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". 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" . 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 ) or 21 months
(Japan ) 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 . 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" . 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 . 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 . 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" . 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 ..
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" (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" . 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
. 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" 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 . 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
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