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**Assessment of the Risk of Introduction of Contagious Equine Metritis
(CEM) through the Extended Importation of Noncompetitive Entertainment
Horses from CEM-affected countries**

**September 2006**

#   {#section .unnumbered}

# TABLE OF CONTENTS

[**TABLE OF CONTENTS 2**](#table-of-contents)

[ACRONYMS AND ABBREVIATIONS 3](#acronyms-and-abbreviations)

[EXECUTIVE SUMMARY 4](#executive-summary)

[INTRODUCTION 5](#__RefHeading___Toc144786530)

[RISK ASSESSMENT GUIDELINES 6](#risk-assessment-guidelines)

[RISK ASSESSMENT 6](#risk-assessment)

[Hazard Identification 6](#hazard-identification)

[Release Assessment 7](#release-assessment)

[Exposure Assessment 9](#exposure-assessment)

[Consequence Assessment 10](#consequence-assessment)

[Risk Estimation 11](#risk-estimation)

[Data Limitations 11](#data-limitations)

[TRACKING IMPORTED HORSES 11](#tracking-imported-horses)

[FURTHER CONSIDERATIONS 11](#further-considerations)

[SUMMARY 12](#summary)

[BIBLIOGRAPHY 13](#bibliography)

[APPENDICES 15](#appendices)

[Appendix 1: CEM Temporary Isolation Facility Checklist
15](#appendix-1-cem-temporary-isolation-facility-checklist)

[Appendix 2: Sample Compliance Agreement
18](#appendix-2-sample-compliance-agreement)

#  

# ACRONYMS AND ABBREVIATIONS

AHT Animal Health Technician

AO Area Office

APHIS Animal and Plant Health Inspection Service

AVIC Area Veterinarian in Charge

C&D Cleaning and Disinfection

CEM Contagious Equine Metritis

CEMO Contagious Equine Metritis Organism

CF Complement Fixation

CFR Code of Federal Regulation

ITS Import Tracking System

NAIS National Animal Identification System

NCIE National Center for Import and Export

OIE World Organization for Animal Health (formerly known as Office
International des Epizooties)

PCR Polymerase Chain Reaction

RFID Radio Frequency Identification Device

UK United Kingdom

US United States

USAHA United States Animal Health Association

USDA United States Department of Agriculture

VMO Veterinary Medical Officer

VS Veterinary Services

# EXECUTIVE SUMMARY

The purpose of the evaluation described in this report is to assess the
risk of allowing the extended importation and isolation of
noncompetitive entertainment horses from countries affected by
Contagious Equine Metritis (CEM) without requiring CEM testing. In
addition, the evaluation included an examination of the risk of the
United States Department of Agriculture (USDA) losing track of these
horses during extended importation. Noncompetitive entertainment horses
perform in circuses, theatrical performances or performing troupes, and
are used solely for public exhibition and entertainment with no
competition trials occurring between horses. CEM is a bacterial disease
of all equids that is primarily transmitted by asymptomatic carrier
animals (usually stallions) via breeding. The United States is CEM free.

Currently,the USDA's Animal and Plant Health Inspection Service (APHIS)
rules concerning import of horses from CEM-affected countries do not
specifically address the entry of noncompetitive entertainment horses.
Most of these horses currently enter the United States under an
exception to CEM testing intended for competitive horses entering for
less than 90 days. These horses are subject to extensive restrictions in
the United States. Performance schedules often do not match this 90-day
window, leading troupes to request extensions. The National Center for
Import and Export (NCIE) within APHIS is considering developing rules
specifically for noncompetitive entertainment horses that allow entry
without completion of CEM testing to standardize the process. The import
requirements currently being developed by NCIE for noncompetitive
entertainment will closely follow the requirements for competitive
horses, with the major exception of the clause governing the length of
stay.

The risk that horses imported from CEM-affected countries will have CEM
is not easily determined, as reliable statistics concerning the
prevalence of CEM are not available. The risk of exposure of U.S. horses
to CEM posed by the extended importation of noncompetitive entertainment
horses is extremely small, though, assuming there is compliance with the
requirements of the import permit. Therefore, the risk posed by allowing
the extended importation of noncompetitive entertainment horses from CEM
affected countries is extremely low, with the application of the
restrictions described.

