Download Organization of wildlife disease services in the United States

Rev. sci. tech. Off. int. Epiz.,
1988, 7 (4), 797-805.
Organization of wildlife disease services
in the United States
J.W. GLOSSER * and V.F. NETTLES **
Summary: Wildlife disease services in the United States are provided by a broad
network of organizations that include state and Federal fish and wildlife agencies,
public health agencies, and agricultural agencies. These agencies collaborate
with each other and with universities and other entities. A relationship which
has considerably advanced animal health in the United States involves the
collaboration of the US Department of Agriculture (USDA) and the
Southeastern Cooperative Wildlife Disease Study (SCWDS).
KEYWORDS: Disease control - Governmental agencies - Research - USA - Wild
animals.
INTRODUCTION
A recent survey by the US Department of the Interior (USDI) revealed that wildlifeassociated recreation accounts for the spending of $55.4 billion annually in the United
States (18). Each year, one of every two adult Americans participates in some form
of outdoor activity involving fish and wildlife, making wildlife enjoyment the leading
sports activity in the nation. T h e importance of wildlife to American citizens has
resulted in a b r o a d range of interests for maintaining its well-being.
P r i m a r y responsibility for the health of wildlife in the United States resides with
the USDI's Fish and Wildlife Service (USFWS) and with the fish and wildlife agencies
in the individual states. However, diseases of wildlife can directly affect the health
of h u m a n s and domestic animals, so Federal and state public health organizations
and agricultural agencies are engaged in wildlife disease research, diagnostic
investigations, epidemiological studies, and control programs. In all, there are three
Federal agencies and more t h a n 150 state or territorial fish and wildlife agencies,
agricultural agencies and also public health agencies which carry out activities related
to wildlife diseases. M a n y efforts are collaborative and may include scientists from
universities, zoological facilities, and even the U S Armed Forces.
The breadth of this interest is illustrated by noting the origin of recent articles
on wildlife disease in a sample of popular scientific journals (Table I). Most articles
were collaborative efforts a m o n g two or three groups. This paper outlines the
organization of this vast network of interests and provides information on the
* Administrator, Animal and Plant Health Inspection Service, United States Department of
Agriculture, Washington, D . C . 20250, U S A .
** Director, Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine,
University of Georgia, Athens, G A 30602, U S A .
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TABLE I
Sources of recent fish and wildlife disease information
pertaining to Lists A and B of the OIE
as obtained from a sampling of scientific journals* in the USA
(1983-1988)
Source
USDA
National Veterinary Services
Laboratories and/or
APHIS Field Personnel
Southeastern Cooperative
Wildlife Disease Study
Animal Disease Research Unit
Animal Parasite Institute
Arthropod-borne Animal
Disease Center
National Animal Disease
Center
Plum Island Animal Disease
Center
Southeast Poultry Disease
Research Laboratory
USDI
National Wildlife Health
Research Center
Patuxent Wildlife Research
Center
Cooperative Fish and
Wildlife Research Units
National Fish Health
Research Center
USDHHS
Centers for Disease Control
State fish and wildlife agencies
(states given in parenthesis)
Disease topic
African swine fever, brucellosis, leptospirosis,
Newcastle disease, porcine brucellosis,
Pseudorabies, rabies, tuberculosis, vesicular stomatitis
Bluetongue, brucellosis, fowl cholera, fowl pox,
infectious bovine rhinotracheitis, leptospirosis,
mycoplasmosis, porcine brucellosis, Pseudorabies,
trichinellosis, vesicular stomatitis
Anaplasmosis, babesiosis
Trichinellosis
Anaplasmosis, bluetongue, vesicular stomatitis
Brucellosis, fowl cholera, infectious bovine
rhinotracheitis, leptospirosis
Foot and mouth disease, heartwater
Mycoplasmosis
Avian tuberculosis, duck virus enteritis, fowl
cholera, fowl pox
Equine encephalomyelitis
Brucellosis, fowl cholera, infectious pancreatic
necrosis virus, yersiniosis
Infectious hematopoietic necrosis, pseudomonosis,
renibacteriosis, viral hemorrhagic septicemia, yersiniosis
Fowl cholera, rabies, vesicular stomatitis
Anaplasmosis (AK, NE), bluetongue (AK, CA, KY, NE,
OK, WY), brucellosis (AK, AR, CA, MN, MO, NE),
dermatophilosis (WY), duck virus enteritis (CA), equine
rhinopneumonitis (CA), fowl cholera (IL), fowl pox
(CA, OR), infectious bovine rhinotracheitis (AK,
CA, MN), leptospirosis (AK, AZ, CA, MN),
* American Journal of Veterinary Research, American Journal of Public Health, A vian Diseases, Journal
of the American Veterinary Medical Association, Journal of Parasitology, Journal of Wildlife Management,
Journal of Wildlife Diseases, Proceedings of the United States Animal Health Association, Wildlife Society
Bulletin.
799
TABLE I
Source
(contd.)
