Bovine Spongiform Encephalopathy Cases Research Articles

The Microscopic Detection of Animal Proteins in Animal Feed Regarding Bovine Spongiform Encephalopathy

Abstract Due to the actuality of spongiform encephalopathies and their proven spreading by means of animal feed containing meat and bone meal, the description and measurement of osteocytic lacunae contributes to more easily distinguish bone fragments in meat and bone meal. Transmissible spongiform encephalopathies (TSEs) have attracted a lot of attention, especially after 1986, when the first case of BSE (bovine spongiform encephalopathy) was detected. Since the outbreak of spongiform encephalopathy (BSE), the use of animal protein including bone meal as an ingredient in animal feed has been controlled by several regulations including Regulation (EC) 999/2001, Regulation (EC) 1774/2002, and Regulation (EC) 1234/2003. The classical microscopic method is the only official method for detecting animal protein in animal feed in the European Union (Commission Regulation (EC) 152/2009). By applying the microscopic method to the animal feed samples, we performed detection in order to determine the presence of animal proteins that originate from mammals and fish. The microscopic analysis of all 421 samples, of which 115 were raw materials for the production of animal feed, 230 were concentrates for ruminant nutrition and 76 were concentrates for non-ruminant nutrition (32 concentrates for laying hens and 44 concentrates for pigs), did not provide positive results, that is, no remains of animal tissues of mammalian origin were found in any specimen. Whereas in 10 out of 32 (31.25%) concentrates intended for non-ruminant nutrition (laying hens), pieces of fish tissue were found. In these samples, we usually detected the presence of fish bones, gills and scales.

Analysis of German BSE Surveillance Data: Estimation of the Prevalence of Confirmed Cases versus the Number of Infected, but Non-Detected, Cattle to Assess Confidence in Freedom from Infection.

Quantitative risk assessments for Bovine spongiform encephalopathy (BSE) necessitate estimates for key parameters such as the prevalence of infection, the probability of absence of infection in defined birth cohorts, and the numbers of BSE-infected, but non-detected cattle entering the food chain. We estimated three key parameters with adjustment for misclassification using the German BSE surveillance data using a Gompertz model for latent (i.e., unobserved) age-dependent detection probabilities and a Poisson response model for the number of BSE cases for birth cohorts 1999 to 2015. The models were combined in a Bayesian framework. We estimated the median true BSE prevalence between 3.74 and 0.216 cases per 100,000 animals for the birth cohorts 1990 to 2001 and observed a peak for the 1996 birth cohort with a point estimate of 16.41 cases per 100,000 cattle. For birth cohorts ranging from 2002 to 2013, the estimated median prevalence was below one case per 100,000 heads. The calculated confidence in freedom from disease (design prevalence 1 in 100,000) was above 99.5% for the birth cohorts 2002 to 2006. In conclusion, BSE surveillance in the healthy slaughtered cattle chain was extremely sensitive at the time, when BSE repeatedly occurred in Germany (2000–2009), because the entry of BSE-infected cattle into the food chain could virtually be prevented by the extensive surveillance program during these years and until 2015 (estimated non-detected cases/100.000 [95% credible interval] in 2000, 2009, and 2015 are 0.64 [0.5,0.8], 0.05 [0.01,0.14], and 0.19 [0.05,0.61], respectively).

Animal prion diseases: A review of intraspecies transmission.

Animal prion diseases are a group of neurodegenerative, transmissible, and fatal disorders that affect several animal species. The causative agent, prion, is a misfolded isoform of normal cellular prion protein, which is found in cells with higher concentration in the central nervous system. This review explored the sources of infection and different natural transmission routes of animal prion diseases in susceptible populations. Chronic wasting disease in cervids and scrapie in small ruminants are prion diseases capable of maintaining themselves in susceptible populations through horizontal and vertical transmission. The other prion animal diseases can only be transmitted through food contaminated with prions. Bovine spongiform encephalopathy (BSE) is the only animal prion disease considered zoonotic. However, due to its inability to transmit within a population, it could be controlled. The emergence of atypical cases of scrapie and BSE, even the recent report of prion disease in camels, demonstrates the importance of understanding the transmission routes of prion diseases to take measures to control them and to assess the risks to human and animal health.

Potential BSE risk posed by the use of ruminant collagen and gelatine in feed for non-ruminant farmed animals.

