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From: TSS ()
Subject: BSE REPORT APRIL 2005
Date: September 6, 2005 at 8:57 am PST

for all consumers

BSE

REPORT

April 2005

Featuring:

. Science news

. General news

. Official figures

>

BSE monthly report is compiled during the week following the month of

the report. Material is collected from news reports, science abstracts and

government sources, and is presented in good faith. However, Which?

cannot guarantee the accuracy of the information and does not necessarily

hold any of the opinions reported here.

Readers are welcome to send correspondence to the editor at

BSEREPORT@which.co.uk or by post to BSE monthly report, Policy

Department, Which?, 2 Marylebone Road, London NW1 4DF.

Science news

Fragments of scrapie prion can self-replicate in test-tube

Recent research has shown that truncated sections of the amyloid form of

recombinant prion protein (PrP) encompassing residues 89-230 produced in test

tubes can induce transmissible prion disease in mice (see January 2005 BSE monthly

report). New research has now shown that these forms of prion are more

proteinase-K sensitive but contain a proteinase K-resistant core composed only of

residues 152/153-230 and 162-230.1 These PK-resistant fragments are similar to

those observed upon PK digestion of a minor subpopulation of PrPSc recently

identified in patients with sporadic CJD (sCJD).

Remarkably, this core is sufficient for self-propagating activity in test-tubes, and

preserves its beta-sheet-rich fibrillar structure. Furthermore, full-length

recombinant PrP 23-230 when replicated in the test tube generates two distinct

subpopulations of amyloid: one is similar to the minor subspecies of PrPSc, and the

other to classical PrPSc. Since no cellular factors or templates were used for

generation of the amyloid fibrils, the authors suggest that formation of the

subpopulation of PrPSc with a short PK-resistant C-terminal region reflects an

intrinsic property of PrP rather than the influence of cellular environments and/or

cofactors.

Experimentally-misfolded prions cause disease

A further series of experiments has confirmed the ability of prions to transmit

disease in isolation of other agents, with evidence that artificially misfolded prions

can cause scrapie-like diseases when inoculated into test animals. Researchers in

Texas have shown that the conversion of purified normal cellular prions PrPC into

abnormal prions PrPres can be mimicked in test tubes using cyclic amplification

techniques, giving rise to indefinite amplification of PrPres.2 The syntheticallygenerated

forms of PrPres share similar biochemical and structural properties with

PrPres derived from scrapie-infected brains. Inoculation of wild-type hamsters with

the synthetically produced PrPres led to a scrapie disease identical to the illness

produced by infectious material from brain. These findings, say the authors,

demonstrate that prions can be generated synthetically and provide strong

evidence in support of the prion-only hypothesis of disease transmission.

GM mice can distinguish prion strains

Genetically modified mice with genes able to express bovine prions have been

developed in the laboratories of Nobel prize-winning scientist Stanley Prusiner.3

These mice show no apparent species barrier to BSE, with similar incubation times

on first and second passaging of the disease. The mice also posed no transmission

barrier for scrapie prions derived from Suffolk sheep, suggesting that cattle may be

highly susceptible to some sheep scrapie strains.

Furthermore, the mice were also found to be susceptible to prions from humans

with variant CJD, although some species barrier appeared to be present, with

incubation times shortened by 30 to 40 days on second passage. In contrast, the GM

mice were not susceptible to sporadic, familial, or iatrogenic CJD prions.

The structural stability of prions derived from cattle with BSE and from the GM

bovine-mice with BSE were similar. The stability of sheep scrapie prions was higher

than that found for the BSE prions but lower if the scrapie prions were passaged in

2

the GM mice. These findings suggest that BSE prions did not arise from a sheep

scrapie strain like the one described here; rather, BSE prions may have arisen

spontaneously in a cow or by passage of a different scrapie strain that maintains its

stability upon passage in cattle.

The authors suggest that it may be possible to distinguish BSE prions from scrapie

strains in sheep by combining stability studies with studies using novel GM mice

expressing a mixed mouse-bovine prion-encoding gene. Single-amino-acid

substitutions in such mixed genes have produced large changes in incubation times

that allowed the researchers to distinguish prions causing BSE from those causing

scrapie, they state.

Cellular prions detectable in urine

A research team in Cleveland, USA, led by Dr Harash Narang, has demonstrated

that normal cellular prions can be detected in human urine. The method "can

easily and reliably" detect PrPC in apparently healthy individuals using less than 1

ml of urine.4 The amount of urinary PrPC is estimated to be in the range of several

micrograms/litre. Dr Narang previously attempted to undertake research in

Newcastle, UK, on the detection of BSE in urine, but research funding was

withdrawn in the late 1990s in a move that caused some controversy at the time.5

Mouse prion infection is seen in spleen before brain

An investigation of prion infection in mice by Japanese researchers has shown that

the accumulation of the abnormal form of prion protein (PrPSc) in spleens occured

far in advance of its accumulation in brains, whether the infection was initially

administered through feeding, through injection into the abdomen (peritoneum) or

injection directly into the brain.6 Using Western blotting with anti-prion protein

antibodies, accumulation of PrPSc was first detected in the spleen on the 70th day

after inoculation directly into the brain, and detected in the brain on the 116th day.

Inoculation through the other routes took much longer to show the presence of

PrPSc in either the spleen or brain (see table) but the spleen showed an

accumulation of PrPSC at least 130 days in advance of it being detected in the

brain. These results indicate that PrPSc increases rapidly in the spleen compared

with the brain in a manner independent of the inoculation route.

Number of days after inoculation with scrapie prion

Inoculation route

cerebral peritone

al

oral

First detected in spleen 70 94 93

Maximum reached in spleen 116 94 93

First detected in brain 116 231 259

Maximum reached in brain 152 >231 >259

VLA provides kit to distinguish BSE from scrapie

A discriminatory diagnostic kit to distinguish between scrapie and BSE in sheep has

recently been launched by the Veterinary Laboratories Agency (VLA).7 Under EU

legislation all samples from small ruminants that are positive for a TSE on rapid

testing should be further screened using an approved discriminatory method to

determine if BSE is present. Several methods have been evaluated and approved.

The method developed by the VLA uses protein extraction and Western blotting

3

techniques to differentiate between scrapie and BSE. The new kit is a modified

version of the Prionics-Check technique and is reported to provide ‘a cleaner, more

defined signal of the abnormal prion protein profile' for analysis.

Single use surgical instruments vary in quality

Research undertaken to assess the quality and consistency of single-use

adenotonsillectomy instruments available in the UK in comparison with reusable

instruments has shown that the single-use instruments may vary in quality, with

some samples proving to be significantly inferior to re-usable instruments.8 (This

research study was presented at a SEAC meeting, March 2005.9)

Following a detailed specification for single-use instruments, a surveillance system

monitored the performance of samples of single use instruments in terms of the

numbers of instruments from each set judged as unacceptable or as good as the

original, and the number and cause of instrument failure during clinical

surveillance. Between 40% and 93% of the instruments on each set were as good as

the original and between 0% and 40% of the instruments were unacceptable, out of

six sets of steel and one set of polymer instruments. Over 4000 procedures were

monitored during 2003-2004 using a total of over 40,000 instruments. Problems

were reported with 335 (0.8%) instruments, 46% attributable to instrument design,

14% to poor design control and 13% to instruments escaping quality control systems.

Following correction of the faults, a survey in 2004 found the problem rate had

fallen to 0.4%.

The research team, in Wales, UK, concluded that high quality single-use

instruments for tonsil and adenoid surgery are available in the UK, but that some

companies offered inferior instruments not fit for their purpose. The procurement,

introduction and subsequent clinical approval of single-use instruments requires a

radically different approach to that currently applied to the purchase of reusable

surgical equipment, they say. Careful monitoring of their introduction is essential.

Disposable optical instruments carry bacteria

In order to determine the pressure inside the eyeball, a small flat disk – an

applanation tonometer – needs to be applied to the cornea. Due to the theoretical

possibility of prion transmission in applanation tonometry, many ophthalmological

units in the United Kingdom now use disposable tonometer prisms, but an

investigation of the way in which these are applied suggest that they may become

contaminated with bacteria before touching the eye.10

A questionnaire of staff revealed that almost 50% admitted touching the

applanating face of the tonometer prism prior to applanation. Cultures of the

prisms grew a range of bacteria including Staphylococcus epidermidis,

Staphylococcus aureus, and Bacillus species. The results suggested that adenovirus

could also be transmitted by applanation tonometry. The research team concluded

that the use of disposable prisms may reduce the risk of prion transmission but is

not bacteriologically or virologically aseptic. This is a potential infection risk to

patients.

