This report provides a chronology of selected events leading up to and following thediscoveries of bovine spongiform encephalopathy (BSE, or "mad cow disease") in North America. As of this writing, 10 native cases have been confirmed on this continent, seven in Canada and threein the United States. (1) BSE is a degenerative disease that is fatal to cattle, affecting their nervous system, and it has beenlinked to a rare but fatal human form of the disease which has occurred primarily in the UnitedKingdom, where most BSE cases also have been reported. The following chronology is not intended to be comprehensive. It is intended to be a timelinefor selected regulatory, legal, and congressional developments that are frequently referenced in theongoing policy debate. It does not contain entries for the introduction of the many BSE-related billsintroduced into this or previous Congresses, except for those in recent years where committee orfloor action has occurred or where markedly widespread attention has been focused. Nor does itcover a number of policy developments that are not directly BSE-related, but that nonetheless havearisen within the context of BSE debate, such as a universal animal identification (ID) program andcountry of original labeling (COOL) for meats and other commodities. Other CRS reports may provide more background and context for this policy debate. Theseinclude: CRS Report RS22345 , BSE ("Mad Cow Disease"): A Brief Overview , by[author name scrubbed]; CRS Report RL32414 , The Private Testing of Mad Cow Disease: Legal Issues ,by Stephen R. ViÃ±a; CRS Report RS21709 , Mad Cow Disease and U.S. Beef Trade , by Charles E.Hanrahan and [author name scrubbed]; and CRS Report RL32199 , Bovine Spongiform Encephalopathy (BSE or "Mad CowDisease"): Current and Proposed Safeguards , by [author name scrubbed] and Sarah A.Lister. Unless noted, the sources for the entries in this chronology are the above reports, as well asvarious U.S. Department of Agriculture (USDA) and Food and Drug Administration (FDA) pressreleases, fact sheets, and other publicly available materials, reports of hearings before the House andSenate Agriculture Committees, and for some entries, articles that appeared in leading food andagriculture trade periodicals including Food Chemical News , Feedstuffs , and Cattle Buyers Weekly . For an explanation of these and related BSE terms in this report, see the reports listed on theprevious page, and also CRS Report 97-905, Agriculture: A Glossary of Terms, Programs, andLaws, 2005 Edition , by [author name scrubbed], coordinator. When BSE was first identified in 1986 in a British laboratory, relatively little was knownabout its character, its cause, or how to contain it. The United Kingdom (UK) has so far been thehardest-hit region, where reported cases affecting cattle continued to climb through the late 1980sand early 1990s to a peak of more than 37,000 in 1992. Cases have been declining each year sincethen. Several other countries, primarily in other parts of Europe, also reported hundreds of additionalcases, according to the world animal health organization (OIE, its French acronym). As the UK and other countries were coping with BSE, the U.S. and Canadian governmentswere establishing panels to study the disease and instituting a series of safeguards aimed at keepingit out of North America or stopping any spread if it should occur here. Prior to 2003, the only knowncase of BSE in North America was in Canada, where a non-native case was discovered in late 1993. This animal is believed to have been born in and imported from Great Britain in 1987. The first native-born case of BSE in North America was confirmed in a cow in Alberta,Canada, in May 2003. The United States almost immediately halted the importation of virtually allruminants and ruminant products, including live cattle and beef, from Canada. (An interim final rulewas published in the May 29 Federal Register , retroactive to May 20.) In August, the U.S. Secretaryof Agriculture announced that the U.S. border would reopen to boneless beef from cattle under 30months old and other items considered to be of low risk for BSE. Rather than issuing a proposedor interim rule, USDA claimed authority to proceed under a standing veterinary import permittingprocess. In November, USDA proposed for comment a more extensive rule change that essentiallywould formalize and expand imports from Canada, to include among other things live cattle under30 months old. Shortly thereafter, testing of a cow in Mabton, Washington, indicated the presenceof the BSE agent. Confirmatory testing affirmed BSE, and the U.S. Secretary of Agriculture reportedthe findings on December 23. This became the first reported U.S. case, although investigatorsquickly determined that the animal was not native but rather was born in and imported from Canada. USDA, cattlemen, and meat industry officials scrambled to reassure U.S. and foreignconsumers that U.S. beef was safe and, as the year closed, the Secretary of Agriculture announcedthat she would take a number of major steps to strengthen existing U.S. BSE safeguards. Althoughdomestic demand remained firm, most foreign countries closed their borders to