EFSA was requested to estimate the cattle bovine spongiform encephalopathy (BSE) risk (C‐, L‐ and H‐BSE) posed by ruminant collagen and gelatine produced from raw material fit for human consumption, or from material classified as Category 3 animal by‐products (ABP), to be used in feed intended for non‐ruminant animals, including aquaculture animals. Three risk pathways (RP) were identified by which cattle could be exposed to ruminant feed cross‐contaminated with ruminant collagen or gelatine: 1) recycled former foodstuffs produced in accordance with Regulation (EC) No 853/2004 (RP1), 2) technological or nutritional additives or 3) compound feed, produced either in accordance with Regulation (EC) No 853/2004 (RP2a) or Regulation (EU) No 142/2011 (RP2b). A probabilistic model was developed to estimate the BSE infectivity load measured in cattle oral ID 50 (CoID 50)/kg, in the gelatine produced from the bones and hide of one infected animal older than 30 months with clinical BSE (worst‐case scenario). The amount of BSE infectivity (50th percentile estimate) in a member state (MS) with negligible risk status was 7.6 × 10–2 CoID 50/kg, and 3.1 × 10–4 CoID 50/kg in a MS with controlled risk status. The assessment considered the potential contamination pathways and the model results (including uncertainties) regarding the current epidemiological situation in the EU and current statutory controls. Given the estimated amount of BSE infectivity to which cattle would be exposed in a single year, and even if all the estimated undetected BSE cases in the EU were used for the production of collagen or gelatine (either using raw materials fit for human consumption or Category 3 ABP raw materials), it was concluded that the probability that no new case of BSE in the cattle population would be generated through any of the three RP is 99–100% (almost certain).

Life under Extreme Conditions: Aeropyrum pernix and Pernisine

Life under Extreme Conditions: Aeropyrum pernix and Pernisine

The European Union summary report on surveillance for the presence of transmissible spongiform encephalopathies (TSE) in 2018.

This report presents the results of surveillance on transmissible spongiform encephalopathies (TSE) in bovine animals, sheep, goats, cervids and other species, and genotyping in sheep, carried out in 2018 by 28 Member States (MS) according to legislation, and by Iceland, North Macedonia, Norway and Switzerland (non‐MS). In total, 1,181,934 cattle were tested by MS, a 10% decrease from 2017 and 20,402 by the four non‐MS. One case of classical bovine spongiform encephalopathy (BSE) was reported in 2018 by the UK, born after the enforcement of the total feed ban. Three atypical BSE cases (2 L‐type/1 H‐type) were reported by France. Over the year, a total of 325,386 sheep and 138,128 goats were tested in the EU, an increase of 3.4% and 17.8%, respectively, compared to 2017. In sheep, 934 cases of scrapie were reported: 821 classical (99 index cases and 97.8% with genotypes of susceptible groups) by 7 MS and 113 atypical (105 index cases) by 14 MS. Twenty‐nine ovine scrapie cases were reported by Iceland and Norway. Random genotyping was only reported by eight MS and after excluding Cyprus showed that 18.7% of the genotyped sheep carried genotypes of the susceptible groups. In goats, 523 cases of scrapie were reported: 517 classical (38 index cases) by seven MS and six atypical (all index cases) by four MS. The heterogenous enforcement of a 3‐year surveillance programme for chronic wasting disease (CWD) from 1/1/2018 in six MS (Estonia, Finland, Latvia, Lithuania, Poland and Sweden) resulted in the testing of 5,110 cervids and the confirmation of the first case of CWD in the EU: a wild moose in Finland. Other six MS tested 3,075 cervids with no positive results. Norway tested 33,037 cervids in 2018, resulting in seven new cases: six reindeer and one moose. In total, 105 animals from three other species were tested by two MS, with negative results.

Survey of animal by-products in feedingstuffs before the reintroduction of processed animal proteins in aquafeed

Description. Since 2001, the number of bovine spongiform encephalopathy cases has drastically declined. A gradual lifting of the feed ban for aquaculture was possible in 2013 but this partial relaxation makes its control much more complex. Objectives. The objective was to have a practical overview of the current analytical situation and to highlight current and foreseen analytical gaps in the context of a progressive lifting of the ban. Method. Feed samples, collected before the partial lifting as regards aquafeed in 2013, were firstly analyzed by light microscopy. All samples were additionally analyzed by PCR in order to study the difficulties which would be faced with feeds produced after the relaxation. ELISA for the detection of milk proteins was also performed on samples in which ruminant DNA was detected. Results. When keeping the interpretation to the sole light microscopy results, all samples were in accordance to the legal requirements. Adding the PCR results made the interpretation more difficult. DNA of terrestrial animals was detected in nearly 65% of the samples. Apart from aquafeeds, the presence of ruminant DNA could be explained by the use of dairy products confirmed in most cases by ELISA. In aquafeeds, 23% (13/57) of the samples tested positive for ruminant DNA but only three of them also tested positive for milk proteins. Conclusions. The study underlined the crucial need for complementary analytical solutions in order to identify the source of the detected DNA.

