[Federal Register Volume 61, Number 156 (Monday, August 12, 1996)]
[Rules and Regulations]
[Pages 41730-41733]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-20450]
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DEPARTMENT OF AGRICULTURE
Animal and Plant Health Inspection Service
9 CFR Part 78
[Docket No. 96-015-2]
Brucellosis; Approved Brucella Vaccines
AGENCY: Animal and Plant Health Inspection Service, USDA.
ACTION: Affirmation of interim rule as a final rule.
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SUMMARY: We are adopting as a final rule, without change, an interim
rule that amended the brucellosis regulations to remove the requirement
that an approved brucella vaccine be, among other things, a Brucella
abortus Strain 19 product. The interim rule allowed for the use of
vaccines that have been developed using strains of Brucella other than
Brucella abortus Strain 19. Specifically, the interim rule allowed the
RB51 brucella vaccine, which was licensed for use in cattle by the U.S.
Department of Agriculture in February 1996, to be used in the
cooperative State/Federal brucellosis eradication program.
EFFECTIVE DATE: The interim rule was effective on March 26, 1996.
FOR FURTHER INFORMATION CONTACT: Dr. M.J. Gilsdorf, National
Brucellosis Epidemiologist, Cattle Diseases and Surveillance Staff, VS,
APHIS, 4700 River Road Unit 36, Riverdale, MD 20737-1228, (301) 734-
7708; E-mail: mgilsdorf@aphis.usda.gov.
SUPPLEMENTARY INFORMATION:
Background
In an interim rule effective March 26, 1996, and published in the
Federal Register on April 1, 1996 (61 FR 14237-14239, Docket No. 96-
015-1), we amended the brucellosis regulations in 9 CFR part 78 by
revising the definition of approved brucella vaccine and amending the
definitions of official adult vaccinate, official calfhood vaccinate,
and official test to provide for the use of approved brucella vaccines
that have been developed using strains
[[Page 41731]]
of brucellosis other than Brucella abortus Strain 19. That action was
necessary to allow the RB51 brucella vaccine, which was licensed for
use in cattle by the U.S. Department of Agriculture in February 1996,
to be used in the cooperative State/Federal brucellosis eradication
program.
Comments on the interim rule were required to be received on or
before May 31, 1996. We did not receive any comments by that date. The
facts presented in the interim rule still provide a basis for the rule.
This action also affirms the information contained in the interim
rule concerning Executive Orders 12372 and 12778 and the Paperwork
Reduction Act.
Executive Order 12866 and Regulatory Flexibility Act
This rule has been reviewed under Executive Order 12866. For this
action, the Office of Management and Budget has waived its review
process required by Executive Order 12866.
This document makes final an interim rule effective March 26, 1996,
and published in the Federal Register on April 1, 1996. In that interim
rule, we stated that timely compliance with sections 603 and 604 of the
Regulatory Flexibility Act (5 U.S.C. 601 et seq.) was impracticable due
to the need to make the rule effective in time for U.S. cattle raisers
to use RB51 to vaccinate the spring crop of calves before the calves
were turned out for summer pasture. We further stated, however, that
the final rule would include an analysis of the economic impact of the
rule on small entities and would address any comments we received on
the economic impact of the rule on small entities. We did not receive
any comments regarding the impact of the rule on small entities, but we
have prepared an analysis of the economic impact of the rule on small
entities.
Currently available Brucella abortus Strain 19 brucella vaccines
cause vaccinated animals to produce antibodies that are
indistinguishable on standard diagnostic tests from the antibodies
produced by animals infected with brucellosis. Therefore, when a
vaccinated animal is tested, the results of the test indicate that the
animal may be a brucellosis reactor, even though the animal is not
infected with the disease; this misleading result is known as a ``false
positive.'' State or Federal animal health personnel must trace those
animals to their herds of origin to determine whether or not the herd
is actually affected with brucellosis. Because the RB51 vaccine does
not cause vaccinated cattle to produce those interfering antibody
titers, replacing the Strain 19 vaccines with the RB51 vaccine will
almost entirely eliminate the costs associated with the retesting and
traceback of false-positive reactors.