The risk that the USDA will lose track of these imported horses while in
country for extended periods is more difficult to characterize. However,
due to the extensive supervision and involvement of APHIS personnel and
the accredited veterinarian, the risk that the USDA will lose track of
these horses is extremely low. The use of a high quality individual
animal identification system along with good communication between the
importer, NCIE, APHIS field personnel, and the accredited veterinarian
will be important in maintaining control of these imported animals.

# 

#  

[]{#__RefHeading___Toc144786530 .anchor}**INTRODUCTION**

Currently, USDA-APHIS rules concerning Contagious Equine Metritis (CEM)
prohibit importation of any horses from CEM countries except for: (1)
wild (non-domesticated) species of equidae if they are unlikely to come
in contact with domesticated horses used for breeding, (2) geldings, (3)
weanlings or yearlings, (4) Spanish Pure Breed horses imported for
permanent entry subject to proof of CEM freedom by biologic testing and
other mitigations, (5) stallions or mares over 731 days of age imported
for permanent entry subject to proof of CEM freedom by biologic testing
and other mitigations, (6) horses temporarily exported from the United
States or from another region not known to be affected with CEM to a
region with CEM and demonstrate proof of CEM freedom by biologic testing
and other mitigations, and (7) horses over 731 days of age imported into
the United States for no more than 90 days to compete in specific events
(Title 9 Code of Federal Regulations \[CFR\] Section 93.301 \[c\]
\[2\]). The latter are exempt from biologic testing but subject to other
mitigations (restrictions). Horses for non-competitive entertainment
purposes are not mentioned explicitly in the aforementioned rule. The
National Center for Import and Export (NCIE) receives requests from
importers for entry of horses for such purposes. Noncompetitive
entertainment horses perform in circuses, theatrical performances or
performing troupes and are used solely for public exhibition and
entertainment with no competition trials occurring between horses.

Noncompetitive entertainment horses do not always fit well into any of
the categories of exception listed above, particularly concerning
duration of entry. NCIE is developing a rule that addresses CEM entry
requirements for noncompetitive entertainment horses for a number of
reasons. The effort to evaluate, develop, monitor and maintain these
types of special waivers requires a significant commitment of staff time
for the USDA, particularly since the terms under which these waivers are
negotiated on an individual basis. The horse industry has expressed
concern that these waivers are granted under political pressure and
without their support. In addition the United States Animal Health
Association (USAHA) passed a resolution on November 6, 2005 encouraging
the development of regulations for the importation of noncompetitive
entertainment horses from countries affected with CEM. (USAHA, 2005)

Noncompetitive entertainment horses currently entering the United
States, usually apply for import under the exemption that is applicable
for competitive horses. Currently, the USDA-Veterinary Services
(VS)-NCIE staff must negotiate individual agreements with importers of
noncompetitive entertainment horses that wish to exceed the 90-day
period (NCIE, personal communication). Consequently, the import
requirements currently being developed by NCIE for noncompetitive
entertainment will closely follow the requirements for horses entering
for competitive purposes, with the major exception of the clause
governing the length of stay. NCIE is currently discussing the option of
allowing an indefinite stay, with annual re-evaluation.

The following questions have been posed in preparation for development
of a proposed rule concerning the importation of noncompetitive
entertainment horses from CEM-affected countries:

1.  Is the risk of introduction of the CEM organism to the domestic
    horse population increased by allowing noncompetitive entertainment
    horses originating from CEM-affected countries to stay in the United
    States for periods greater than 3 months? Is the risk increased for
    noncompetitive entertainment horses to encounter domestic horses
    used for breeding while stabling on farms for rest or other purposes
    while on tour if allowed to stay in the United States for periods
    greater than 3 months?

2.  Is the risk of losing track of the location of noncompetitive
    entertainment horses increased if they are allowed to remain in the
    United States for periods greater than 3 months?

The purpose of this risk assessment is to assess the magnitude of the
risk associated with implementing each of the proposed amendments.

