Key facts
- APHIS states that WOAH rates the US as negligible risk for BSE, and that the US had seven BSE cases from 2003 to 2023: one classical case in 2003 in a cow imported from Canada and six atypical cases, the latest in 2023.
- APHIS describes atypical BSE as arising spontaneously at a low rate and not linked to feed, citing a 2015 WOAH decision, while classical BSE spreads through contaminated feed; it shares the feed and specified risk material controls with USDA FSIS and the FDA.
- The APHIS BSE surveillance programme targets cattle with signs of BSE and cattle aged 30 months or more that are non-ambulatory or cannot rise or walk unaided.
- In August 2018 NVSL confirmed atypical H-type BSE in a six year old Florida beef cow first flagged by the Colorado State University Veterinary Diagnostic Laboratory, a National Animal Health Laboratory Network lab; the animal never entered slaughter channels.
- An ARS scientist at the National Animal Disease Center and an NVSL colleague reported in 2008 an H-type BSE case in an Alabama cow carrying a new E211K prion gene variant, the bovine match to human E200K.
- Under 9 CFR 55.8, official CWD tests are histology and protease resistant prion protein methods (immunohistochemistry or western blot) run to NVSL protocols, plus other tests the APHIS Administrator approves on data for reproducibility, sensitivity and specificity; APHIS also approves the state, federal and university labs that run them.
- The national CWD Herd Certification Program for farmed cervids began in 2014; in FY 2020 it covered 28 states, 2,145 enrolled herds and 1,723 certified herds, and 22 new CWD positive farmed herds were found that year.
- A 2022 study co-authored by NVSL and APHIS Cervid Health Program staff said official US CWD surveillance rests on immunohistochemistry run at NVSL and that RT-QuIC was not yet approved for official farmed cervid surveillance.
- In September 2024 APHIS Wildlife Services awarded USD 5.5 million for wild cervid CWD work, including USD 248,315 to the Colorado State University Prion Research Center, USD 250,000 to the University of Minnesota, and university awards for RT-QuIC and CRISPR based CWD assays.
- A December 2024 student news report said MNPRO at the University of Minnesota received USD 483,497 from USDA APHIS for further CWD work.
- An APHIS Veterinary Services scientist in Fort Collins co-authored the 2024 validation of rectal mucosa RT-QuIC for preclinical CWD in white-tailed deer (284 deer).
Timeline
- 2003First US BSE case, a classical case in a cow imported from Canada.
- 2008NVSL and NADC authors publish the H-type BSE case carrying E211K.
- 2014National CWD Herd Certification Program for farmed cervids begins.
- 2018APHIS announces NVSL confirmation of atypical H-type BSE in a Florida cow, the sixth US case.
- 2022APHIS co-authored study notes RT-QuIC not yet approved for official farmed cervid CWD surveillance.
- 2023Seventh US BSE case, atypical; the latest listed by APHIS.
- 2024APHIS co-authored rectal mucosa RT-QuIC validation in deer published.
- 2024Wild cervid CWD spending plan of USD 5.5 million published.
- 2024MNPRO APHIS award of USD 483,497 reported.
Sources for this page
- USDA APHIS: Bovine Spongiform Encephalopathy (programme page, print version, node 3298)
- USDA APHIS news bulletin: USDA Announces Atypical Bovine Spongiform Encephalopathy Detection (29 August 2018)
- Richt JA, Hall SM. BSE case associated with prion protein gene mutation. PLoS Pathog 2008;4(9):e1000156
- 9 CFR 55.8: Official CWD tests and approval of laboratories to conduct official CWD tests (Cornell LII reproduction of the eCFR)
- USDA APHIS: Voluntary Chronic Wasting Disease Herd Certification Program Annual Update, FY 2020
- Tewari D and others. Detection of chronic wasting disease in feces and recto-anal mucosal associated lymphoid tissues with RT-QuIC in a naturally infected farmed white-tailed deer herd. Front Vet Sci 2022;9:959555
- USDA APHIS: Wild Cervid Chronic Wasting Disease Management and Response Activities 2024 Cooperative Agreements, 2024 Spending Plan (September 2024)
- Minnesota Daily: MNPRO receives nearly $500,000 to continue chronic wasting disease research (1 December 2024)
- Piel RB and others. Validation of an RT-QuIC assay protocol to detect chronic wasting disease using rectal mucosa of naturally infected, pre-clinical white-tailed deer. PLoS One 2024;19(6):e0303037, PMID 38870153 (Europe PMC record)