Details given of French case of BSE in farm goat

The Veterinary Record has published further details of the case of a goat tested

under the surveillance programme and found to have BSE and not scrapie as first

assumed when it was slaughtered in 2002.11 The case was found as part of a survey

4

re-assessing the cases of TSE, and consisting of seven French laboratories analysing

438 brain samples of suspected scrapie cases in sheep and goats, including 216

samples collected in 1990, 135 samples collected in 2002 and 87 cases collected in

2003.

Three different Western blot tests and one ELISA test were conducted

independently in four different laboratories, with each sample tested by at least

three of the four tests. For one goat sample (CH636), the four tests provided

convergent results, which were indistinguishable from those obtained with a

control sample from an animal experimentally infected with BSE. When the brain

extract was inoculated by the intracerebral route into four strains of wild-type

mice, incubation times were all compatible with those recorded for experimental

sheep BSE, and the lesion profile was identical to the profile characteristic of BSE

in sheep.

The researchers note that it is impossible to conclude whether the origin of the

disease n the goat was linked to BSE-contaminated feed, or whether it reflects the

presence of this strain of TSE in goats preceding the emergence of BSE in cattle.

Nevertheless, they warn, the presence of this strain in a goat underscores the need

to reassess the risks to human health linked to the consumption of small ruminant

products.

Sheep bred for hill farming most at risk of scrapie

A large-scale survey of British sheep, involving 250,000 animals tested under the

National Scrapie Plan between October 2001 and January 2003, has provided

comprehensive data on the prevalence of scrapie resistant genotypes in 38

different breeds.12 The results showed marked variability among the genotype

profiles of the different breeds, but several trends emerged. A comparison of the

allele frequencies demonstrated that the breeds could be grouped into three

categories: breeds dominated by ARR and ARQ in which the frequency of ARR

exceeded the frequency of ARQ; breeds dominated by ARR and ARQ in which the

frequency of ARQ exceeded the frequency of ARR; and breeds with significant

levels of either AHQ, ARH or VRQ.

Hill breeds were more likely to have a lower proportion of animals at low risk of

scrapie (NSP type 1) and a higher proportion of animals at an intermediate risk of

scrapie (NSP type 3) than other breeds. Most breeds had a small proportion of

animals at high risk of scrapie (NSP type 5). The frequency of ARR/VRQ (NSP type

4) was variable.

Sheep tongues infective in scrapie-infected animals

The presence of infectivity in the tongues of animals infected with scrapie has been

shown following either oral or intracranial inoculation with scrapie and with

transmissible mink encephalopathy derived from laboratory rodents. A brief report

from researchers in Turin, Italy, has stated that they have found scrapie-like prions

in the tongues of seven scrapie-infected sheep, based on immunohistochemistry

and Western blotting.13

Sheep blood tested for prion-carrying cells

The blood of sheep infected with TSEs is known to carry infectivity. In an

assessment of which cells may be most responsible for carrying this infectivity,

researchers examined the expression of normal cellular prion (PrPC) in a variety of

5

sheep with different genetic resistance to scrapie.14 Expression of PrPC on the

surfaces of cells was found only on peripheral blood mononuclear cells (PBMCs)

although significant amounts of PrPC were found within platelet cells. The level of

PrPC expressed on the cell surface of PBMCs was influenced by the scrapie-resistant

genotype, with the highest levels found in scrapie-susceptible VRQ/VRQ sheep and

the lowest levels in scrapie-resistant ARR/ARR sheep. In susceptible sheep, PrPC

was expressed at varying levels on all major subsets of PBMCs, with the highest

levels being found on the CD21(+) subset of B cells – and the level of expression was

increased dramatically on these cells in some scrapie-infected sheep.

Brain tissue may still be entering food supply

Previous studies have demonstrated a potential risk of carcase contamination with

brain tissue following the use of captive bolt gun stunning in cattle. A new study

has now explored these findings in regard to the captive bolt guns currently in use

in the United Kingdom.15 The research team, at Bristol University, found brain

tissue fragments or elevated levels of a marker protein for brain tissue in venous

blood samples from 4% (95% likelihood: 1.6% to 9.8%) of cattle stunned by

penetrating captive bolt gun and from 2% (95% likelihood: 0.6% to 7%) of those

stunned by the supposedly safer non-penetrating captive bolt gun. These methods

of slaughter may give rise to Specified Risk Material entering the food supply.

New antibodies may detect beef brain in cooked meats

Because bovine central nervous tissue (CNT) is the main risk material in

transmission of BSE, a test is needed to enforce the ban on CNT in human

foodstuffs in many countries, including in the United States and the European

Union. A German research team have used immunohistochemistry and Western

blots with antibodies against glial fibrillary acidic protein (GFAP) and myelin basic

protein (MBP), which are both resistant to processing methods used for meat

products.16 The anti-GFAP antibody showed a high degree of tissue specificity,

whereas the anti-MBP antibody had high species specificity, clearly differentiating

between porcine and bovine CNT Therefore, say the researchers, immunochemistry

performed with both antibodies in tandem could provide an effective means for

detecting bovine CNT in meat products.

Feline TSE: no hidden cases during the 1990s

A survey of brain tissue from 192 cats with neurological signs has been undertaken

to determine the prevalence of feline spongiform encephalopathy (FSE) during the

peak of the disease during the early 1990s.17 Defra disease records show 81

reported cases of FSE in Great Britain, all recorded in the period 1990-1997. The

research paper suggests that 89 cases were recorded in Great Britain and the

Channel Islands since 1990, with single cases recorded in the years 1998-2001, and

none since then. The present survey was based on animals referred to government

veterinary laboratory services in the period 1990-1997.

All cats were referred as suspected FSE, and originated in Great Britain apart from

one sample from Norway. Prior to an animal’s death, the most commonly recorded

clinical signs were ataxia, behavioural changes and epilepsy. All samples were

examined histologically, and tissues from 173 of them were later examined

immunohistochemically.

6

The results showed that none of the cats had histopathological evidence of FSE, but

abnormal prion protein was observed in one of the cats examined by

immunohistochemistry. Among the remaining cats, the most common findings were

non-suppurative encephalomyelitis in 28 per cent, neoplasia in 15 per cent and a

heterogeneous group of degenerative encephalopathies in 9 per cent of the cats.

Statistical estimates put low risk on incinerator waste

Researchers in Denmark have estimated that very low levels of infectivity would be

found in the ash residues left after incineration of cattle meat and bone meal.18 At

present, MBM is commonly incinerated in cement works or coal-fired power plants

and the ashes and slag are incorporated into the cement or concrete. Using a

statistical simulation model, the BSE risk to cattle and humans posed by the ash

and slag was estimated, assuming that all specified risk material (SRM) and MBM

produced in Denmark would be incinerated in a single gas-fired power plant

operating at 850 degrees C. Assuming the incinerator handled up to six cases of

BSE, and up to 31 carcasses or SRM from undetected BSE cases, then if the slag/ash

was collected and re-incinerated for use in building material the resulting ash

would contain less than one billionth of an infectious dose.

Potentially infective tonsil tissue in cattle tongues

Previous studies have shown that traces of infectivity were found in the palatine

tonsil of cattle killed 10 months after exposure to BSE. Because the infectivity may

therefore be present throughout the tonsils in cattle infected with BSE,

observations have been made of the anatomical and histological distribution of

tonsil tissue in the root of the tongue of cattle.19 Examinations of tongues derived

from abattoirs in Britain showed that identifiable tonsillar tissue was present in

more than 75 per cent of tongues destined for human consumption (as described as

‘ox tongue’). Even in the tongues in which no visible tonsillar tissue remained,

histological examination revealed lymphoid tissue in more than 90 per cent.

Variations in the distribution of the lingual tonsil suggested that even after the

most rigorous trimming of the root of the tongue, traces of tonsillar tissue may

remain. There is a risk that ox tongue on sale in the UK may contain infective

material from pre-clinical BSE-infected cattle.

NB A statement based on research similar to that reported in this paper was issued

by the Food Standards Agency in June 2003 and discussed by SEAC that month.

