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Mad Cow: Consumers
Union calls on USDA to release data
Group raises serious concerns
about credibility of government surveillance program
Consumers Union
July 26, 2005 at 09:09
Consumers Union is raising serious questions
about the credibility of the U.S. Department of
Agriculture’s (USDA) expanded voluntary mad-cow
surveillance program and is asking the agency
to release details on the more than 400,000 cattle
tested. In a letter sent to Agriculture Secretary
Mike Johanns today, the group cited serious deficiencies
in the earlier years of the program uncovered
by the Office of Inspector General.
Consumers Union specifically requested data on:
· The geographic location of sampled cattle
(including the state where the cow was born, raised,
and slaughtered)
· The age of the cattle tested (CU currently
supports testing of all cattle above 20 months)
· The disease/high-risk status of the
cattle (for example, did they show symptoms of
central nervous system disease, which are common
symptoms of mad cow).
"The government keeps telling Americans
that they can trust that their beef is safe from
mad cow, even going so far as to say that finding
BSE is like searching for a needle in a haystack.
Yet, since the agency has so far failed to publicly
disclose any information whatsoever about the
details of the program, it makes us wonder how
meaningful their search for the disease is at
all," says Dr. Michael Hansen, PhD, a Senior
Scientist with Consumers Union.
"We want to know exactly which cattle were
tested and whether or not they really represent
the most valid scientific sampling of the highest-risk
animals from across the country. If the USDA wants
to truly reassure the American people, they should
answer our questions. Their failure to do so would
make us wonder what the agency is hiding,"
adds Hansen.
Consumers Union’s letter comes after the
USDA’s announcement last month that a cow
originally pronounced last November to be negative
for mad cow disease turned out upon re-testing
to be positive.
A copy of the letter follows:
July 25, 2005
Hon. Mike Johanns
Secretary of Agriculture
US Department of Agriculture
1400 Independence Avenue, SW
Washington, DC 20250
Dear Secretary Johanns:
We are writing to you because we are concerned
about the meaningfulness, credibility and lack
of transparency of the expanded BSE Surveillance
Program (hereafter referred to as the "Program")
that has been carried out by the U.S. Department
of Agriculture’s Animal Plant Health Inspection
Service (APHIS) beginning June 1, 2004. The Office
of Inspector General’s (OIG’s) Audit
Report on the first phase of the BSE Surveillance
Program (e.g. 1990-2004) raises serious questions
about the quality of the data gathered under the
Surveillance program.
We are concerned that there are potentially serious
methodological problems and/or flawed assumptions
involved with the expanded BSE Surveillance Program.
These methodological problems are that sampled
brains may not be a proper geographical sample
of the high-risk population, and that the highest
risk brains may not be included.
The failure of the USDA to release any data whatsoever
about the details of the Program, such as location
of sampled cattle (state where born, raised, slaughtered),
age, and disease/high-risk status (e.g. did it
show symptoms of central nervous system [CNS]
disease) heightens concerns about whether the
sampling is being conducted in a valid matter.
Geographic distribution
We are concerned about whether adequate geographic
distribution is being achieved in the Program.
A basic problem is that participation in the Program
is voluntary. The stated goal of the USDA’s
expanded BSE surveillance program is "to
collect samples from as many adult cattle from
the high-risk population as possible in 12-18
months while ensuring that there is a statistically
appropriate geographical representation of the
adult cattle population in the United States"[1]
. For this sampling program to be statistically
valid, the cattle chosen for testing must be a
random geographical sample of the high-risk population.
To ensure a random sample, the Program should
be mandatory. The OIG’s Audit Report on the
first phase of the Program (e.g. 1990-2004), found
that prior to the start of the expanded surveillance
program (e.g. June 1, 2004), sample collection
was not geographically random, but rather was
"concentrated in a few slaughter establishments
and renderers in a few States." In addition
the OIG noted that "APHIS has no contingency
plans if geographical targets are not obtained"[2]
. Thus, we ask USDA to release information on
the geographical location of all the cattle that
are sampled as part of the Expanded BSE Surveillance
Program.
Age
The age of sampled animals is also important.
