We haven’t heard much lately about BSE, CJD or other prion diseases categorized as transmissible spongiform encephalopathies (TSEs) and that generally is a good thing.
Bovine spongiform encephalopathy (BSE) and the related human disease Creutzfeldt-Jakob disease (CJD) have fallen out of the headlines because interventions, here and abroad, have worked, and the diseases have become extremely rare.
Last week, the FDA announced the termination of its Transmissible Spongiform Encephalopathies Advisory Committee and its removal from the Agency's list of standing advisory committees.
The TSE Advisory Committee was established on June 9, 1995 to review and evaluate available scientific data and make recommendations to the FDA Commissioner regarding regulations. According to the FDA, “the number of issues requiring Committee advice has declined, and the Committee has met very infrequently. Therefore, the effort and expense of maintaining this advisory committee is no longer justified. TSE issues in the future will be addressed by other FDA committees.
BSE emerged in the late 1980s and early 1990s, primarily in the United Kingdom. Scientists soon linked the deadly wasting disease to cattle’s consumption of feeds containing animal byproducts that carried the misfolded proteins, known as prions, which cause the condition.
Globally, BSE peaked in 1992 when over 35,000 cases were identified. By 2012, the global incidence was reduced to 13 cases.
Scientists also linked the human form of the disease, variant Creutzfeldt-Jakob disease (vCJD) to consumption of beef contaminated with the BSE prions. Cases of vCJD peaked in the year 2000, when 28 people contracted the fatal disease. In the United States, only four cases of vCJD have been confirmed, and all of those people likely contracted the disease while living or traveling overseas.
In the early 1990s, the USDA issued import restrictions on beef from the United Kingdom and other countries with BSA and initiated a domestic surveillance program. Also, the FDA and USDA worked with beef processors to remove specific risk materials (SRMs), primarily nervous-system tissue, from beef carcasses. In 1997, based on scientific evidence, the FDA issued its original BSE-related feed restrictions, removing mammalian proteins from cattle feeds. In 2008, the agency issued its enhanced feed regulations banning high-risk cattle tissues from all animal feeds.
Between 2004 and 2008, the U.S. surveillance program resulted in testing of 750,000 cattle. In 2008 the surveillance program was scaled back to test around 40,000 cattle per year.
The first case of BSE found in the United States was in 2003, in a cow that had been imported from Canada. Since then, there was one confirmed case in Texas in 2005, one in Alabama in 2006 and one in California in 2012. Each of those domestic cases was determined to be a rare, atypical form of BSE that occurs naturally. In May, 2015, the World Organization for Animal Health (OIE) recognized atypical BSE as naturally occurring and determined that cases should not affect a country’s risk status.
In May 2013 the OIE upgraded the United States to its “negligible risk” rating for BSE, and most of our export customers have removed BSE related barriers to trade in U.S. beef.
Globally, an occasional case of BSE continues to crop up. France confirmed a case in March of this year, Canada had a case in February 2015 and Brazil confirmed a case in May 2014.
In March 2016, the FDA issued its final rule on BSE, which finalized three previously-issued interim rules designed to further reduce the potential risk of the disease. The rule provides definitions for prohibited cattle materials and prohibits their use in human food, dietary supplements and cosmetics.
The FDA video credits efforts to remove BSE risk materials from feeds for the dramatic reduction in cases. The agency stresses though, that the industry remain vigilant and compliant with regulations and feed-manufacturing practices intended to prevent BSE.