In fiscal year (FY) 1995, about 6.7 million cattle (primarily
calves between 4 and 12 months of age) were vaccinated against
brucellosis using Strain 19 vaccine. Although brucellosis is expected
to be eradicated in domestic cattle within 3 years, it is likely that
some States will continue to encourage herd owners to vaccinate higher-
risk cattle herds.
In FY 1995, blood samples taken from approximately 5,900 head of
cattle at market or slaughter under the Market Cattle Identification
(MCI) program tested positive for the brucella bacteria, requiring
retesting and traceback to the herds of origin. By far, most of the
positive tests proved to be false; only about 100 cattle were found to
be infected. If the RB51 vaccine had been used, about 99 percent of the
false-positive tests would not have occurred, so about 5,742
unnecessary tracebacks and herd tests would have been prevented.
An additional 6,000 of the MCI-sampled cattle had titer levels less
than that indicative of a positive reaction, but sufficiently high to
cause suspicion of the disease. An estimated 50 percent of these cattle
also were traced back to their herds of origin, and the herd owners
were contacted in about one-third of the cases. Again, the use of RB51
would have prevented about 99 percent (5,940) of the suspect titers,
thus precluding the need for about 2,970 tracebacks, about 1,980 herd
owner contacts, and about 990 herd tests.
The brucellosis ring test (BRT) for dairy herds in FY 1995
indicated 732 suspected cases of the disease. After retesting, 235
herds were subsequently blood-tested, but only 2 herds were found to be
affected. Hence, 730 of the cattle tested were false-positive. Tracing
and blood testing of their herds of origin would not have been
necessary if the RB51 vaccine had been used.
For all three categories--MCI reactors, MCI suspects, and BRT
reactors--the use of RB51 vaccine instead of Strain 19 will eliminate
nearly all false-positive reactors. The potential savings can be
estimated by considering resources currently devoted to tracebacks, lab
tests, and related activities.
Estimated time required by major types of field work for which
there will be resource savings when RB51 replaces Strain 19 are shown
in Table 1.
Table 1.--Estimated Average APHIS/State Field Hours Spent on MCI and BRT
Tests and Tracebacks
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Staff
Activity hours
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Epidemiology................................................... 10.15
Contacting herd owners......................................... 2.23
Contacting veterinarians....................................... 1.00
MCI herds of origin locating................................... 5.10
MCI herds of origin testing.................................... 12.21
BRT suspicious herds blood testing............................. 13.00
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In Table 2, the time requirements are multiplied by the estimated
number of Strain 19 false-positives per year, yielding a potential
field staff hour savings from using RB51 totaling 255,956 hours per
year. Assuming an average staff hour cost of $27.85 (salary and
benefits, plus support), annual field work savings for APHIS and
cooperating States from replacing Strain 19 by RB51 would be about
$7,128,000 (255,956 hours x $27.85 per hour). With reduced numbers of
cattle vaccinated following brucellosis eradication, the number of
false-positive reactors if Strain 19 were used would also be fewer;
therefore, annual potential savings in subsequent years could be
estimated at about one-half of current savings, or about $3,564,000,
for field work that would no longer be necessary when RB51 is used in
place of Strain 19.
Table 2.--Estimated Annual Field Staff Hour Savings to APHIS and States
From Using RB51 in Place of Strain 19, Based on FY 1995 and FY 1996 Data
------------------------------------------------------------------------
Estimated
number of
Activity Strain 19 Hours per Total hours
false activity
positives
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Epidemiology:
MCI reactors................. 5,742 10.15 58,281
[[Page 41732]]
MCI suspects \1\............. 2,970 10.15 30,146
BRT reactors................. 730 10.15 7,410
Contacts with herd owners:
MCI reactors................. 15,742 2.23 12,805
MCI suspects \2\............. 1,980 2.23 4,415
BRT reactors................. 730 2.23 1,628
Contact with veterinarians: \3\
MCI reactors................. 4,307 1.00 4,307
MCI suspects................. 297 1.00 297
BRT reactors................. 548 1.00 548
Locating herds of origin:
MCI reactors................. 5,742 5.10 29,284
MCI suspects \4\............. 2,970 5.10 15,147
Testing herds of origin:
MCI reactors................. 5,742 12.21 70,110
MCI suspects \5\............. 990 12.21 12,088
Testing suspect herds:
BRT reactors................. 730 13.00 9,490
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\1\ Epidemiology is conducted for an estimated 50 percent of MCI
suspects.