SEAC reviews risks from recent blood transfusions

A meeting of the UK expert committee SEAC considered whether donated organs,

such as bone marrow, would be infected if CJD-contaminated blood had been

administered only hours before the donated organ was removed.20 It concluded

that In the absence of robust and direct data it could be assumed that the vCJD

agent is widely distributed within the body in the first 24-48 hours following a

blood transfusion but may not necessarily have sufficient time to replicate to a

significant extent. Thus, the infectivity level in a particular tissue/organ shortly

after transfusion of infected blood may be dependent predominantly on some or all

of the following factors:

7

• type of tissue/organ

• possible clearance of infectivity

• possible infiltration and retention of the vCJD agent in the tissue/organ

• blood content of the tissue/organ

• infectious dose in the transfused blood

SEAC noted that relevant data on prion replication and spread following transfusion

were extremely limited and mostly from animal models not directly applicable to

the human situation. However, in the first few days following a transfusion with

infected blood, significant prion replication was unlikely and, therefore, tissue

prion levels would be related to the blood supply to the tissue in question. Highly

vascularised organs such as liver, lung and spleen were more likely to contain the

agent compared with other organs.

The committee agreed that a balance must be struck between the small increased

risk of prion transmission by transplant and the benefit to potential organ

recipients of receiving a transplant, especially where tissues/organs are scarce.

The committee noted that screening of cadaveric donors for the presence of

abnormal prions prior to transplantation, washing tissues/organs to remove blood

before their use, and avoiding the pooling of tissues may reduce transplant

associated transmission risks.

Estimated infectivity levels per unit whole blood

Blood fraction

Infectivity intravenous

ID50/450mL contaminated whole

blood unit

Whole blood 900

of which

Plasma

480

Buffy coat 201

Red blood cells 219

Red blood cells (leucodepleted) 2

No difference of risk between vertebra from 12-month and 30-month cattle

The UK expert committee SEAC has stated that the difference in the BSE-related

risk to the UK population from vertebral column derived from cattle aged either 12

or 30 months of age was negligible.21

The UK Food Standards Agency had asked SEAC to review an assessment of the

possible UK exposure to BSE associated with vertebral column from cattle aged

under 12 or under 30 months. The committee noted that some uncertainties

remained with regard to the extent of the species barrier between cattle and

humans although these uncertainties do not significantly affect the overall

conclusions. Exposures had been calculated for the UK population, without

considering whether a small subgroup within the population might consume most of

the UK beef on the bone. Nevertheless, although exposure would be higher in

consumers of beef on the bone than for the general population assumed in the

study, it was considered that the increased risk to this population group would still

be very small, and that the difference between the two age cut-offs for the

specified risk material was insignificant.

8

HPA suggests epidemic passing

The CJD quarterly review of the UK Health Protection Agency has suggested that

the peak number of vCJD cases has passed.22 A graph of the dates of onset of

disease show a peak at about 6 deaths per quarter in mid 2000 and has since

declined to a current incidence of about 1.5 deaths per quarter. Extrapolating the

best fitting model (the quadratic model) gives an estimate of 5 deaths in the next

12 months (95% prediction interval 1 to 11). The report warns that although a peak

has been passed, it is possible that there will be future peaks, possibly in other

genetic groups. There is also the possibility of ongoing person to person spread.

9

General news

Canadian farmers claim damages for BSE

Canadian cattle farmers have launched a C$7 billion (£2.9 billion) class action

lawsuit against the Canadian government and an Australian-based feed maker for

failing to prevent BSE in Canadian cattle.23

The lawsuit has been filed on behalf of more than 100,000 farmers from the

provinces of Ontario, Quebec, Alberta and Saskatchewan, and claims that in the

mid-1990s Ottawa lost track of 80 of 190 cows imported from Britain that it was

supposed to be monitoring for BSE. The lost British cows were recycled into cattle

feed and fed to other Canadian cattle, the lawsuit claims. Australian-based Ridley

Corporation, through its Canadian subsidiary Ridley Inc which allegedly made the

feed, should have known that it could have been contaminated by BSE, the lawsuit

claims. ‘In 1996 they voluntarily stopped using cattle remains in cattle feed in

Australia, and the Australian cattle industry remains BSE-free. But they didn't stop

using it here,’ said Cameron Pallett, one of the lawyers representing the farmers.

The Canadian government did not impose a ban on feeding cattle remains to cattle

until August 1997.

US farmers join USDA to re-open Canadian border

The largest farm organization in the US – the American Farm Bureau – has joined

the US Department of Agriculture's appeal of a court decision that is keeping the

border closed to Canadian cattle.24 Nearly 30 other local farming bodies have

joined the Bureau in support of the reopening of the border.25 In March, US District

Judge Richard Cebull granted the Ranchers-Cattlemen Action Legal Fund (R-CALF) a

temporary injunction to keep cattle out, just days before the USDA had planned to

allow shipments to begin again. "There are many, many producers in the United

States who do not agree with R-CALF, but their silence was a form of consent,"

said an AFB spokeswoman.

No date has been set for the appeal court to hear the case. In July, Judge Cebull

will hear arguments to determine whether the border reopens, remains closed or

expands the temporary injunction to other Canadian beef products. The Alberta

Beef Producers and Canadian Cattlemen's Association have applied for intervener

status in the case. An earlier bid by the Canadian government to submit an amicus

brief was denied.

US continues to press Japan to lift import ban

US trade representatives are continuing to put diplomatic pressure on Japanese

authorities to lift Japan’s current ban on US beef imports.26 Rob Portman, US Trade

Representative nominee, said that pressing Japan to quickly lift its 16-month-old

import ban is his "top priority." Meanwhile Japanese meat hygiene authorities are

investigating two suspected cases of BSE in cattle tested during April.27 Tissue

samples were sent to the National Institute of Infectious Disease in Tokyo for more

screening. They would mark Japan's 18th and 19th cases of BSE, if confirmed.

US to put pressure on OIE to change standards

The USA is expected to press for changes to the standards for beef trading at the

World Animal Health Organization (OIE) during May.28 A set of standards was agreed

10

between the US, Canada and Mexico in March, and set nine conditions, including a

requirement that exported beef must be from carcasses that have had the SRM

removed at slaughter and a ban on imports of animals from herds with known cases

of BSE.

If the standards are adopted by the OIE, individual countries that attempt to

maintain bans on imports from countries that comply with the standards may face

legal challenge under World Trade Organization rules that prohibit unfair trading

barriers. This might bypass the current negotiations between the US and Japan,

forcing Japan to accept all US beef exports without any age or testing restrictions.

The exact standards have not been published, but are reported to be based on the

following guidelines: a definition of specified risk material and rules for removing

it; a prohibition on exports of meat from non-ambulatory, disabled cattle; a

prohibition on the use of pithing and air-injection stunning; a prohibition on the

mechanical harvesting of meat from the skull and vertebral column of cattle over

30 months of age; import controls; surveillance guidelines; ruminant feed

restrictions; improved cattle identification systems; and a four-part determination

of risk status based on release, exposure, consequence and risk estimation.29

Meanwhile, the OIE is reported to be calling for strict curbs on beef trading of

material at high risk of containing BSE contamination, such as brains, but has

proposed easing trade restrictions on muscle separated from the bone, saying it is

safe from BSE.30 The OIE is also reported to be circulating proposals to member

governments to amend the BSE controls by changing the definition of bovine

intestines under SRM guidelines.31 Japanese government officials said that the OIE

is requesting that only certain parts of the intestine need to be designated as SRM,

instead of the entire intestine. Details are not available from the OIE website.

US welfare group opposes move to relax ‘downer’ rules

Farm Sanctuary, a leading US farm animal protection organization, has condemned

the Bush Administration's proposal to weaken the current ban on the slaughter of

injured or ‘downer’ cattle for human consumption.32 In response to the first case of

BSE in the USA in 2003, the USDA imposed a ban on the slaughter of all downer

cattle for human consumption, but the new Bush proposal will allow certain cattle -

- those with broken limbs and those which are under 30 months old – to enter the

food chain. ‘This is misguided,’ said Farm Sanctuary president Gene Bauston,

‘because it ignores the fact that there are many disease-driven reasons that a cow

may fall and break her limbs – including affliction with bovine spongiform

encephalopathy.’

As part of a 2004 lawsuit settlement with Farm Sanctuary, the USDA acknowledged

that ‘studies from Europe appear to show that non-ambulatory cattle, or "downed"

cattle, have a greater incidence of BSE than other cattle, and, moreover, that the

clinical signs of BSE cannot always be observed in cattle.’ In 2004, when the USDA

requested public comments on the issue of downed cattle slaughter, the agency

received 22,000 comments. Of these, ninety-nine percent supported an all-out ban

on letting downer cattle into the food supply.