The European Union summary report on surveillance for the presence of transmissible spongiform encephalopathies (TSEs) in 2017.

This report presents the results of surveillance on transmissible spongiform encephalopathies (TSEs) in bovine animals, sheep, goats, cervids and other animal species, as well as genotyping in sheep, carried out in 2017 in the European Union (EU) according to Regulation (EC) 999/2001, and in Iceland, Norway and Switzerland. In total, 1,312,714 cattle were tested by the 28 EU Member States (MSs) which is a decrease of 3% compared with 2016; 18,526 were tested by the three non‐MSs. For the first time since bovine spongiform encephalopathy (BSE) has been reported, no cases of classical BSE were reported in 2017. Six atypical BSE cases were reported by three different MSs: Spain 1 H‐BSE/2 L‐BSE; France 1 H‐BSE/1 L‐BSE; and Ireland 1 L‐BSE. Over the year, 314,547 sheep and 117,268 goats were tested in the EU. In sheep, 933 cases of scrapie were reported: 839 classical and unknown (145 index cases) by eight MSs and 94 atypical (89 index cases) by 13 MSs. Fourteen ovine scrapie cases were reported by Iceland and Norway. Of all classical scrapie cases, 98.2% occurred in sheep with genotypes of susceptible groups. The genotyping of a random sample in 21 MSs showed that 26.5% of the genotyped sheep carried genotypes of the susceptible groups. In goats 567 cases of scrapie were reported: 558 classical (42 index cases) by seven MSs and nine atypical (seven index cases) by five MSs. In total, 3,585 cervids were tested for TSE by ten MSs, mostly by Romania. All results were negative. Eleven cases of chronic wasting disease (CWD) cases were reported in cervids by Norway: nine wild reindeer, one moose and, for the first time ever, one red deer. In total, 185 animals from five species other than cattle, small ruminants and cervids were tested by three MSs, with negative results.

Thermodynamic characterization for the denatured state of bovine prion protein and the BSE Associated variant E211K

ABSTRACTPropagation of transmissible spongiform encephalopathies involves the conversion of cellular prion protein, PrPC, into a misfolded oligomeric form, PrPSc. The most common hereditary prion disease is a genetic form of Creutzfeldt-Jakob disease in humans, in which a mutation in the prion gene results in a glutamic acid to lysine substitution at position 200 (E200K) in PrP. In cattle, the analogous amino acid substitution is found at residue 211 (E211K) and has been associated with a case of bovine spongiform encephalopathy. Here, we have compared the secondary structure of E211K to that of wild type using circular dichroism and completed a thermodynamic analysis of the folding of recombinant wild type and E211K variants of the bovine prion protein. The secondary structure of the E211K variant was essentially indistinguishable from that of wild type. The thermodynamic stability of E211K substitution showed a slight destabilization relative to the wild type consistent with results reported for recombinant human prion protein and its mutant E200K. In addition, the E211K variant exhibits a similarly compact denatured state to that of wild type based upon similar m-value and change in heat capacity of unfolding for the proteins. Together these results indicate that residual structure in the denatured state of bPrP is present in both the wild type protein and BSE associated variant E211K. Given this observation, as well as folding similarities reported for other disease associated variants of PrP it is worth consideration that functional aspects of PrP conformation may play a role in the misfolding process.

Updated quantitative risk assessment (QRA) of the BSE risk posed by processed animal protein (PAP).