U.S. beef and liveruminants including cattle. USDA moved to implement the new measures it had announced at the close of 2003, whileat the same time it worked to restore full cross-border trade with Canada and Mexico. In the springof 2004, however, a cattlemen's group successfully sued USDA to halt any further expansion ofCanadian beef imports in a federal court. USDA then agreed to limit such beef imports to the typesit began permitting in August 2003, until it promulgated a rule finalizing its November 4, 2003,proposal. The enhanced BSE surveillance program began in earnest in June 2004; initial screening testsreported three possibly positive cases during the year (which USDA termed "inconclusives") thatlater were deemed to be negative for BSE. Nonetheless, cattle and beef markets reacted nervouslyto the reports; USDA was challenged sharply on the adequacy of their design and conduct of thetesting program and how results were being reported prior to final confirmation. At FDA, whereofficials had promised early in 2004 to revise their animal feed rules to tighten controls over possibleBSE contamination, deliberations over the rules continued through the end of the year. Some countries, notably Canada and Mexico, were again accepting some U.S. beef in 2004,as were several smaller country markets. But Japan and South Korea, the other top two destinationsfor U.S. beef, remained closed, despite what appeared to be a hopeful joint announcement in Octoberby the United States and Japan of a "framework" agreement for restarting U.S. exports there. In early 2005, as USDA was unveiling its new rule for permitting Canadian imports, Canadawas announcing two additional discoveries of BSE. This brought to four Canada's reportednative-born cases (including the one found in the United States). U.S. officials expressed confidencein Canadian BSE safeguards but sent a team to confirm that feed controls there were effective. R-CALF USA again sued USDA to halt Canadian beef and live cattle imports, winning atemporary injunction in early March against implementation of USDA's January 4, 2005, final rule. However, an appeals court ruled in July to stay (reverse) the lower court's ban. Younger Canadiancattle soon began crossing the border for the first time in more than two years. As Japan was engaged in what many U.S. critics regarded as a needlessly slow regulatoryprocess toward lifting its ban on U.S. beef imports, USDA reported, in June 2005, the second U.S.case of BSE, but the first to be confirmed in a native-born cow. The Texas animal initially had beensampled for BSE in November 2004. Screening tests at that time came back inconclusive (i.e.,possibly positive) for the disease, but follow-up testing failed to confirm it, USDA said inannouncing a negative result. However, at OIG's urging, department scientists re-tested samples inJune 2005, and the results were positive for BSE. In Japan, the regulatory process along withcontinued consumer resistance there delayed the border opening until December, when some U.S.beef imports began to be accepted again. In Congress, mounting frustration led to the introduction of several measures aimed atcoercing Japan into moving more quickly to reopen its border. One such measure passed the Senatein September as an amendment to the pending USDA appropriation, but it was removed inconference. (The Senate had voted in early March to block the USDA rule permitting Canadiancattle to enter, but necessary House action did not occur.) Efforts to fully restore beef and cattle trade encountered several setbacks in 2006. First,Japan in January again halted all U.S. beef imports after finding some vertebral bones in a shipmentof veal. U.S. and industry officials were forced to redouble their efforts, and agree to additionalconcessions, to regain market access, which Japan finally granted in late July. U.S. beef exportswere expected to arrive there starting in August. However, an agreement on the terms for shippingbeef and cattle to Korea continued to elude negotiators during the first half of 2006. These effortswere exacerbated somewhat by the confirmation in March 2006 of a second U.S.-born cow withBSE. U.S. beef trade with Canada continued, despite that country's finding of four additionalBSE-positive cattle. U.S. and Canadian officials stated that the new findings were not unexpectedand still within the limits permitted under the OIE guidelines for trading with a country with someBSE. However, several of the animals had been born after Canada's 1997 ban on feedingmammalian protein to ruminants, raising concerns about the effectiveness and enforcement of theban. Critics urged USDA to reconsider its proposed rules (now being reviewed prior to formalpublication in the Federal Register ) to permit the importation of older Canadian cattle and/or otherruminant products. Meanwhile, USDA officials announced in July that the Department would soon scale backits massive BSE testing program, reverting to a lower level of ongoing surveillance, afterdetermining that the potential level of the disease in the U.S. cattle herd is very low. At the time of this report, the Administration and many Members of Congress werecontinuing to focus on