The USDA’s new proposals were also condemned by consumer groups.33 Caroline

Smith DeWaal, food safety director for the Center for Science in the Public

Interest, said ‘Downer cattle represent less-healthy animals and should be kept out

of the food supply.’

11

USDA accused of faulty testing

The US Agriculture Department has denied allegations from two former employees

that faulty animal testing procedures may have kept officials from finding more

cases of BSE in the United States.34 Former USDA veterinarians Lester Friedlander

and Masuo Doi were quoted separately by Canadian news outlets saying that the

United States may have more cases of BSE. Friedlander, who retired in 1995 as a

food safety inspector in Pennsylvania, alleged that the USDA knew about the

additional cases and was hiding the information. Agriculture Secretary Mike

Johanns told reporters the USDA would not investigate Friedlander's allegation

because he provided no proof.

Dr. Masuo Doi, the USDA veterinarian in charge of investigating one of the 1997

cases, says he fears the right tests were not done and his own department did not

properly investigate whether the cows had BSE.35 In one case, analysts did not test

the part of the cow's brain most likely to show signs of BSE. In a second case, Doi

was unable to obtain documentary evidence the animal was clear of BSE.

Canadians urged not to adopt US meat inspection system

Canada risks losing its independent testing and inspection capacity needed to

protect the health and safety of Canadians if a proposed Food Inspection Agency

Act is passed, according to Canadian and US experts who addressed the

parliament’s House Standing Committee on Agriculture.36 Dr. Lester Friedlander,

former USDA veterinarian and meat inspector, said ‘Rules and regulations are

broken every day in the United States because the government is not enforcing

them, allowing, for example, animal protein to be fed back to cattle.’ He has seen

this occur in the US and believed it is a growing problem in Canada. He said ‘The

public must insist that the food safety regulatory function be separated from the

governmental agency promoting corporate agribusiness. We need a genuine,

separate department of consumer protection.’

According to a civil advocacy group, the Council of Canadians, the proposed Act

would allow the Canadian Food Inspection Agency to accept testing and

certification results from other countries and is designed to harmonise with US

regulations. However, the US system currently permits irradiation of meat, which is

not allowed in Canada, has failed to meet World Health Organization guidelines for

preventing BSE, and relies on voluntary compliance when companies are found in

violation of its regulations. Furthermore, US whistle-blowing scientists who act in

the public interest are not protected.

‘This government’s "Smart Regulation" legislative renewal project, which

includes Bill C-27, is what I describe as the "Corporatization of Knowledge"—

instituting private interests ahead of the public good,’ says Dr. Shiv Chopra, who

along with colleagues Dr. Margaret Haydon and Dr. Gerard Lambert, blew the

whistle on conflicts of interests in Health Canada’s drug approval process. ‘We will

request the postponement of the entire legislative renewal process until after a full

public inquiry into what we, as scientists, have been suffering on account of the

pressure exerted on us to pass drugs and other products and methods of

questionable safety.’

For more on the Council of Canadians, see http://www.canadians.org/ .

12

USDA approves Canadian BSE measures

The US Department of Agriculture’s Animal and Plant Health Inspection Service

(APHIS) have released a review of Canada’s BSE cases and control measures.37 The

team found that Canada’s epidemiological efforts ‘were not only appropriate but

exceeded levels recommended by an international team of BSE experts,’ said John

Clifford, APHIS deputy administrator for veterinary services. The team reviewed

Canada’s epidemiological investigations following four confirmed cases in Alberta

and evaluated the possibility of a common source of exposure; the likelihood that

other high-risk animals from Canada are currently present in the United States; and

animal feed issues that may have led to exposure to US cattle.

The team’s report concluded that the geographic and temporal proximity of the

Canadian BSE cases suggests that they may have a common exposure point. The

report also strongly suggests localized exposure through feed manufactured prior to

the feed ban, or soon after its implementation. The team also noted that the

Northwest region of the United States could be considered within a broadly defined

movement area that could be at higher risk of exposure to BSE.

BSE has cost US beef trade up to $5bn

The Kansas Department of Agriculture has estimated that the US beef industry has

lost between $3.2bn and $4.7bn in export revenues as a result of the BSE crisis.38

The report, prepared jointly with Kansas State University and entitled ‘The

Economic Impact of BSE on the US Beef Industry’, notes that within days of the

announcement that a cow in Washington state had been diagnosed with BSE in

December 2003, 53 countries banned imports of US cattle and beef. In 2003, US

beef exports were valued at $3.95 billion and accounted for 9.6 percent of US

commercial beef production. Five countries – Japan, Mexico, South Korea, Canada

and Hong Kong – received 90 percent of US beef exports in 2003. Mexico and

Canada partially resumed beef imports in 2004, but overall the quantity of US

exports fell by 82 percent below 2003 levels.

The report evaluates the potential impact BSE testing could have if it were used to

regain export markets. Researchers estimate that it would have cost about $640

million to test all cattle slaughtered in the United States in 2004, but that figure

does not include any investment needed to place testing facilities in a beef

processing plant.

Regulations issued in 2004 by USDA's Food Safety and Inspection Service had an

estimated net cost to the beef industry of approximately $200 million, plus some

one-time investments that were substantial, but varied widely from firm to firm.

Those costs related to the inability to market non-ambulatory cattle, the need to

age cattle presented for slaughter, to segregate and process separately cattle older

than 30 months and to prevent certain tissues from entering the food supply.

The study also examined potential costs related to feed regulations being

considered by the Food and Drug Administration. Last July, FDA published an

advance notice of proposed rulemaking seeking input on regulation changes the

agency was considering to ban from cattle feed all bovine blood products, plate

waste and poultry litter, and to require dedicated equipment for producing

ruminant and non-ruminant feed to prevent cross-contamination. To date, FDA has

not made the rules final.

The report is available online at

http://www.agmanager.info/livestock/marketing/bulletins_2/industry/default.asp

13

Germany finds BSE in animal born 2001

German veterinary authorities have reported a case of BSE in an animal born in May

2001, German news agencies have reported.39 Meat and bone meal was prohibited

in cattle feed the previous year.

New York authorities find CWD in wild deer

A systematic hunt to determine whether CWD has spread from two Oneida County

deer farms has been launched in New York state with the erection of a field

laboratory and the start of a sampling regime that will collect more than 400 wild

deer in a ten mile radius of the farms.40 By the end of April one wild white-tail

deer had been identified as a possible positive case.41 New regulations will require

hunters who kill deer in Oneida County and parts of Madison County to be passed by

state checkpoints.42 Samples will be taken for testing from deer killed by hunters

and from deer involved in motor vehicle accidents.

In March, a 6-year-old white-tailed doe from an Oneida County farm tested positive

for the disease, becoming the first known case east of Illinois. Four other captive

deer on another nearby farm have since tested positive. One of the first NY deer to

test positive had been served at a meeting of 350 people at a reunion dinner. Texas

CWD expert Professor Tam Garland said that there was no evidence that CWD could

spread to humans, but that the dinner had provided an opportunity to do an

epidemiological study.43 A state health department spokesman said that although

no medical studies are planned, the Oneida County health department has a list of

those who ate the infected deer. The people can be quickly contacted if the need

arises.

North Carolina proposes ban on deer as pets

The North Carolina Wildlife Resources Commission (NCWRC) has said that the

majority of households that keep elk, white-tailed and mule deer, do so for ‘family

companionship’ and that a ban on new licenses for captive deer may help to thwart

the spread of CWD.44

Kelly Douglass, captive cervid program leader for the NCWRC, said that although

there was no documented case of CWD in North Carolina yet, the Commission was

to hold a public hearing in May on prohibiting future captivity licenses in an

attempt to prevent the disease from spreading to the State. During the five-year

incubation of the disease ‘the animals show no signs of illness but are contagious

and can infect other animals,’ she said.

A court in Tennessee has upheld the state’s right to ban the keeping of deer.45 The

law had been introduced in Tennessee in 1991 as a disease control measure, but

has been challenged by traders and hunters three times since then.