# RISK ASSESSMENT GUIDELINES

A risk assessment is a component of risk analysis. Risk analysis
involves the whole process from risk identification, through qualitative
and quantitative assessment of a risk, to the resultant management
decisions and communication to various stakeholders about the decision
that has been (or is to be) made. (Vose 2000) The format of this risk
assessment conforms to the World Organization for Animal Health (OIE)
Code Requirements for Risk Analysis. (World Organization for Animal
Health (OIE) 2005) OIE guidelines state that a risk analysis must start
with hazard identification and then proceed to the four interrelated
steps in a risk assessment (release assessment, exposure assessment,
consequence assessment, risk estimation).

# RISK ASSESSMENT 

## Hazard Identification

CEM, which was first discovered in 1977 in the United Kingdom (UK) and
Ireland, is caused by the gram-negative bacteria *Taylorella
equigenitalis* (also known as CEM organism or CEMO), and can infect all
equids. Outbreaks of CEM have occurred in 25 countries. In the United
States, veterinarians quickly eradicated outbreaks of CEM in
thoroughbreds in Kentucky and Missouri in 1978.

A CEM-like organism, *T. asinigenitalis*, was isolated from one donkey
jack in California and two in Kentucky in 1997 and 1998. These outbreaks
could not be linked epidemiologically. This organism is distinct from
*T. equigenitalis.* (Jang et al., 2001) In 2004, a strain of the
CEM-like organism, similar to the California strain, was isolated from a
3-year-old stallion in Sweden that previously was kept with a donkey
jack. This is the only documented case of natural infection of a
stallion with the CEM-like organism. (Baverud, et al., 2006) The
CEM-like organism has not been shown to produce clinical signs in
horses. The scope of this risk assessment will be limited to the CEM
organism *T. equigenitalis*.

CEMO prefers to colonize the reproductive tract of horses, primarily in
the external genitalia. In stallions, CEMO preferentially colonizes the
urethral fossa and sinus, although it can also be found in the distal
urethra, external surface of the penis and prepuce or within
pre-ejaculatory fluid. In untreated stallions, this colonization can
persist for years. Stallions do not show any clinical signs when
carrying CEMO. Carrier stallions are the most frequent source of new
infections. (Duquesne et al., 2006; Timoney, 2000)

In mares, the incubation period of CEM is between 2 and 12 days. During
the acute stage, inflammation within the uterus leads to an odorless
mucopurulent vulvar discharge that is present for approximately two
weeks. This local inflammation can result in short term infertility. The
chronic stage has milder inflammation within the uterus, and there may
be a scant to inapparent vulvar discharge. In some mares, the organism
becomes established within the external genitalia and/or reproductive
tract. CEMO preferentially colonizes the mucous membranes of the
clitoral sinuses and fossa, and may remain there for months to years.
Mares can also harbor infection within their uterus, although this
occurs less frequently. In these carriers, there are no clinical signs,
but they are contagious. Abortion is a rare sequela to infection.
(Timoney, 1996)

CEM causes high morbidity and spreads easily via breeding. Fatalities
from CEM have not been documented. (USAHA, 1998)

Foals have been infected via transplacental exposure or exposure while
at foot. (Timoney & Powell, 1982) This has not been documented recently
in the published literature, but it is likely that it still plays an
important role in the epidemiology of CEM, particularly in endemic
areas. (Timoney, personal communication)

In the past, spread via fomites was a concern. However, this has not
continued to be a major route of spread because of basic biosecurity
practices. (Timoney, 1996)

The primary method of diagnosis of CEM is culture of the external
genitalia. Multiple sets of cultures are collected over a period of
several days. Polymerase chain reaction (PCR) techniques have been
developed that help increase testing sensitivity and aid in
distinguishing *T. equigenitalis* from *T. asinigenitalis* in culture.
(Premanandh et al., 2003) PCR tests are still in development stages and
have not been fully validated. Serology has not proven to be as helpful
for identifying chronic infection or carrier animals. A complement
fixation (CF) assay is used in limited testing situations with mares
only. Stallions do not produce an antibody response, since they do not
truly become infected. In mares, a transient antibody response occurs 3
to 7 weeks after breeding with an infected stallion. (OIE, 2005b)