Although BSE is thought typically to infect animals
at a very young age, the disease can have a long
incubation period and is usually detected in older
animals (detection is more difficult in young
animals incubating the disease). Although animals
as young as 20 months (United Kingdom[3] ) or
21 months (Japan[4] ) have been found to test
positive for BSE, the detected disease prevalence
is higher for older animals. The Texas cow confirmed
with BSE last month was about 12 years old. Dairy
cattle are at higher risk for BSE compared to
beef cattle, because, being productive for a number
of years, they are usually slaughtered at an older
age than beef cattle. Dairy cattle are also more
likely to receive protein supplements in their
feed (to support their milk production) than beef
cattle. Some 80% of the BSE cases in the UK occurred
in dairy cattle[5] . Thus, we feel that all elderly
dairy cattle should be sampled for BSE. Consequently,
we ask what are the ages of all the cattle that
have been sampled for BSE?
High-risk cattle
Another potentially serious methodological problem
with the expanded Program is whether it includes
the highest risk animals. According to USDA’s
2004 Expanded Surveillance Plan, the high-risk
population to be tested should include "adult
cattle showing clinical signs involving the central
nervous system (CNS), and dead and non-ambulatory
cattle where the clinical signs cannot be adequately
evaluated"[6] .
But not all animals in this high-risk population
are equally high risk. The highest risk animals
are those exhibiting symptoms consistent with
BSE, such as rabies-suspect animals that test
negative for rabies, and animals exhibiting symptoms
of CNS disease. In fact, when the USDA first began
the surveillance program in 1989/1990, there were
only two categories of cattle in the high-risk
category: rabies-suspect but rabies-negative cattle
and cattle exhibiting CNS symptoms. It wasn’t
until 1993 that USDA added downer (e.g. non-ambulatory)
cows to the list of high-risk cattle that were
to be sampled for BSE testing.
Rabies-negative cattle
All aggressive animals are tested for rabies.
If the test is negative, then some other condition,
possibly BSE, is responsible for the aggressive
behavior. Thus, rabies-negative cattle are perhaps
the highest risk cattle of all. USDA states that
all rabies-suspect cattle that test negative for
rabies should be tested for BSE[7] . However,
the OIG’s Audit Report on the first phase
of the Program (e.g. 1990-2004), points out that
only a small percentage of rabies-suspect, rabies-negative
cattle were actually tested for BSE. The OIG report
surveyed five state laboratories and found that
only 16% of the rabies-negative samples (94 of
586) from those states were sent for BSE testing[8]
.
The OIG noted that there was neither a requirement
for rabies-negative cattle to be tested nor a
formal mechanism in place to routinely submit
such samples for testing. The OIG noted that,
of 175 rabies-negative cattle tested for rabies
at a laboratory in Iowa—in the same state
as USDA’s National Veterinary Services Laboratory
(NVSL)—during FY 02-03, only two were sent
to NVSL for testing for BSE. Indeed, the OIG noted
that as of 2004 officials from South Dakota were
not even aware that rabies-negative cattle could
be sent for BSE testing! Finally, the OIG noted
that "As of June 1, 2004, APHIS has not provided
us with any detailed plans on how samples for
this targeted high-risk group will be obtained"[9]
.
Since this is perhaps the highest risk group
for BSE, we must ask how many rabies-negative
cattle occurred in the U.S. from June 1, 2004
to July 1, 2005 and how many of these rabies-negative
cattle were actually tested for BSE? If not all
rabies-negative cattle, considered to be the highest-risk
cattle, are sampled, then we question how useful
the data are on the rest of the animals.
Cattle with CNS symptoms
Cattle that are condemned at slaughter for CNS
symptoms are also considered to be among the highest-risk
cattle for BSE. According to the OIG’s report,
USDA’s Food Safety Inspection Service (FSIS)
condemned 680 cattle for CNS symptoms between
fiscal year 2002 and 2004. Of these 680 cattle
357, or 52%, were classified as adults. Using
APHIS records, OIG found that only 162 cattle
condemned for CNS symptoms were tested for BSE
in this period; this represents 45% of the adult
cows (162 of 357) or 24% of all cattle (162 of
680) condemned for CNS symptoms.
In April, 2004, a cow condemned for CNS symptoms
at a slaughter plant (Lone Star Beef) in San Angelo,
TX was not tested for BSE, even though the FSIS
officials at the plant had asked that the animal
be tested for BSE[10] . Apparently, an APHIS official
in Austin, Texas had overruled the FSIS officials
at the plant.
As a result of this incident, APHIS and FSIS
issued a joint notice in May 2004 (FSIS Notice
28-04) which stated that henceforth all animals
condemned for CNS symptoms would be tested for
BSE, regardless of the age of the animal. We thus
ask how many cattle were condemned for CNS symptoms
between June 1, 2004 and July1, 2005? How many
of these cattle were actually tested for BSE?