DEFRA changes Scrapie Flocks Scheme

Amendments to the controls on scrapie-affected farms under the Compulsory

Scrapie Flocks Scheme have been announced by the UK Department for the

Environment, Food and Rural Affairs (DEFRA).46 The scheme, which applies control

measures to farms where a case of scrapie is confirmed, has been amended

following changes to EU legislation. The amendments are:

14

• An extension from three to five years of the period in which derogations to

delay culling can apply for breeds or flocks with low levels of resistant alleles or

at risk of inbreeding;

• Lambs of specified genotypes will be allowed to be moved from scrapieaffected

flocks for fattening for slaughter;

• Controls can now be applied to the individual flock on a farm based on a

veterinary assessment;

• Official movement restrictions can now be placed on sheep and goats on farms

when a case of scrapie is suspected rather than when it is confirmed;

As of March 18, there were 113 flocks (involving 64 holdings) in the scheme, which

is operated under the National Scrapie Plan for Great Britain. DEFRA said it would

continue to keep the operation of the scheme under review and would press for

other amendments to EU legislation when this was necessary.

84 countries maintain ban on British beef

Eighty-four countries, including the United States, India and Australia, still have a

ban on the import of British beef, after the BSE crisis. A spokesperson for the

Department for the Environment, Food and Rural Affairs said the reasons cited for

the bans were ‘animal and public-health related’.47 Meanwhile the European

Commission has so far not moved to downgrade the UK’s risk rating from ‘high’ to

‘moderate’ despite a statement from the European Food Safety Authority’s expert

Panel on Biological Hazards that the UK now conforms to the definition of

‘moderate’ risk under the OIE’s definitions, announced in March.48 The OIE

threshold for a country to be considered moderate risk in terms of BSE is set at 200

BSE positives over a 12 months period per 1 million adult cattle (aged over 24

months).

Irish oxtongues broke SRM rules

The UK Meat Hygiene Service (MHS) has reported finding six consignments of fresh

beef tongues, 192 tongues in total, exported to the UK from the Republic of

Ireland, which have not been harvested in accordance with the TSE Regulations

that require tongues be removed in such a way as to minimise the risk of lingual

tonsil (which is SRM) remaining attached to the tongue. The breaches were

discovered on the 23 and 24 February and the 1 and 8 of March 2005.49

Illegal slaughterer jailed for six months

A farmer caught operating an illegal slaughterhouse at his remote small-holding in

the north-east of Scotland was jailed for six months this spring,. The operation is

believed to be part of a highly-organised criminal network that poses a risk to

public health.50

Julian Jones, 41, was jailed for six months at Elgin Sheriff Court after he was

arrested for his part in an illegal operation to supply outlawed sheep smokies – a

Caribbean and West African delicacy – to ethnic communities throughout England.

Arresting officers found the carcasses of 62 sheep that had been slaughtered by

having their throats slit and left to bleed to death in a filthy, faeces-strewn barn.

Most of the animals had not been stunned before having their throats slit. Some of

the carcasses contained parts of the spinal cord and spleen, material that should

be removed as part of the control measures to prevent the risk of BSE infection.

15

Netherlands reports first vCJD case, France adds 2 more

The Dutch government has reported the country’s first case of vCJD in April, but

stated that Dutch beef is safe to eat due to the safety control measures introduced

over the last decade.51 The patient was reported to be a 26-year-old woman from

Utrecht and has been neither a donor nor recipient of blood or tissue. She has

never lived outside of the country, and the presumed source of her infection is

contaminated beef.52

There have been more than 70 BSE cases in animals in the Netherlands since 1997,

but the government said that ‘all susceptible cattle are now tested for BSE at

slaughter’. The Netherlands is one of the world's biggest exporters of meat and

dairy products and its livestock sector has undergone major intensification in the

past few years with most animals raised on specialised farms.

Meanwhile, French authorities are reported to have announced two more cases of

vCJD, bringing the total to four over the last half-year, and 11 cases in total for the

country.53 The two individuals diagnosed with vCJD ‘are not on the records as

having been blood donors,’ the Institute of Health Surveillance (InVS) said in a

statement.

Japanese fear blood shortages

The Japanese Ministry of Health has said that the country’s medical facilities are

facing an unprecedented blood shortage and may start running out in some areas.54

The Health, Labor and Welfare Minister, Hidehisa Otsuji, was filmed on the streets

of Tokyo urging ‘teenagers and those in their 20s’ to donate blood.

According to the Japanese Red Cross Society, blood supplies are normally lower in

March and April each year because student donors are away for spring break and

office workers are busy closing their books for the fiscal year at the end of March.

The amount of overall blood available has also dropped in recent years due to the

declining birth rate.

However, the government's recent proposal to tighten controls on donations from

people who have travelled to Britain may also be having an effect. At one point the

stock of red blood cells -- a gauge of blood supply -- stood at 74 percent of normal,

defined as the level sufficient for meeting demand for a period of three days, the

Red Cross said. Supply in the Tokyo area dropped to 64 percent. Anything below 70

percent indicates supplies may run out during major disasters or other high-demand

crises.

Last month, the ministry concluded that the first Japanese patient to die from the

vCJD had probably been exposed during a stay in Britain or France during the

1990s. People who stayed in Britain or France for at least six months since 1980

have already been banned from giving blood, according to the Red Cross. The ban

was tightened last February to cover those who were in Britain for at least one

month. The restrictions on people who travelled to France have remained

unchanged. Plans to tighten the rules to exclude anyone who visited Britain for as

little as a day were due to take effect in May but may be delayed while blood stock

levels recover.

Confusion over fate of NIH brain samples

A US health official who had previously said that a collection of human brain tissues

might be destroyed has subsequently been reported as saying the samples will be

16

preserved.55 The collection of frozen samples held by the National Institutes of

Health (NIH) contains brains and other tissues from hundreds of people who died

from CJD. The NIH official, Eugene Major, acting director of the basic neuroscience

program, told United Press International (UPI) in March the collection would be

destroyed. The remaining collection ‘has very little remaining value’ and could be

destroyed if another entity does not claim them, he said.

Subsequently Florence Kranitz, the president of the CJD Foundation, a non-profit

patients' advocacy group, said that Major had told her that the remaining tissues in

the collection would be preserved. UPI reports that Major has not responded to emails

or a phone call from UPI seeking clarification of his alleged remarks.

Public-private co-funding for UK’s vCJD treatment research

GlaxoSmithKline Plc, Europe's biggest pharmaceutical company has joined with the

UK Medical Research Council and the UK Department of Health to co-fund a

research programme to search for treatments for vCJD.56 The company will provide

its library of drug compounds, allowing the research team to screen the molecules

for their potential activity against the infectious proteins that cause TSEs in

humans and animals.

‘Many person-years of very difficult work at the MRC have been invested to get to

the stage where development of a drug to completely block prions appears

realistic,’ Dr John Collinge, director of the MRC Prion Unit and head of the

Department of Neurodegenerative Disease at University College London, said. The

first phase of the work to find a possible treatment may take six years, the MRC

said.

‘Last’ of the dura mater CJD cases

A coroner’s court has been told that a case of CJD caused by the use of

contaminated dura mater could be the last to occur in the UK.57 The dura mater – a

membrane surrounding the brain obtained from a donor corpse – had been stored

with other samples, one of which may have been contaminated. It was determined

to be the cause of death of Mr Simon Stratford, a father-of-four from St Neots in

Cambridgeshire, in 2003.

Mr Stratford, 34, had the repair patch inserted into his head after surgeons

removed a tumour on his skull in 1987. The material, known as a Lyodura patch,

was withdrawn from sale by the manufacturers, West German company B Braun,

over a decade ago, after 900,000 patches had been produced world-wide during a

28-year period.

Professor Robert Will, consultant neurologist at the Western General Hospital in

Edinburgh, told the inquest that 168 patients had contracted CJD after having some

kind of graft onto the membrane surrounding their brains, seven of which were in

the UK. He said CJD contracted during this form of surgery emerged, on average,

nine years later, with the longest incubation period being 22 years. He said ‘We

think that the majority of cases have emerged by now. There is no reason to think

there is going to be great numbers of cases emerging in the future. Mr Stratford

may well be the last victim in the UK.’

After the hearing in Huntingdon, Mr Stratford's widow Colleen, 37, said she was

considering legal action. A verdict of misadventure was recorded by the coroner.

17

Blood transfusions may prevent organ donation

Transplant services may restrict the surgical use of tissues from patients who have

undergone blood transfusions to protect recipients from the small risk of vCJD.58

The availability of bone, skin, tendons, ligaments, corneas and heart valves could

be hit, although some other organs, and bone marrow, may not be included as

supplies are already insufficient.