There are specific testing requirements detailed in 9 CFR 93.301 that
include requiring stallions to test breed two mares when testing horses
for permanent entry into the United States. These mares are subsequently
tested for CEM using multiple cultures and serology. The use of test
mares has proven to be important in the diagnosis of carriers in import
testing of stallions. In one case study, 2 of 4 infected stallions
cultured negative but were diagnosed as having CEM when one or both of
the test mares cultured positive. (Kristula & Smith, 2004)

There is no effective vaccine available to prevent infection with CEM.
Treatment involves washing of the external genitalia followed by
treatment with topical antibiotics over a period of several days.
Success of treatment is confirmed by repeating testing procedures. The
treatment of stallions is frequently more successful and straightforward
than the treatment of mares. (Timoney, 1996) Several disinfectants
readily inactivate CEMO. Guidelines concerning cleaning and disinfection
are available in 9 CFR 71.7-71.12. (C&D).

## Release Assessment

A release assessment describes the biological pathway(s) necessary for
an importation activity to introduce pathogenic agents into a particular
environment and estimates the probability of that occurring. (OIE 2005).

CEM can be spread via indirect routes (fomites), transplacentally, and
by breeding. Within the framework of this risk assessment, the only
viable pathway of release (entry) of the bacteria for exposure of U.S.
horses to CEM is via breeding. Fomites have been most important in the
past in situations where horses were receiving genital examinations with
little or no biosecurity procedures exercised between animals. As
currently considered, terms of the import permit require no genital
examination, no artificial insemination, and no breeding. The import
permit also stipulates extensive biosecurity requirements. The risk of
exposure of U.S. horses to CEM transplacentally is negligible. The
imported horses will not be entering the United States for breeding
purposes. The primary focus of the remainder of the assessment will be
exposure via breeding.

NCIE anticipates that between 1 and 10 performing groups varying in size
from 5 to 40 horses each (between 5 and 400 horses total) will utilize
this exception each year. These regulations will apply to the
importation of horses from countries recognized by the United States as
CEM-affected. A list of these countries can be found in 9 CFR 93.301 and
include: Austria, Belgium, Bosnia and Herzegovina, Croatia, Czech
Republic, Denmark, Finland, France, Germany, Guinea-Bissau, Ireland,
Italy, Japan, the Member States of the European Union (EU), The
Netherlands, Norway, Slovakia, Slovenia, Sweden, Switzerland, the Former
Yugoslav Republic of Macedonia, the United Kingdom (England, Northern
Ireland, Scotland, Wales, and the Isle of Man), and the nonrecognized
areas of the former Yugoslavia (Montenegro and Serbia).

The prevalence of CEM within this group of countries varies greatly
depending upon the availability and quality of veterinary services,
surveillance and control systems, and the practices of individual herds
within these countries. Certain countries within the EU consider
themselves CEM free. However, the United States considers all EU member
countries to be CEM-affected because of the lack of EU regulations
governing the movement of horses concerning CEM. (Federal Register: May
13, 1994)

Specific prevalence data is not readily available for most, if any, of
the countries listed as CEM-affected. Limited reports of results of CEM
testing are available through various resources. Each of these resources
has its own inherent problems, because of the limited scope of the
testing or limited sampling pool.

Summaries of some of the CEM testing data found are included below:

-   Testing statistics from 1 document produced by the French government
    found 19 positive animals out of 19,085 horses tested in 2003
    (0.1%). (AFSSA, 2003)

-   One study from Austria tested 139 clinically healthy Austrian
    Noriker draught horse stallions for CEM by culture and PCR. One
    stallion (0.7%) tested positive for CEM via PCR. All stallions were
    culture negative. (Stanek & Mache, 2003)

-   In the *Equine Quarterly Disease Surveillance Report,* issued for
    the first quarter of 2006 (DEFRA/AHT/BEVA), results of CEM samples
    submitted to the Veterinary Laboratories Agency in the UK were
    reported. This laboratory primarily conducts tests for international
    trade. No positive samples were found among the 1298 submitted for
    culture from 495 horses.