\2\ An estimated one-third of herd owners are contacted for MCI
suspects.
\3\ Veterinarians are contacted for an estimated 75 percent of MCI
reactors, 5 percent of MCI suspects, and 75 percent of BRT reactors.
\4\ Herds of origin are located for an estimated 50 percent of MCI
suspects.
\5\ Herds of origin for MCI suspects are tested for an estimated one-
third of those located.
In addition to field staff savings, MCI laboratory costs associated
with Strain 19 false-positive tests will also be eliminated by the use
of RB51 vaccine. The concentration immunoassay technology (CITE') test
costs $10.00, which is paid either by the State or the herd owner,
depending on a particular State's regulations. The costs of other
official tests--e.g., the Rivanol, particle concentration fluorescence
immunoassay (PCFIA), and manual complement-fixation (CF) tests--are
estimated to total about $15 to $20 per tested animal, including
overhead. As shown in Table 3, a savings of more than $320,000 will
result from the use of RB51, assuming an overall cost for all
laboratory work of $27.50. As with the field staff savings, we can
assume that laboratory savings of at least one-half this amount, or
$160,000 per year, will be realized after eradication of brucellosis,
given the expected reduction in the number of cattle vaccinated.
Table 3.--Estimated Savings in Laboratory Costs Resulting From the Use
of RB51 Vaccines in Place of Strain 19 Vaccines
------------------------------------------------------------------------
Estimated
number of Average
Strain 19 cost per
Category false set of Total cost
positives analyses
per year
------------------------------------------------------------------------
MCI reactors..................... 5,742 $27.50 $157,905
MCI suspects..................... 5,940 27.50 163,350
------------------------------------------------------------------------
Estimated combined field and laboratory gross savings from using
RB51 vaccine total nearly $7.45 million per year at current levels of
vaccination. After brucellosis has been eradicated, gross savings of at
least $3.7 million per year can be expected. Except in those States
where owners are directly charged for the CITE test, APHIS
and cooperating States bear the costs associated with tracebacks and
other activities required by false-positive tests. The general public,
therefore, will benefit from the expected savings in government
expenditures. Affected producers, most of whom can be considered small
entities (gross annual incomes of less than $500,000), will also
benefit by not having to spend time and resources in gathering their
herds for testing to follow up on false-positive reactors and suspects.
The RB51 vaccine costs more than the Strain 19 vaccine, $0.42 per
dose compared to $0.30 per dose. Based on the number of vaccinations
given in FY 1995, this cost difference amounts to $804,000 per year.
Assuming an average of about 4 million vaccinations per year following
brucellosis eradication, the additional cost of the RB51 vaccine will
be about $480,000 after eradication. The net benefit of replacing
Strain 19 by RB51 is therefore estimated at about $6.6 million per year
before brucellosis eradication, and about $3.2 million per year
afterwards.
Lastly, because the RB51 vaccine will not cause false-positive
titers as does Strain 19, it can be used to vaccinate older animals
that might not otherwise be vaccinated. Although this advantage is not
quantified, it will be a definite benefit for producers and States.
[[Page 41733]]
Under these circumstances, the Administrator of the Animal and
Plant Health Inspection Service has determined that this action will
not have a significant economic impact on a substantial number of small
entities.
List of Subjects in 9 CFR Part 78
Animal diseases, Bison, Cattle, Hogs, Quarantine, Reporting and
recordkeeping requirements, Transportation.
PART 78--BRUCELLOSIS
Accordingly, we are adopting as a final rule, without change, the
interim rule that amended 9 CFR part 78 and that was published at 61 FR
14237-14239 on April 1, 1996.
Authority: 21 U.S.C. 111-114a-1, 114g, 115, 117, 120, 121, 123-
126, 134b, and 134f; 7 CFR 2.22, 2.80, and 371.2(d).
Done in Washington, DC, this 6th day of August 1996.
Terry L. Medley,
Administrator, Animal and Plant Health Inspection Service.
[FR Doc. 96-20450 Filed 8-9-96; 8:45 am]
BILLING CODE 3410-34-P