Anyone who has had blood transfusions since 1980 is already banned from donating

blood following strong evidence that two people have been accidentally infected

through transfusions. This has led to a fall of 5-10% in potential donors. Now safety

advisers and tissue banks want to balance the risks and benefits on tissue donation,

although no decisions are likely until the autumn.

Health officials want to establish how many transplant donors have had blood

donations either years before or in the week leading up to their deaths. Many are

likely to have done so, since they are often victims of road or other accidents or

haemorrhages, who will have received highly intensive care. The expert advisory

committee, SEAC, has suggested that for most organs the risk of transmitting vCJD

may be less if the donor only received a transfusion in the preceding days – which

may mean organ supplies might not be hit as seriously as if all donors who had

received transfusions were barred from donation.

People needing new hearts, lungs, kidneys or livers are often so ill that the benefit

of a transplant would far outweigh even the slight risk of infection by the CJD

family of diseases.

More than 6,000 people are awaiting organ transplants, yet last year 1,244 donors,

most of them dead, supplied fewer than 2,850 organs.

[See ‘Science’ section above for further details of SEAC’s view on transfusions prior

to organ donation.]

18

Official figures

BSE

The figures below are derived from the OIE59, national authorities and news

sources60. The figures include cases from farmers’ and vets’ reports (passive

surveillance) and cases discovered during testing of at-risk animals, fallen stock or

animals entering the food chain (active surveillance).

Reported cases of BSE

Includes passive and active surveillance cases

country total BSE cases

since 1986

total in 2005

reported by

1 May 2005

Great Britain 180 776 69

Isle of Man 437 0

Guernsey 700 0

Alderney 2 0

Jersey 150 0

Northern Ireland 2 139 7

GB and NI total 182 915 76

Azores 5 0

Austria 1 0

Belgium 130 1

Canada 4 1

Czech Republic 18 3

Denmark 14 0

Falkland Islands 1 0

Finland 1 0

France 960 14

Germany 378 15

Greece 1 0

Ireland 1507 24

Israel 1 0

Italy 129 3

Japan 19 5

Liechtenstein 2 0

Luxembourg 2 0

Netherlands 77 0

Oman 2 0

Poland 31 11

Portugal 965 13

Slovakia 19 0

Slovenia 5 0

Spain 542 27

Switzerland 457 1

United States 1 0

NB Reported cases from active surveillance are based on sampling criteria which

differ between member states, with some states testing additional categories to

those required under EU law.

BSE testing of healthy cattle

The testing of healthy adult cattle aged over 30 months entering the food chain or

for surveillance purposes is required under EU regulations. However, country-tocountry

comparisons need to be treated cautiously. Some countries test some

categories of animals from age 24 months. The sample sizes vary greatly, with

higher margins of error for the smaller samples.

The ages at which animals are typically sent for slaughter will also affect the

likelihood of finding disease. Most older cattle are dairy cows past their peak milk

yields. In larger herds the cattle may be sent for slaughter shortly after their yields

start to fall, whereas in smaller herds the cattle may be kept longer as the

replacement cost represents a relatively large amount of capital expenditure.

Thus, in countries that generally have small herd sizes, the cattle may be kept for

longer on the farm and the chances of BSE cases developing will be higher.

Tests on healthy cattle subject to normal slaughter61

Jan-Dec 2003 Jan-Dec

2004

Country Tests on

healthy

cattle

Positive

cases

Cases per

million

tests

Tests on

healthy

cattle

Positive

cases

Cases per

million

tests

Austria 205 659 0 0 188 538 0 0

Belgium 356 184 10 28 356 813 6 17

Denmark 250 359 1 4 244 902 0 0

Finland 108 207 0 0 107 614 0 0

France 2 920 157 37 13 2 624 634 17 6

Germany 2 337 605 23 10 2 251 062 34 15

Greece 24 533 0 0 26 161 0 0

Ireland 600 586 31 52 605 386 20 33

Italy 648 894 15 23 851 014 2 2

Luxembourg 14 598 0 0 13 575 0 0

Netherlands 439 403 11 25 467 448 5 0

Portugal 81 633 44 543 78 783 21 267

Spain 453 772 75 166 468 984 37 79

Sweden 9 856 0 0 10 318 0 0

UK 242 827 19 79 341 708 10 29

Total EU-15 8 694 273 266 31 8 636 940 152 18

Cyprus 6 401 0 0 5 888 0 0

Czech

Repub

133 046 3 23 130 124 2 15

Estonia 21 277 0 0

Hungary 7 102 0 0 80 528 0 0

Latvia 4 838 0 0 28 017 0 0

Lithuania 7 418 0 0 47 506 0 0

Malta 1 089 0 0 2 067 0 0

Poland 428 452 4 9 446 770 8 18

Slovakia 65 192 1 15 63 553 5 79

Slovenia 54 751 0 0 35 767 0 0

Total EU-25 9 402 562 274 29 9 498 437 167 18

Norway 9 804 0 0 10 437 0 0

Bulgaria 7 789 0 0

20

BSE testing of sick animals

The testing of cattle fallen ill at the farm or in transit, or those presenting as ill at

the abattoir, aged over 24 months, is required under EU regulations.

Positive test results on suspect, at-risk and cohort cattle62

Jan-Dec 2003 Jan-Dec

2004

Country Cohort

animalsa

Cattle at

riskb

Suspected

casesc

Cohort

animalsa

Cattle at

riskb

Suspected

casesc

UK 0 404 184 0 234 91

Total EU 15 9 777 306 5 493 174

Total

accession

0 0 1 0 12 0

Norway 0 0 0

Bulgaria 0 0 0

a = Animals born or reared with BSE cases, offspring of BSE cases, animals from

herds with BSE.

b = Dead-on-farm, emergency slaughtered, sick at ante-mortem inspection.

c = Animals reported as BSE clinical suspects ( = passive surveillance).

BSE in Britain

GB: Confirmed BSE cases63

year BSE suspected cases new herds

to end 1987 675 333

1988 2 184 1 918

1989 7 137 3 391

1990 14 181 4 478

1991 25 032 5 817

1992 36 682 7 266

1993 34 370 5 790

1994 23 945 2 654

1995 14 302 1 401

1996 8 016 764

1997 4 313 483

1998 3 180 399

1999 passive reports: 2 258

active testing: 18

248

2000 passive reports: 1 311

active testing: 44

169

2001 passive reports: 781

active testing: 332

124

2002 passive reports: 445

active testing: 594

93

2003 passive reports: 173

active testing: 374

46

2004 passive reports: 82

active testing: 226

12

2005 to mid-April passive reports: 10

active testing: 59

0

Total reported passive 179 129

active 1 647

35 403

21

The incidence of BSE is falling, but against this decline in the number of cases must

be set the possibility that cattle carrying BSE have been slaughtered before

showing the disease, under the following schemes:

• the Selective Culling scheme which, from early 1997 to mid-2002,

removed over 77,300 UK cattle at greatest risk of developing BSE based on

their herd and feeding histories.64

• the Over Thirty Month slaughter scheme which, from April 1996 to June

2004, has removed over 7.3 million older cattle from the national herd, a

rate of about 8% of cattle each year (19% of adult animals),65 in addition

to an unspecified number of older cattle culled under the foot and mouth

disease culling regime.

• the BSE Offspring Cull, which since October 1998 has identified over

32,600 offspring of BSE cases that have been, or will be, slaughtered.

Currently 50 of the animals are awaiting slaughter and 158 are deemed

untraceable.

Infection rates

Figures for Great Britain show:

• Proportion of cattle herds affected with BSE: 38.5%

of which

• Proportion of dairy herds affected: 62.0%

• Proportion of beef suckler herds affected: 17.5%

Annual incidence among cattle aged over 24 months:

• Great Britain: 53.3 cases per million (Mar 04 - Feb 05)

• Northern Ireland: 31.5 cases per million (Mar 04 - Feb 05)

Since the emergence of the BSE epidemic in 1986, the large majority of animals

diagnosed with BSE have not shown the disease until they were aged over 30

months old. However, cases of clinical BSE were found in animals aged 30 months

or younger every year from 1986 through to 1996.

• Youngest confirmed case aged 20 months

• Second youngest case aged 21 months

• Eleven cases reported aged under 25 months

Since the year 2000, the youngest case has been an animal born in October 2001

and aged 39 months at slaughter (see next section).

BSE cases born after the 1996 feed ban

The majority of UK BSE cases now being reported were born after the 1988

ruminant protein ban, which had been introduced to prevent the further spread of

the disease. The clear failure of those regulations led to more stringent measures,

applied in mid-1996, in which all mammalian meat and bone meal was banned from

ruminant feeds (subject to some loopholes). However, since that later date several

animals have been born that subsequently developed BSE. These animals are

sometimes referred to as BARB cases, i.e. cases Born After the Reinforced Ban.