-   Between 1999 and 2001, 4 of 120 imported stallions (3.3%) tested
    positive for CEM at an import quarantine facility in Darlington, MD.
    The stallions were from Germany (2), Holland, and the Republic of
    Slovenia and consisted of two warmbloods, one thoroughbred and one
    Lipizzaner. (Kristula & Smith, 2004)

The likelihood that a horse imported from a CEM-affected country will be
carrying CEM cannot be estimated without prevalence data. For the
purposes of this analysis, it will be assumed that the imported horses
are CEM carriers. Pathways by which U.S. horses could become exposed and
infected will be examined.

## Exposure Assessment

Exposure assessment focuses on the biological pathway(s) identified in
the release assessment necessary for exposure of animals and/or humans
in an importing country to the hazards released from a given risk source
(OIE 2005a). This is followed by an estimate (qualitative or
quantitative) of the probability of the exposure(s) occurring.

All equids are susceptible to infection with CEMO. The risk of exposure
of imported horses to wild or zoo equids is negligible because of the
terms of the import permit as currently developed,. The risk of exposure
of imported horses to valuable breeding horses (such as Thoroughbreds)
is negligible, since isolation facilities are required to be
non-breeding premises. In addition, large, breeding equine facilities
tend to have high levels of biosecurity. (USDA 1998) The segment of the
horse population with the greatest possibility of exposure to the
imported horses are non breeding horses that might be present at
stabling facilities in the States visited by the performing troupes. In
the past, States visited have included: Arizona, California, Florida,
Georgia, Louisiana, Maryland, Massachusetts, Missouri, New York, North
Carolina, Ohio, Pennsylvania, Texas, Virginia, and Washington. The
mitigations in place including separation requirements, travel under
permit and seal, prohibition of travel to breeding premises, prohibition
of breeding or genital examination, approval of all destinations in
advance, and supervision by security, an accredited veterinarian, and
APHIS employees are sufficient to decrease the risk of exposure of
nonbreeding horses to an extremely low level.

The risk of exposure of U.S. horses to CEM via breeding with an imported
horse is extremely small, if there is compliance with the terms of the
import permit:

-   All sites visited by the imported horses are approved in advance by
    APHIS personnel to prevent exposure to other horses.

-   Imported horses are separated from other horses by an empty stall, a
    large empty area, or a solid wall at least 8 feet tall.

-   The use of sealed trailers (and the involvement of APHIS personnel
    in the procedure) for transportation makes it highly unlikely that
    an imported horse could breed a U.S. horse during transportation.

-   The horses are subject to a high level of supervision that includes
    24-hour security, daily monitoring by an accredited veterinarian,
    and frequent spot checks by APHIS personnel.

-   An APHIS Veterinary Medical Officer (VMO) that supervised performing
    troupes in the United States on the 90-day permits for competitive
    horses, observed excellent compliance with regulations. The VMO felt
    the risk that the imported horses would be exposed to U.S. horses
    was very low. (Personal communication)

-   Expert opinion concurs that the CEM temporary isolation facility
    separation and biosecurity requirements are sufficient to prevent
    venereal transmission of CEM. (Timoney, personal communication)

-   The participation of horses imported from CEM-affected countries in
    parades is unlikely to increase the risk of exposure of U.S. horses
    to CEM. It is possible that police horses could be present,
    depending on the location of the parade. Most police horses are
    geldings and pose no risk for transmission. A variety of horses
    could participate in the parades, but it is unlikely that
    circumstances at a parade would allow for breeding to occur.

-   As currently proposed, the requirements for isolation facilities do
    not address some situations that might arise during an extended
    importation. As the process of rules development proceeds, it will
    be vital to consider such situations. See the section *Further
    Considerations* for more information.

It is possible that an importer could intentionally choose to violate
the terms of the import permit in order to use the imported horse(s) for
breeding of domestic horses, particularly considering the high value of
some entertainment horses. This risk varies because of many factors
including motivation and ethics of the importers, location of the
horses, and value of the imported horses. The VMO who supervised two
different performance troupes found that compliance with requirements
was very good. The VMO did not feel they would be likely to try to
deviate from the requirements. (Personal communication, Lubamira Soroko,
USDA-APHIS-VS, 8/7/2006) The risk that importers would intentionally
violate the terms of the import permit is extremely low to negligible.