Cattle that died on the farm
As the OIG report stated, "Identifying truly
high-risk cattle that die on the farm may be complicated
by the reluctance of producers to submit them
and the motivation [of others] to mischaracterize
low risk carcasses as "high risk" since
only the latter may qualify for reimbursement.
These inherent problems can lead to an understatement
of the projected maximum BSE prevalence rates
for truly high-risk cattle and a reduced chance
of detecting BSE, if it exists"[11] (OIG,
2004: pg. 16).
According to USDA’s 2004 Expanded Surveillance
Plan, the high-risk animals that die on the farm
make up the largest component of USDA’s targeted
high-risk population. According to the USDA’s
Expanded Surveillance Plan, 56% of the 446,000
adult cattle in the "high risk" group
will be "adult cattle that die on farm each
year due to unknown reasons or reasons that could
be consistent with BSE-related clinical signs"[12]
.
In the General Accounting Office (GAO) audit
report on the FDA and USDA actions on BSE, GAO
pointed out that USDA didn’t sample many
animals that died on the farm and also didn’t
separately track brains from such animals; such
animals were counted in the downer cow category[13]
. The OIG report noted that "we could not
determine if samples from this targeted group
[cows that died on the farm] have been obtained
in the past"[14] italics added. We note that
the November, 2004 cow that ultimately tested
positive has now been found to be a "dead"
cow—it showed up dead at the slaughter plant
and was redirected to the Champion Pet food plant
in Waco, Texas[15] . Thus we ask How many cattle
died on the farm in the U.S. between June 1, 2004
and July 1, 2005? How many dead cattle were actually
tested for BSE?
Conclusion
These very important basic facts about the USDA’s
Expanded Surveillance Program are essential to
an assessment of the validity of the Program.
The American public, and America’s trading
partners, have had their faith shaken in USDA’s
Surveillance Program by the disclosure of severe
shortcomings in its confirmation procedures. These
shortcomings led USDA to announce on November
22, 2004 that a cow was a confirmed negative when
seven months later proper testing showed it was,
in fact, positive for BSE. In order to maintain
trust in its Surveillance Program, USDA should
immediately answer our questions and disclose
to the public the details of the Program.
Sincerely,
Michael Hansen, Ph.D. Senior Scientist
Jean Halloran Director, Food Policy Initiatives
[1] USDA, 2004, pg. 1. at http://www.aphis.usda.gov/lpa/issues/bse/BSE_Surveil_Plan03-15-04.pdf
[2] USDA/OIG. 2004. Audit Report Animal and Plant
Health Inspection Service and Food Safety and
Inspection Service Bovine Spongiform Encephalopathy
(BSE) Surviellance Program – Phase I. Report
No. 50601-9-KC, August 2004. 60pp. Washington,
D.C.
[3] http://www.defra.gov.uk/animalh/bse/statistics/bse/yng-old.html
[4] Yamakawa, Y. et al. for the Expert Committee
for BSE Diagnosis, Ministry of Health, Labour
and Welfare of Japan. 2003. Atypical proteinase
K-resistant prion protein(PrPres) observed in
an apparently healthy 23-month old Holstein steer.
Japan Journal of Infectious Disease 56:221-222.
[5] see http://www.defra.gov.uk/animalh/bse/statistics/bse/general.html
[6] USDA, 2004, Op cit
[7] USDA, 2004, Op cit
[8] USDA/OIG. 2004. Op cit
[9] pg. 19, USDA/OIG. 2004. Op cit
[10] Yovich, D. 2004. USDA's San Angelo vets
and techs ordered not to test suspect cow. Meatingplace.com,
May 5. At http://www.meatingplace.com
[11] pg. 16, USDA/OIG. 2004 Op cit.
[12] USDA, 2004, at http://www.aphis.usda.gov/lpa/issues/bse/BSE_Surveil_Plan03-15-04.pdf
[13] GAO, 2002. Mad Cow Disease: Improvements
in the Animal Feed Ban and Other Regulatory Areas
Would Strengthen U.S. Prevention Efforts. GAO-02-183.
59pp.
[14] USDA/OIG. 2004 Op cit
[15] Patel, P. and D. Ivanovich. 2005. Mad cow
traced to Waco. Houston Chronicle, June 30, 2005
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