EFSA was requested: to assess the impact of a proposed quantitative real‐time polymerase chain reaction (qPCR) ‘technical zero’ on the limit of detection of official controls for constituents of ruminant origin in feed, to review and update the 2011 QRA, and to estimate the cattle bovine spongiform encephalopathy (BSE) risk posed by the contamination of feed with BSE‐infected bovine‐derived processed animal protein (PAP), should pig PAP be re‐authorised in poultry feed and vice versa, using both light microscopy and ruminant qPCR methods, and action limits of 100, 150, 200, 250 and 300 DNA copies. The current qPCR cannot discriminate between legitimately added bovine material and unauthorised contamination, or determine if any detected ruminant material is associated with BSE infectivity. The sensitivity of the surveillance for the detection of material of ruminant origin in feed is currently limited due to the heterogeneous distribution of the material, practicalities of sampling and test performance. A ‘technical zero’ will further reduce it. The updated model estimated a total BSE infectivity four times lower than that estimated in 2011, with less than one new case of BSE expected to arise each year. In the hypothetical scenario of a whole carcass of an infected cow entering the feed chain without any removal of specified risk material (SRM) or reduction of BSE infectivity via rendering, up to four new cases of BSE could be expected at the upper 95th percentile. A second model estimated that at least half of the feed containing material of ruminant origin will not be detected or removed from the feed chain, if an interpretation cut‐off point of 100 DNA copies or more is applied. If the probability of a contaminated feed sample increased to 5%, with an interpretation cut‐off point of 300 DNA copies, there would be a fourfold increase in the proportion of all produced feed that is contaminated but not detected.

Presumptive BSE cases with an aberrant prion protein phenotype in Switzerland, 2011: Lack of prion disease in experimentally inoculated cattle and bovine prion protein transgenic mice.

Bovine spongiform encephalopathy (BSE) is caused by different prion strains that are discriminated by the molecular characteristics of the pathological prion protein. In 2011, Switzerland reported two presumptive cases of BSE in cattle with a prion protein phenotype different from previously described strains, and it was unclear whether these findings were related to a transmissible disease and have implications on animal and public health. In this study, brain tissues of these cases were inoculated into transgenic mice expressing the bovine prion protein (BoPrP-Tg110) and into cattle. Clinical and pathological investigations as well as molecular testing did not provide evidence for the presence of BSE in the Swiss cases after two passages in BoPrP-Tg110 mice and a challenge period of 3.5years in cattle. This lack of disease transmission suggests that the Swiss 2011 cases were not affected by a prion disease and were unrelated to the feed-born BSE epidemic.

Experimental sheep BSE prions generate the vCJD phenotype when serially passaged in transgenic mice expressing human prion protein

The epizootic prion disease of cattle, bovine spongiform encephalopathy (BSE), causes variant Creutzfeldt-Jakob disease (vCJD) in humans following dietary exposure. While it is assumed that all cases of vCJD attributed to a dietary aetiology are related to cattle BSE, sheep and goats are susceptible to experimental oral challenge with cattle BSE prions and farmed animals in the UK were undoubtedly exposed to BSE-contaminated meat and bone meal during the late 1980s and early 1990s. Although no natural field cases of sheep BSE have been identified, it cannot be excluded that some BSE-infected sheep might have entered the European human food chain. Evaluation of the zoonotic potential of sheep BSE prions has been addressed by examining the transmission properties of experimental brain isolates in transgenic mice that express human prion protein, however to-date there have been relatively few studies. Here we report that serial passage of experimental sheep BSE prions in transgenic mice expressing human prion protein with methionine at residue 129 produces the vCJD phenotype that mirrors that seen when the same mice are challenged with vCJD prions from patient brain. These findings are congruent with those reported previously by another laboratory, and thereby strongly reinforce the view that sheep BSE prions could have acted as a causal agent of vCJD within Europe.

1. Economic Impacts of Bovine Spongiform Encephalopathy in Canada and Europe And The Effect of Compensation Programs

Before the first domestic case of bovine spongiform encephalopathy (BSE) was identified in May 2003, Canada was the world’s third largest exporter of cattle behind the United States (U.S.) and Australia. After the BSE disclosure, the U.S. and 40 other countries imposed an immediate ban on imported Canadian beef and cattle products. The interdependence of the Canadian beef industry with that of the U.S. prior to the outbreak of BSE was a critical factor in Canada’s market vulnerability and the resulting economic impact. As the re-opening of the U.S. border was prolonged, beef producers adopted a variety of strategies to deal with the loss of income including refinancing existing loans and selling land or other assets. However these measures taken by individual farmers were not sufficient in completely supplementing their loss of income, thus creating a need for government funding and support. Little research has been done to assess the impact of government subsidies as a tool to offset the economic losses incurred by BSE. The analysis of the impacts of BSE and the resulting subsidies is extended to Britain, France, Germany and the European Union to see if government subsidies had a similar impact as compared to Canada. Analysis of existing literature shows the economic impacts to be heavily impacted by the structure of the beef industry and the subsidies to be impacted by consumption levels. The result of the subsidies is unclear; however due to lack of recent information the full analysis of the result of subsidy programs is difficult to determine.