## Consequence Assessment

CEM is a disease notifiable to the OIE. It is highly contagious. If
breeding were to occur between an imported CEM carrier and a U.S. horse,
the risk that disease transmission would occur is very high. If CEM were
diagnosed in a domestic horse, whether a pleasure horse or a valuable
breeding animal, the United States would be required to immediately
notify the OIE of its change in status. It is likely that all exports of
live horses would be stopped until the United States could negotiate
regionalization or import and testing requirements. Additionally,
individual States could choose to stop interstate or intrastate movement
of horses, ban breeding within their State, or develop testing
requirements for breeding or movement of horses.

The previous outbreak of CEM that occurred in the United States was
recognized and confirmed quickly. The treating veterinarian immediately
suspected CEM and confirmed the diagnosis by culture within 72 hours.
(McGee, 1978) If recognition of CEM were to occur as quickly in the
event of a United States outbreak, it is unlikely that it will have
spread extensively. The incubation period for CEM is between 2 and 12
days. Since CEM primarily spreads via venereal contact, not casual
contact, it would not be likely to have spread to very many animals
prior to recognition.

The portion of the U.S. horse industry that would have the most severe
economic consequences if CEM were diagnosed in the United States would
be the breeding industry, such as the Thoroughbred horses of Kentucky.
If CEM were diagnosed in a breeding Thoroughbred, the economic
consequences would be devastating. If CEM were diagnosed in a pleasure
horse, the economic impacts to the equine breeding industry would be
much less severe. (Timoney, personal communication) In that case, the
United States most likely could negotiate some form of regionalization
or compartmentalization. Exports of breeding horses could still occur,
although horses likely would be required to undergo CEM testing.

With the mitigations as currently proposed, the risk of exposure of
imported horses to the Thoroughbred population is extremely small,
particularly considering the high level of biosecurity present at most
large horse breeding operations. (USDA 1998) The risk of exposure of the
imported horses to non-breeding pleasure horses is extremely small as
well, particularly considering the mitigations imposed by the import
permit.

## Risk Estimation

In order to assess the risk fully, it would be helpful to have accurate
prevalence data. If the importer complies with the terms as proposed,
the risk of exposure of breeding Thoroughbreds is negligible and the
risk of exposure of non-breeding pleasure horses is extremely low.
Therefore, the risk posed by allowing the extended importation of
noncompetitive entertainment horses from CEM affected countries is
extremely low, with the application of the restrictions described.

## Data Limitations

The quality of a risk assessment is limited by the availability of data
pertaining to its subject. The lack of data pertaining to the prevalence
of CEM in affected countries greatly limits this risk assessment. If
this data were to become available, then a more extensive risk analysis
could be conducted.

# TRACKING IMPORTED HORSES

The issue concerning the level of USDA supervision that is necessary in
order to insure that these horses are not lost to follow-up as they
travel from State to State is somewhat difficult to address. APHIS
supervises nearly everything that occurs while the horses are in the
United States. All movements occur under permit, all facilities are
inspected and approved prior to arrival, and spot checks are conducted
at least two times per week. The risk that the USDA will lose track of
these horses is extremely low because of good communication between the
Area Offices, field staff, and NCIE,

The quality of animal identification information provided on the import
permit and the nature of any methods of identification on the animals,
will greatly influence the ability of APHIS to track these individual
animals. Permits that merely contain a written description of the
horse's color, markings, sex and breed, create difficulty for APHIS to
verify the identity of each animal. Photographs or the presence of
permanent tamperproof identification such as brands, lip tattoos and
radio frequency identification devices (RFID) are more reliable forms of
identification, decreasing the ability of an importer to substitute or
divert animals.

Accurate electronic records with easy access for permit and animal
identification data is important when considering APHIS' ability to
track imported horses. Ensuring timely and accurate entry of permit data
as permits are issued and modified, will ease communication between the
field and NCIE staff. The National Animal Identification System (NAIS)
will be a useful resource for guidance as it is further developed and
implemented. .

