USDA Announces Further Analysis Of BSE Test Results; Sample To Go To Weybridge
This evening at 9:00 p.m. eastern time, USDA held a media briefing on BSE. Agriculture Secretary Mike Johanns reminded participants that during the course of the enhanced BSE surveillance program to date, three BSE rapid tests resulted in an inconclusive result. Each of these tests was followed by a confirmatory immunohistochemistry (IHC) test; each IHC was negative. Recently, during an Office of the Inspector General (OIG) audit of the BSE surveillance program, the OIG determined that each of these samples should also be tested using another commonly used test, called Western Blot. While two of these initial inconclusives again confirmed negative using the Western Blot test, one of the retested samples was a reactor, or positive, when the Western Blot was performed.
Since this single sample has conflicting results, the sample will be forwarded to the World Reference Laboratory in Weybridge, England for final confirmation. USDA expects to have protocols for that confirmation developed early next week, but did not comment on when it expects to receive final results from Weybridge.
The sample in question was from an inconclusive announced in November, 2004. The animal did not enter the food or feed chain. USDA has said the animal in question was an older animal and a beef breed. The animal was non-ambulatory when presented for rendering and was condemned and incinerated.
NCBA Statement Regarding Today's USDA Announcement
Jim McAdams, President, National Cattlemen's Beef Association
"The U.S. Department of Agriculture (USDA) announced this evening they are sending a brain sample to the BSE World Reference Laboratory in Weybridge, England, from one of the three cows that tested inconclusive and was later confirmed negative in 2004. A separate test was requested by the USDA's Office of Inspector General on all three samples, and one of the tests returned positive.
"This aged animal never entered the human food or animal feed supply.
"Multiple tests can identify BSE. One commonly used method is the internationally recognized immunohistochemistry (IHC) test. Another test commonly used is the Western Blot test. These two types of tests have returned conflicting results on this sample.
"U.S. beef consumers should know that our beef supply is safe from BSE because we prohibit from the food supply any material that could carry the BSE agent (specified risk materials, or SRMs). USDA also bans from the food supply any cattle that appear to be high-risk, including this animal.
"The National Cattlemen's Beef Association (NCBA) supports getting a clear and definitive answer on this sample as quickly as possible and requests USDA Secretary Johanns take whatever steps are necessary to do so.
"NCBA has supported the aggressive BSE surveillance program and will continue to support a thorough evaluation. To date, 375,360 samples have been tested as part of this aggressive surveillance program that started on June 1, 2004, only three tested inconclusive. Two of these samples have been confirmed negative by both tests.
"NCBA expects USDA to act with speed and accuracy in reaching final resolution to this situation."
Statement By Dr. John Clifford Regarding Further Analysis Of BSE Inconclusive Test Results
"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. Three of these animals tested inconclusive and were subsequently subjected to immunohistochemistry, or IHC, testing. The IHC is an internationally recognized confirmatory test for BSE. All three inconclusive samples tested negative using IHC.
"Earlier this week, USDA's Office of the Inspector General (OIG), which has been partnering with the Animal and Plant Health Inspection Service, the Food Safety and Inspection Service, and the Agricultural Research Service by impartially reviewing BSE-related activities and making recommendations for improvement, recommended that all three of these samples be subjected to a second internationally recognized confirmatory test, the OIE-recognized SAF immunoblot test, often referred to as the Western blot test. We received final results a short time ago. Of the three samples, two were negative, but the third came back reactive.
"Because of the conflicting results on the IHC and Western blot tests, 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.
"Regardless of the outcome, it is critical to note that USDA has in place a sound system of interlocking safeguards to protect human and animal health from BSE-including, most significantly, a ban on specified risk materials from the human food supply. In the case of this animal, it was a non-ambulatory (downer) animal and as such was banned from the food supply. It was processed at a facility that handles only animals unsuitable for human consumption, and the carcass was incinerated.
"USDA's enhanced surveillance program is designed to provide information about the level of prevalence of BSE in the United States. Since the inception of this program, we have fully anticipated the possibility that additional cases of BSE would be found. And, in fact, we are extremely gratified that to date, more than 375,000 animals have been tested for the disease and, with the exception of the conflicting results we have received on this one animal, all have ultimately proven to be negative for the disease.
"USDA is committed to ensuring that our BSE program is the best that it can be, keeping pace with science and international guidelines, and to considering recommendations made by OIG and others in this regard. We are committed to ensuring that we have the right protocols in place-ones that are solidly grounded in science and consistently followed. 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."