In the UK, 115 cases of BSE have been detected in BARB animals, 100 cases in Great

Britain and 15 in Northern Ireland.66 This includes the first case of a BARB animal

born in 2001.

22

BARB cases, GB and NI

cases confirmed by 1 May 2005

date of birth confirmed cases,

passive reported

confirmed cases,

active surveillance

Aug-Dec 1996 5 15

1997 13 32

1998 8 22

1999 3 13

2000 1 2

2001 0 1

Total after

01/08/96

30 85

Whether these cases have been the result of insufficient enforcement of the feed

ban, or because maternal transmission has perpetuated the disease or because

there are other agents that have not been fully controlled controlled, has not been

determined. A review of the BARB cases up to early November 2003 found no

evidence for maternal transmission and no evidence that BARB cases were

transmitted environmentally e.g. in high-incidence herds or from abattoir waste.67

Questions remain about other factors, such as the use of artificial colostrum and

the content of weaning feeds, and the continued potential contamination of feed

in mainland Europe before strict controls were introduced in 2001.

TSEs in sheep and goats

Testing of sheep and goats for TSEs is required under EU regulations. Results of the

testing programme of animals at risk (fallen stock, suspected cases etc) and

healthy animals are reported below:

Tests on sheep and goats at risk

EU15, January-December 200368

Number of

tests of sheep

Positive cases Number of

tests of goats

Positive

cases

Eradication – cohorts

and offspring of cases

30 950 872 4 495 12

Sick and fallen

animals

106 061 115 21 004 6

TSE clinical suspects 1 214 517 92 11

EU 15 total at-risk 138 324 1 504 25 591 29

EU25, January-June 200469

Number of tests

of sheep

Positive

cases

Number of tests

of goats

Positive

cases

Eradication – cohorts

and offspring of cases

13 331 472 1 196 24

Sick and fallen

animals

86 758 111 9 720 7

TSE clinical suspects 383 196 115 15

EU 25 total at-risk 100 472 779 11 031 46

Norway 2 929 6 76 0

23

Tests on healthy sheep and goats

January-December 200370

Number of tests

of healthy

sheep

Positive

cases

Number of tests

of healthy goats

Positive

cases

UK 72 518 46 193 1

EU 15 total 341 241 236 35 947 16

Norway 33 520 5 1 610 0

Slovakia 3 924 1 4 0

January-June 200471

Number of tests

of healthy

sheep

Positive

cases

Number of tests

of healthy goats

Positive

cases

UK 2 975 2 12 0

EU 25 total 65 748 45 6 074 1

Norway 4 423 3 20 0

Scrapie in Britain

Data on scrapie in sheep and goats have been collected since the disease became

notifiable in 1993.72 Not all cases were confirmed until compulsory slaughter

legislation was introduced in 1998. Interpretation of trends before 1998 may

therefore be unreliable.

Scrapie cases (Great Britain)

confirmed pending or inconclusive

1993 328 3

1994 235 2

1995 254 1

1996 460 3

1997 508 4

1998 499 1

1999 598 2

2000 568 0

2001 295 9

2002 427 1

2003 439 10

2004 333 9

2005 to 31

January

21 12

Active surveillance for scrapie undertaken in Britain since 2001 has found 133 cases

in sheep out of more than 129 000 tested, and one case among more than 600 goats

tested.

24

CJD

One hundred and fifty-five cases of vCJD had been reported in the UK by early April

2005 including five probable cases currently alive.

Outside of the UK, there have been eleven cases in France (one of which was

probably due to the ingestion of bovine pituitary extract as a sports dietary

supplement), two cases in the Republic of Ireland (one with a history of UK

residency), one case in the USA (with a history of UK residency), one case in

Canada (with a history of UK residency), one case in Italy (no history of UK

residency) and one case in Saudi Arabia (possible history of UK residency).73 A case

in Hong Kong has been included in the UK numbers because of a history of long

term UK residency.74 A case in Japan was confirmed as vCJD in February 2005.75 A

suspected case of vCJD is being investigated in Morocco.76 A suspected case is

being investigated in the Netherlands.77

UK suspected CJD (referrals)78

CJD referrals

1996 134

1997 161

1998 154

1999 170

2000 178

2001 179

2002 163

2003 162

2004 112

2005 to 29 April 31

UK CJD deaths79

Probable and

confirmed vCJD

Sporadic CJD Other CJDs

1990 -- 28 5

1991 -- 32 4

1992 -- 45 8

1993 -- 37 9

1994 -- 53 8

1995 3 35 9

1996 10 40 10

1997 10 60 11

1998 18 63 8

1999 15 62 8

2000 28 50 4

2001 20 58 9

2002 17 72 5

2003 18 77 11

2004 9 49 6

2005 to 29 April 2 10 1

Total since

1990

150 771 116

UK: Suspected vCJD cases alive: 5

25

Abbreviations

BAB = Born After the Ban -- cattle which born after the ban on the inclusion of

mammalian meat and bone meal (MMBM) in cattle feed introduced in 1988. This

ban has subsequently been shown to be inadequate at preventing the use of MMBM

in feed.

BARB = Born After the Real Ban – cattle born after the more stringent ban on the

use of mammalian mat and bone meal, introduced in August 1996.

BSE = Bovine Spongiform Encephalopathy, a disease of cattle first recognised circa

1986.

CJD = Creutzfeldt Jakob Disease, a human form of spongiform encephalopathy.

CWD = Chronic Wasting Disease, a TSE found in elk and deer in mid-west USA.

DEFRA = UK Department for the Environment, Food and Rural Affairs (absorbed

MAFF).

DoH = UK Department of Health.

EC = European Commission, the executive arm of European governance.

FSA = UK Food Standards Agency.

MAFF = UK Ministry of Agriculture, Fisheries and Food (incorporated into DEFRA in

2001).

MBM = Meat and bonemeal, made from rendered carcasses and once used in highprotein

animal feed.

MMBM = Mammalian MBM. Under EU regulations, this is not permitted to be fed to

ruminant mammals.

MRM = Mechanically Recovered Meat, scraped from bones and connective tissue.

OTM = Over Thirty Month scheme in the UK prohibiting older cattle from the food

chain.

PrP = The prion protein

PrPC = Normal cellular prion

PrPres = Abnormal prions, defined by resistance to degradation with protein

enzymes.

PrPSc = Abnormal prions, presumed to be similar to those found in scrapie.

SBO = Specified Bovine Offal, cattle offal prohibited from human food supplies.

SEAC = the Spongiform Encephalopathy Advisory Committee, a UK governmentappointed

expert advisory group.

SRM = Specified Risk Material, ruminant offal prohibited from human food supplies.

SSC = the Scientific Steering Committee, an EC-appointed expert advisory group.

TSE = Transmissible Spongiform Encephalopathy, a general term for the family of

diseases including BSE, scrapie, CWD and vCJD.

vCJD = the new form of Creutzfeldt Jakob Disease which has been linked to BSE in

cattle. (The ‘v’ stands for ‘variant’ or ‘new variant’.)

References

1 Bocharova OV, Breydo L, Salnikov VV, Gill AC, Baskakov IV. Synthetic prions generated in

vitro are similar to a newly identified subpopulation of PrPSc from sporadic Creutzfeldt-Jakob

Disease. Protein Sci. 2005 May;14(5):1222-32. Epub 2005 Mar 31.

2 Castilla J, Saa P, Hetz C, Soto C. In vitro generation of infectious scrapie prions. Cell. 2005

Apr 22;121(2):195-206.

3 Scott MR, Peretz D, Nguyen HO, Dearmond SJ, Prusiner SB. Transmission barriers for

bovine, ovine, and human prions in transgenic mice. J Virol. 2005 May;79(9):5259-71.

4 Narang HK, Dagdanova A, Xie Z, Yang Q, Chen SG. Sensitive detection of prion protein in

human urine. Exp Biol Med (Maywood). 2005 May;230(5):343-9.

5 See http://www.freedomtocare.org/page147.htm for a statement from Dr Harang in 2000.

6 Inoue Y, Yamakawa Y, Sakudo A, Kinumi T, Nakamura Y, Matsumoto Y, Saeki K,

Kamiyama T, Onodera T, Nishijima M. Infection route-independent accumulation of splenic

abnormal prion protein. Jpn J Infect Dis. 2005 Apr;58(2):78-82.