efforts to reopen more major foreign markets to U.S. beef, most notablyKorea. They also were awaiting the restart of beef exports to Japan, which officials in that countryhad promised would begin shortly after a successful round of U.S. plant inspections in July 2006. At hearings and other venues, U.S. policymakers and industry officials had been expressingfrustration with the pace of these market-opening efforts. Bills (such as S. 3364 , S. 3538 , and H.R. 5675 ) demanding trade sanctions against Japan havebeen introduced but likely will not be acted upon if the market does reopen as anticipated. (Asnoted, the pending Senate version of the FY2007 USDA appropriation, H.R. 5384 ,includes a committee-approved, nonbinding amendment recommending such sanctions.) After more than two years of intensive surveillance, with more than 764,000 tests ofhigher-risk cattle, only two U.S.-born BSE cases have been confirmed, according to USDA. Yetsome remain concerned about the disease and its potential threat to public health as well as trade,particularly in the wake of several additional findings of BSE in cattle. The age of several of theCanadian cattle -- that is, they were born after the implementation in 1997 of stronger cattle feedrules to protect against BSE -- has been cited as a worrisome development by some critics of NorthAmerican BSE safeguards. However, Canadian, USDA, and industry officials continue to argue that the overall NorthAmerican risk profile is unchanged. They have long warned that several additional BSE-positivecattle might be found, but should be no cause for alarm. These officials have repeatedly attemptedto reassure consumers and foreign buyers that U.S. cattle and beef are safe and pose no risk to animalhealth or to human food safety (although research into the numerous unknown aspects of the diseaseand of the TSE family of diseases, and consideration of additional regulatory safeguards, continues). Few observers had expected the trade and economic issues to be resolved quickly. Nonetheless, frustrations continue to mount over the length of time it has taken to regain entry intothe Japanese and Korean markets. Even after U.S. beef becomes eligible for Japanese importation,the industry faces the difficult task of both meeting restrictive Japanese requirements, and thenregaining the market share there that other countries, notably Australia, have since captured. Efforts to restore beef and cattle trade between the United States and Canada have been morefruitful, although some U.S. cattlemen continue to express concerns about the potential impacts onU.S. cattle health. Meanwhile, Congress can be expected to play a continued role, holding oversighthearings, providing funding for BSE-related activities, and possibly considering legislative optionsto address one or more of the problems at hand.

Summary: This report provides a chronology of selected events leading up to and following thediscoveries of bovine spongiform encephalopathy (BSE, or "mad cow disease") in North America. These are primarily regulatory, legal, and congressional developments that are frequently referencedin the ongoing policy debate. The chronology generally does not contain entries for the introductionof the many BSE-related bills introduced into this or previous Congresses, except for those in recentyears where committee or floor action has occurred. This report, which will be updated if significantdevelopments ensue, is intended to be used alongside other CRS reports that provide morebackground and context for the BSE policy debate, and that cover many specific legislativeproposals. The chronology begins in 1986, when BSE was first identified by a British laboratory. Asthe United Kingdom and others attempted to understand and contain BSE, the U.S. and Canadiangovernments were establishing panels to study the disease and began instituting a series ofsafeguards aimed at keeping it out of North America or stopping any spread if it should occur here. The chronology proceeds into May 2003, when Canada reported the first native case in NorthAmerica; December 2003, when the United States reported finding a case in a U.S. herd; and mostof 2004, when both countries worked to reassure consumers of the safety of North American cattleand beef and to reopen foreign markets blocking these exports. U.S. and Canadian officials since2003 also have been strengthening various regulatory safeguards aimed at protecting the cattle herdand the food supply from BSE. The chronology continues with major events of 2004, 2005, and the first half of 2006, whichhave revolved around efforts to re-establish more open cattle and beef trade within North America,even while a handful of new cases of BSE have emerged here, and the steps being taken to regainthe Japanese and Korean markets, which were until December 2003 two of the four leading foreignbuyers of U.S. beef. Both were closed as of mid-2006 (although Japan appeared on the verge ofreopening as of this writing). Congress can be expected to continue to play a role, holding oversighthearings, providing funding for BSE-related activities, and possibly considering legislative optionsto address one or more of the outstanding issues.