# FURTHER CONSIDERATIONS

During an extended period of importation, situations may arise that are
not considered in the current regulations for competitive horses. A
troupe may utilize facilities for extended periods of rest or training.
Additionally, as entertainment, rather than competitive animals, some
troupes may desire to participate in exhibitions such as parades or
festivals. Some situations that will be considered as the rule making
process proceeds include:

-   Importers may want the ability to turn the imported animals out to
    pasture. Acceptable conditions for fencing and separation while at
    pasture are not contained in the current regulations.

-   Over an extended period, conditions within or around the approved
    isolation facilities could change. During APHIS spot checks, it will
    be important to watch for changing conditions, such as seasonal use
    of adjacent pastures or changes in the population of U.S. horses
    present at stabling facilities.

-   Approval for parades should be considered on a case-by-case basis,
    similar to the method for approval of isolation facilities. Approval
    could include obtaining information from the parade sponsor
    concerning parade conditions and other participating equines to help
    evaluate risks and develop necessary mitigations and separation
    requirements. If warranted, approval could also require notification
    of other equine participant concerning separation requirements.

The compliance agreement signed between APHIS and the importer could be
used to address some issues that will arise as the result of extended
importation. It could include statements clarifying required
communications, procedures to follow if importer desires to transfer
horse(s) to permanent entry, consequences for violation of the terms of
the import permit, and information concerning the role of the accredited
veterinarian, including the importer's role to retain and pay one.

Education of the accredited veterinarian concerning their expectations,
responsibilities, and liabilities as an accredited veterinarian and the
import requirements is one of the most important ways to mitigate risk
associated with the extended importation of horses from CEM-affected
countries. The accredited veterinarian is likely to be highly motivated
to prevent a violation of the import requirements, particularly if they
are aware of their personal liability as an accredited veterinarian. If
horses under an accredited veterinarian's supervision were to violate
the import requirements, the veterinarian's reputation and accredited
status would be at risk. The veterinary license issued by the State
could also be revoked in cases of severe misconduct. Loss of
accreditation status, or license to practice veterinary medicine, would
result in a large loss of clients and income.

# SUMMARY

A quantitative estimate of the risk that horses imported from
CEM-affected countries will have CEM is not possible to determine, as
reliable statistics concerning the prevalence of CEM are not available.
Although all equids are susceptible to CEM, the mitigations as currently
developed are sufficient to reduce the risk of exposure of all segments
of the U.S. equine population to an extremely low level. As rule making
proceeds, it will be important to address situations that arise because
of the extended time period that were not relevant to the rule for
competitive horses.

The risk that the USDA will lose track of these imported horses while in
country for extended periods is more difficult to characterize. However,
due to the extensive supervision and involvement of APHIS personnel and
the accredited veterinarian, the risk that the USDA will lose track of
these horses is extremely small. The use of a high quality individual
animal identification system along with good communication between the
importer, NCIE, APHIS field personnel, and the accredited veterinarian
will be important in maintaining control of these imported animals.

# BIBLIOGRAPHY

1.  Agence Francaise de Securite Sanitaire des Aliments (AFSSA). (2003)
    *Bulletin Epidemiologique*. 7: 1-6.

2.  Animal and Plant Health Inspection Service, United States Department
    of Agriculture, November 1999. Risk Assessment: Importation of the
    Pure Bred Horse of Spain.

3.  Anzi T, Wada R., Okuda T., & Aoki T. (2002) Evaluation of the field
    application of PCR in the eradication of contagious equine metritis
    from Japan. *J. Vet. Med. Sci.* 64(11): 999-1002.

4.  Aurich Ch., Spergser J., Nowotny N., Rosengarten R., & Aurich
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# APPENDICES

## Appendix 1: CEM Temporary Isolation Facility Checklist

![](media/image3.wmf){width="6.502777777777778in"
height="8.331944444444444in"}

![](media/image4.wmf){width="6.0in" height="8.415277777777778in"}

![](media/image5.wmf){width="6.0in" height="6.126388888888889in"}

## Appendix 2: Sample Compliance Agreement

![](media/image6.wmf){width="6.503472222222222in"
height="8.539583333333333in"}