Using an epidemiological framework and bovine spongiform encephalopathy investigation questionnaire to investigate suspect bovine spongiform encephalopathy cases: an example from a bovine spongiform encephalopathy case in Ireland in 2015

In several EU member states, bovine spongiform encephalopathy (BSE) cases have been identified in cattle born after the reinforced ban (BARB cases), for reasons that are not entirely clear. Epidemiological...

The European Union summary report on surveillance for the presence of transmissible spongiform encephalopathies (TSE) in 2016.

This report presents the results of surveillance activities on transmissible spongiform encephalopathies (TSEs) in bovine animals, sheep, goats, cervids and other species, as well as genotyping data in sheep, carried out in 2016 in the European Union according to Regulation (EC) 999/2001, and in Iceland, Norway and Switzerland. In 2016, 1,352,585 bovine animals were tested in the European Union (5% less than in 2015). For the first time, the United Kingdom did not report any case of bovine spongiform encephalopathy (BSE), whereas France reported one classical and three atypical cases (H), and Spain one atypical case (H). The classical BSE case was born after the enforcement of the total EU‐wide feed ban in 2001 (BARB case). In 2016, 286,351 sheep and 110,832 goats were tested (5% and 11% less than in 2015, respectively). Sheep scrapie was reported by 20 Member States (MSs) (685 cases) and goat scrapie by 9 MSs (634 cases). A total of 25 ovine scrapie cases were reported by Iceland and Norway. At the EU level, the occurrence of scrapie in small ruminants remains stable, with classical scrapie (1,175 cases) being reported more frequently than atypical scrapie (135 cases). A total of 97.2% of the classical scrapie cases in sheep occurred in animals with genotypes belonging to the susceptible group, and a random sampling showed that 26.6% of the genotyped sheep held genotypes of the susceptible group (excluding Cyprus). In 2016, five cases of chronic wasting disease were reported in cervids by Norway: three in wild reindeer and two in moose. It was the first time that this disease is reported in Europe. A total of 2,712 cervids were tested for TSEs in seven different member states, 90% of them in Romania, with negative results. A total of 490 animals from other non‐ruminant species were tested in four different member states, with negative results.

Media Cultures and the Representation of Science in Korea and the United States: The BSE Case in 2008

In 2008 the Korean government decided to resume importing US beef, leading to a nationwide controversy over the risk of bovine spongiform encephalopathy (BSE), or mad cow disease. Korean media coverage of BSE during this controversy demonstrates how media reporting on scientific matters interacts with political controversy over science-related risks. In Korea, where media organizations tend to be associated with particular political ideologies, the media emphasized the uncertainty of scientific accounts in the BSE case and reinforced the politicization of science by selectively mobilizing contrasting scientific claims and scientific authorities based on each media outlet's political position. The distinctive role of such a media culture in the science-related political discourse is further highlighted when we consider US media coverage of BSE risk during the same period: in that coverage, the baseline technical risk-related issues were taken for granted and the BSE controversy in Korea was presented largely as a trade issue.

Bovine spongiform encephalopathy (BSE) cases born after the total feed ban.

Sixty bovine spongiform encephalopathy (BSE) cases of Classical or unknown type (BARB‐60 cases) were born after the date of entry into force of the EU total feed ban on 1 January 2001. The European Commission has requested EFSA to provide a scientific opinion on the most likely origin(s) of these BARB‐60 cases; whether feeding with material contaminated with the BSE agent can be excluded as the origin of any of these cases and, if so, whether there is enough scientific evidence to conclude that such cases had a spontaneous origin. The source of infection cannot be ascertained at the individual level for any BSE case, including these BARB‐60 cases, so uncertainty remains high about the origin of disease in each of these animals, but when compared with other biologically plausible sources of infection (maternal, environmental, genetic, iatrogenic), feed‐borne exposure is the most likely. This exposure was apparently excluded for only one of these BARB‐60 cases. However, there is considerable uncertainty associated with the data collected through the field investigation of these cases, due to a time span of several years between the potential exposure of the animal and the confirmation of disease, recall difficulty, and the general paucity of documented objective evidence available in the farms at the time of the investigation. Thus, feeding with material contaminated with the BSE agent cannot be excluded as the origin of any of the BARB‐60 cases, nor is it possible to definitively attribute feed as the cause of any of the BARB‐60 cases. A case of disease is classified as spontaneous by a process of elimination, excluding all other definable possibilities; with regard to the BARB‐60 cases, it is not possible to conclude that any of them had a spontaneous origin.

