material, the extensive surveillance that we have done, our diligence in the process of testing, I really do believe that this should not have any impact on the discussions that we are having with those countries. If anything, it should illustrate to them the diligence by which we pursue the safety of our feed supply and the safety of our supply of food for human consumption.
"The other thing I do want to mention is, again I point out that our firewall has worked here. This animal did not enter the food supply or the feed supply. There are a number of inter-related firewalls that we have in place, and again we have a prime example tonight that they work and this animal did not enter the food or feed supply.
DR. CLIFFORD: " Actually both of these tests are used extensively internationally, and it will vary from country to country as to which test they choose or whether they use both tests in some cases. And in most cases countries would not use both though, except under certain circumstances or unusual circumstances."
REPORTER: "Hi, there. Beth Gorham from the Canadian Press Wire Service. Thanks for taking my question.
"Mr. Secretary, I understand that you think that this isn't going to affect talks with international partners, but given the timing of this and I'm not quite clear -- I know the protocols are being developed next week, but, A, is there an answer on how long this will take? And B, given the fact that the appeal is scheduled to go ahead on 13 Jul <2005> in Seattle, are you worried about the impact as far as the judicial proceedings are concerned?"
SEC. JOHANNS: "You know, I am really not. And let me explain to you why. I believe that you will have the entire cattle industry over the next few days and the folks involved in processing beef and serving beef to customers recognize and talk very publicly about what we've talked about tonight. And that is that the firewalls we have in place do work.
"We did not have an animal that entered the feed or food chain. All of the protocols were followed. The laboratory in Ames meticulously followed the step-by-step process, came up with a negative, and I just think you're going to have the industry say, hey, what we see is that the USDA firewalls are working, they're getting the job done for us.
"And again as you know, Canada really follows the same approach that we do. So I just don't anticipate an issue there, and again I don't anticipate a problem with our trading partners. They'll want to know what the issues are and what we have done, and we'll provide them with that information.
"One of the things about this call tonight is, we want to assure them and to assure the public that what we're doing here is transparent. I had these results just barely 10 minutes before we got on the line to visit with you. So I think that's very important.
... SEC. JOHANNS: "Doctor, if you might -- and I don't want to extend this longer than necessary, but it might be good for a quick refresher on the significance of the rule specifying 30 months and under and in Japan's case 20 months and under. Do you know what I'm driving at?
DR. CLIFFORD: "With regard to the SRM removal, yes. Basically the animals under 30 months of age, you know with regards to SRM removal we remove the tonsils and small intestines, and over 30 months of age animals we remove the spinal cord, the small intestines, as well as tonsils, eyeballs, the brain tissue, and the dorsal root ganglia. Those are the tissues that are removed in order to protect the human health in this country."
OPERATOR: "The next question comes from Tom Brand. Your line is open.
REPORTER: "Good evening. Mr. Secretary, as we've been on this call here this evening I was actually with a group of some cattle producers and have been relaying some information along to them... They're interested in why we upped the sample amount to such, the 20 times, in order to get that positive? ...
... DR. CLIFFORD: "When you talk about the enrichment of the sample that's something that is allowed with regards to that test and the protocol in order to determine if there's low levels of abnormal protein present. And that's a technique that has been probably used in more recent years and is something that is widely used."
SEC. JOHANNS: "Okay. Let me just wrap up with just a couple of quick comments, and then we'll call it good for the night and we'll let you get off the line.
"The first thing I want to mention again is that there is no risk to human health here. The animal did not get in the food or the feed chain. The firewalls that the USDA put in place some time ago once again have shown that they do work. I do not believe that the information that we have released should impact our discussions with Japan, Korea or Canada. Again, age of animal alone would indicate we're dealing with a much different circumstance.
"And with that, I do want to point out that as the doctor indicated even this 3rd test is not a confirmed case of BSE. Additional testing will occur. The other 2 animals did test negative on the additional testing.
-- ProMED-mail <promed@promedmail.org>
BSE, bovine - USA: susp. 20050611.1625 BSE, bovine - Canada (04): OIE 20050125.0272 2004 ---- BSE, bovine - USA: susp (03) 20041118.3096 2003 ---- BSE, bovine - Canada (Alberta): confirmed 20030520.1241] ......................................jw *##########################################################* ************************************************************ ProMED-mail makes every effort to verify the reports that are posted, but the accuracy and completeness of the information, and of any statements or opinions based thereon, are not guaranteed. The reader assumes all risks in using information posted or archived by ProMED-mail. ISID and its associated service providers shall not be held responsible for errors or omissions or held liable for any damages incurred as a result of use or reliance upon posted or archived material. ************************************************************ Visit ProMED-mail's web site at <http://www.promedmail.org>. Send all items for posting to: promed@promedmail.org (NOT to an individual moderator). If you do not give your full name and affiliation, it may not be posted. Send commands to subscribe/unsubscribe, get archives, help, etc. to: majordomo@promedmail.org. For assistance from a human being send mail to: owner-promed@promedmail.org. ############################################################ ############################################################
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