7 Anon. News and Reports: Discriminating BSE from scrapie in sheep. The Veterinary Record

156:527 (2005); and DEFRA press release 186/05, 4 April 2005.

26

8 Tomkinson A, Phillips P, Scott JB, Harrison W, De Martin S, Backhouse SS, Temple M. A

laboratory and clinical evaluation of single-use instruments for tonsil and adenoid surgery.

Clin Otolaryngol. 2005 Apr;30(2):135-42.

9 SEAC meeting, 3 March 2005. See http://www.seac.gov.uk/minutes/final86.pdf .

10 Rajak SN, Paul J, Sharma V, Vickers S. Contamination of disposable tonometer prisms

during tonometry. Eye. 2005 Apr 15; [Epub ahead of print].

11 Eloit M, Adjou K, Coulpier M, Fontaine JJ, Hamel R, Lilin T, Messiaen S, Andreoletti O,

Baron T, Bencsik A, Biacabe AG, Beringue V, Laude H, Le Dur A, Vilotte JL, Comoy E,

Deslys JP, Grassi J, Simon S, Lantier F, Sarradin P. BSE agent signatures in a goat. Vet Rec.

2005 Apr 16;156(16):523-4.

12 Eglin RD, Warner R, Gubbins S, Sivam SK, Dawson M. Frequencies of PrP genotypes in

38 breeds of sheep sampled in the National Scrapie Plan for Great Britain. Vet Rec. 2005 Apr

2;156(14):433-7.

13 Casalone C, Corona C, Crescio MI, Martucci F, Mazza M, Ru G, Bozzetta E, Acutis PL,

Caramelli M. Pathological prion protein in the tongues of sheep infected with naturally

occurring scrapie. J Virol. 2005 May;79(9):5847-9.

14 Halliday S, Houston F, Hunter N. Expression of PrPC on cellular components of sheep

blood. J Gen Virol. 2005 May;86(Pt 5):1571-9.

15 Coore RR, Love S, McKinstry JL, Weaver HR, Philips A, Hillman T, Hiles M, Helps CR, Anil

MH. Brain tissue fragments in jugular vein blood of cattle stunned by use of penetrating or

nonpenetrating captive bolt guns. J Food Prot. 2005 Apr;68(4):882-4.

16 Herde K, Bergmann M, Lang C, Leiser R, Wenisch S. Glial fibrillary acidic protein and

myelin basic protein as markers for the immunochemical detection of bovine central nervous

tissue in heat-treated meat products. J Food Prot. 2005 Apr;68(4):823-7.

17 Kelly DF, Wells GA, Haritani M, Higgins RJ, Jeffrey M. Neuropathological findings in cats

with clinically suspect but histologically unconfirmed feline spongiform encephalopathy. Vet

Rec. 2005 Apr 9;156(15):472-7.

18 Paisley LG, Hostrup-Pedersen J. A quantitative assessment of the BSE risk associated with

fly ash and slag from the incineration of meat-and-bone meal in a gas-fired power plant in

Denmark. Prev Vet Med. 2005 May 10;68(2-4):263-75.

19 Wells GA, Spiropoulos J, Hawkins SA, Ryder SJ. Pathogenesis of experimental bovine

spongiform encephalopathy: preclinical infectivity in tonsil and observations on the distribution

of lingual tonsil in slaughtered cattle. Vet Rec. 2005 Mar 26;156(13):401-7.

20 Early phase of vCJD infection in recipients of blood transfusions, SEAC paper 87/3, SEAC

meeting, London, 21 April 2005.

21 SEAC meeting, London, 21 April 2005.

22 N J Andrews, Incidence of Variant Creutzfeldt-Jakob Disease Onsets and Deaths in the

UK, January 1994 – March 2005. CDSC Statistics Unit, Health Protection Agency. 14 April

2005.

23 The Canadian / AAP, 12 April 2005.

24 CBC / Alberta News, 25 April 2005.

25 B Gorham, Canada Press / Canada.com, 26 April 2005.

26 The Japan Times, 23 April 2005.

27 I Morita, Bloomber.com, 18 April 2005.

28 The Japan Times, 6 April 2005.

29 Agriculture Online (www.agriculture.com) 4 April 2005.

30 The Japan Times Online, 9 April 2005.

31 Kyodo news agency, 5 April 2005.

32 US Newswire, 20 April 2005.

33 R Fabi, Reuters / Yahoo News, 15 April 2005.

34 Reuters, 13 April 2005.

35 United Press International, 13 April 2005.

36 Council of Canadians and Beyond Factory Farming, joint news release, Canada Newswire,

12 April 2005.

37 U.S. Department of Agriculture’s Summary of the Epidemiological Findings of North

American, USDA, April 2005. See

http://www.aphis.usda.gov/lpa/issues/bse/bse_epi_report_4-29-05.doc .

Bovine Spongiform Encephalopathy Positive Cattle

38 L Taylor, Kansas Dept of Agriculture, Agriculture Online, 28 April 2005.

39 A Brodmerkel, Berliner Zeitung, 8 April 2005.

40 J Carleo-Evangelist, NY Times Union, 21 April 2005.

41 United Press International, 28 April 2005.

42 Newsday.com / Associated Press, 29 April 2005.

27

43 NBC / Associated Press, 18 April 2005.

44 E Beckley, Outer Banks Sentinel, North Carolina, 4 May 2005.

45 Tennessean.com, 5 May 2005.

46 News and Reports, The Veterinary Record 156:426-427, 2 April 2005.

47 The Scotsman (Scotsman.com), 6 April 2005.

48 Statement of the BIOHAZ Panel RE : Technical Advice on the United Kingdom application

for application of Moderate Risk in terms of Bovine Spongiform Encephalopathy (BSE),

Statement of the Scientific Panel on Biological Hazards, EFSA 15 March 2005. See

http://www.efsa.eu.int/science/biohaz/biohaz_documents/catindex_en.html .

49 Food Standards Agency, Monthly report of Specified Risk Material and other BSE Control

breaches for March 2005, 20 April 2005.

50 F Urquhart, The Scotsman / Scotsman.com, 19 April 2005.

51 E Thomasson, Reuters / Swissinfo, 21 April 2005.

52 Associated Press / Las Vegas Sun, 21 April 2005.

53 Agence France Presse / Khajeel Times, 5 April 2005.

54 The Japan Times, 10 April 2005.

55 United Press International, 7 April 2005.

56 A Zimm, Bloomber.com, 12 April 2005.

57 BBC News Online, 13 April 2005.

58 J Meikle, The Guardian, 22 April 2005.

59 Office International des Epizooties [www.oie.int]

60 An excellent source is J Braakman [www.bovine.nl].

61 European Commission website,

[http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm]

62 European Commission website,

[http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm]

63 DEFRA BSE Information, Weekly statistics.

64 For details of this programme, see K Taylor, MAFF Programme to Eradicate BSE in the

United Kingdom, in The Mad Cow Crisis (S C Ratzan, Ed), UCL Press, London, 1998.

65 MAFF gave figures for UK cattle herds as totalling 10.878m head in 2000 (11.281m in

1999, and 11.237m in 1998) Agra Europe Weekly, 30 March 2001. Adult cattle total some

5.3m in 2001, according to the table of figures on testing of animals, FSA Press Release

2001/0132, 3 August 2001.

66 BSE: Measures taken by the UK, DEFRA Monthly Report, and subsequent DEFRA

notices.

67 Paper 80/4, SEAC meeting, London, 26 November 2003.

68 European Commission website,

[http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm]

69 European Commission website,

[http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm]

70 European Commission website,

[http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm]

71 European Commission website,

[http://europa.eu.int/comm/food/fs/bse/testing/bse_results_en.htm]

72 DEFRA, www.defra.gov.uk/animalh/bse/bse-science/level-4-scrapie.html, Incidence of

Scrapie.

73 J Ironside, CJD Surveillance Centre, Statement to SEAC meeting, London, 3 March 2005.

74 H Ward, National CJD Surveillance Unit, Statement to SEAC meeting, London, 25

February 2004.

75 Reuters, 4 Feb 2005.

76 Reuters, 4 March 2005.

77 E Thomasson, Reuters / Swissinfo, 21 April 2005.

78 CJD Surveillance Centre.

79 CJD Surveillance Centre.

http://www.which.net/campaigns/food/safety/bse_reports/bserep0405.pdf

TSS




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