Is there a decline in bovine spongiform encephalopathy cases born after reinforced feed bans? A modelling study in EU member states.

Occasional cases of classical bovine spongiform encephalopathy (BSE) still continue to occur within the European Union (EU) for animals born after reinforced feed bans (BARBs), which should in theory have eliminated all risk of infection. The study aimed to determine (i) whether a common rate of decline of BSE infection was evident across EU member states, i.e. to determine whether control measures have been equally effective in all member states, (ii) whether there was any evidence of spontaneous occurrence of BSE in the data and (iii) the expected date for the last BSE case in UK. It was found that there was no significant difference in the rate of decline of BSE prevalence between member states, with a common rate of decline of 33·9% per annum (95% CI 30·9-37%) in successive annual birth cohorts. Trend analysis indicated an ultimate decline to 0 prevalence, suggesting that spontaneous occurrence does not explain the majority of cases. Projecting forward the trends from the back-calculation model indicated that there was approximately a 50% probability of further cases in the UK, and should the current rate of decline continue, there remains the possibility of further occasional cases up until 2026.

Geographic exposure risk of variant Creutzfeldt-Jakob disease in US blood donors: a risk-ranking model to evaluate alternative donor-deferral policies.

Variant Creutzfeldt-Jakob disease (vCJD) has been transmitted by blood transfusion (TTvCJD). The US Food and Drug Administration (FDA) recommends deferring blood donors who resided in or traveled to 30 European countries where they may have been exposed to bovine spongiform encephalopathy (BSE) through beef consumption. Those recommendations warrant re-evaluation, because new cases of BSE and vCJD have markedly abated. The FDA developed a risk-ranking model to calculate the geographic vCJD risk using country-specific case rates and person-years of exposure of US blood donors. We used the reported country vCJD case rates, when available, or imputed vCJD case rates from reported BSE and UK beef exports during the risk period. We estimated the risk reduction and donor loss should the deferral be restricted to a few high-risk countries. We also estimated additional risk reduction by leukocyte reduction (LR) of red blood cells (RBCs). The United Kingdom, Ireland, and France had the greatest vCJD risk, contributing approximately 95% of the total risk. The model estimated that deferring US donors who spent extended periods of time in these three countries, combined with currently voluntary LR (95% of RBC units), would reduce the vCJD risk by 89.3%, a reduction similar to that achieved under the current policy (89.8%). Limiting deferrals to exposure in these three countries would potentially allow donations from an additional 100,000 donors who are currently deferred. Our analysis suggests that a deferral option focusing on the three highest risk countries would achieve a level of blood safety similar to that achieved by the current policy.

Evaluation of rapid post-mortem test kits for bovine spongiform encephalopathy (BSE) screening in Japan: Their analytical sensitivity to atypical BSE prions

ABSTRACTA classical type of bovine spongiform encephalopathy (C-BSE), recognized in 1987, had a large impact on public health due to its zoonotic link to variant Creutzfeldt-Jakob disease by the human consumption of dietary products contaminated with the C-BSE prion. Thus, a number of countries implemented BSE surveillance using rapid post-mortem test kits that were approved for detection of the C-BSE prion in the cattle brain. However, as atypical BSE (L- and H-BSE) cases emerged in subsequent years, the efficacy of the kits for the detection of atypical BSE prions became a matter of concern. In response to this, laboratories in the European Union and Canada evaluated the kits used in their countries. Here, we carried out an evaluation study of NippiBL®, a kit currently used for BSE screening in Japan. By applying the kit to cattle brains of field cases of C-BSE and L-BSE, and an experimental case of H-BSE, we showed its comparable sensitivities to C, L-, and H-BSE prions, and satisfactory performance required by the European Food Safety Authority. In addition to NippiBL®, two kits (TeSeE® and FRELISA®) formerly used in Japan were effective for detection of the L-BSE prion, although the two kits were unable to be tested for the H-BSE prion due to the discontinuation of domestic sales during this study. These results indicate that BSE screening in Japan is as effective as those in other countries, and it is unlikely that cases of atypical BSE have been overlooked.