Disease topic
malignant catarrhal fever (CA, WY), mycoplasmosis
(CA), Pseudorabies (AZ), pulmonary adenomatosis
(CA), Q fever (AK, CA), rabies (AK), renibacteriosis
(NY), trichinellosis (AZ, PA), tularemia (AK),
vesicular stomatitis (AZ, CA, CO, WY), visna/maedi
(AK)
State agricultural agencies
Anaplasmosis (WA), anthrax (CO), bluetongue (GA,
WA), brucellosis (CA, GA, OK), equine
encephalomyelitis (NJ), infectious bovine
rhinotracheitis (GA, WA), leptospirosis (GA, WA),
malignant catarrhal fever (OK, WY), mycoplasmosis
(CA), trichinellosis (IL), tuberculosis (CO, SD),
vesicular stomatitis (WY), visna/maedi (WA),
yersiniosis (IL)
State public health agencies
Universities
Johne's disease (OH), rabies (CA, KY, NY)
Anaplasmosis (ID, NE, WA), anthrax (CO), avian
tuberculosis (IA), bluetongue (AL, CA, CO, FL,
GA, KY, NE, OK, TX, WA, WY), brucellosis (AL,
CA, MO, NE, OK), dermatophilosis (WY), duck
virus enteritis (CA, WI), equine rhinopneumonitis
(NY), fowl cholera (CA, MN, WY), fowl pox (KY,
OR), fowl typhoid (WI), heartwater (CA), infectious
bovine rhinotracheitis (KY, OH, OR, WA),
infectious pancreatic necrosis virus (FL, MD),
Johne's disease (CO, CT, OH), leptospirosis (AK,
AR, CA, MD, OH, OK, OR, TN, WA), malignant
catarrhal fever (OK), mycoplasmosis (CA, WI),
myxobolosis (PA), Newcastle disease (WI),
Pseudorabies (IA, TN), psittacosis (CA, ID, TX),
rabies (CA, TN), trichinellosis (CA, GA, IA, PA,
TX), tuberculosis (CO, IA), tularemia (AR, TN),
visna/maedi (WA), yersiniosis (GA)
Others
Bluetongue, brucellosis, equine encephalomyelitis,
equine rhinopneumonitis, infectious bovine
rhinotracheitis, leptospirosis, malignant catarrhal
fever, rabies, tularemia
cooperative relationship between the United States Department of Agriculture (USDA)
and the Southeastern Cooperative Wildlife Disease Study (SCWDS), an effort that
has greatly enhanced animal health in the United States.
W I L D L I F E D I S E A S E A C T I V I T I E S IN T H E F I S H A N D W I L D L I F E A G E N C I E S
T h e U S F W S has several laboratories which investigate fish and wildlife diseases.
These laboratories place special emphasis o n the health of migratory birds and
endangered wildlife species, since these animals are the major regulatory responsibility
of the U S F W S .
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The National Wildlife Health Research Center ( N W H R C ) , Madison, Wisconsin,
is a focal point for investigating diseases of waterfowl and endangered mammals and
birds, particularly in relation to large-scale die-offs (13). Most of the N W H R C ' s work
is directed toward national wildlife refuges where high concentrations of waterfowl
intensify disease problems. This laboratory also has the capability of working with
resident wildlife. In addition, services to other Federal agencies, state fish and wildlife
agencies, and private landowners are available u p o n request.
The U S F W S operates the Patuxent Wildlife Research Center, a large research
facility at Laurel, Maryland, where reproductive studies are conducted t o enhance
and replenish endangered species. This laboratory is the leader in studying how wildlife
is affected by pesticides, herbicides, heavy metals, and other pollutants. The Center
performs work that is national in scope and has several field stations located in other
areas of the nation.
The National Fish Health Center, Leetown, West Virginia, also is under the
auspices of the U S F W S . This laboratory is engaged in diagnostic work and research
on a variety of fish diseases and parasites, with special emphasis on the diseases and
parasites of a n a d r o m o u s and cold-water fishes.
Unfortunately, these agencies cannot fund wildlife disease research and
investigation capabilities on the scale needed. To utilize limited resources efficiently,
a cooperative approach has thus been developed. The two most successful of these
cooperative projects have been the S C W D S at the University of Georgia and the
Southeastern Cooperative Fish Disease Study at A u b u r n University in A l a b a m a .
Another state cooperative project is the Northeastern Research Center for Wildlife
Diseases at the University of Connecticut at Storrs.
Some state fish and wildlife agencies have disease investigation laboratories, staff
veterinarians, or both. Alaska, California, Florida, Michigan, N o r t h D a k o t a , and
Wyoming employ veterinarians, and several other states have disease specialists. Other
state fish and wildlife agencies rely on formal or informal relationships with
universities, state diagnostic laboratories, and various sources in the medical
community to help handle their disease problems. M u c h of the current knowledge
of wildlife and fish diseases has been acquired through the initiative of state wildlife
and fish biologists who have collaborated with other animal health experts when
diseases were encountered.
W I L D L I F E D I S E A S E A C T I V I T I E S IN P U B L I C H E A L T H A G E N C I E S
Public health authorities become involved with wildlife disease activities because
of such zoonoses as rabies, tularemia, sylvatic plague, Rocky M o u n t a i n spotted fever
(RMSF), brucellosis, arboviral encephalitides, leptospirosis, Lyme disease, and
trichinellosis. The interest of public health agencies is manifest primarily in diagnostics
and epidemiology of wildlife diseases. At the Federal level, the US Department of
Health and H u m a n Services ( U S D H H S ) maintains specialized disease laboratories
and epidemiologists at the Centers for Disease Control (CDC), Atlanta, Georgia.
When unexplained illness occurs in h u m a n s , the C D C can quickly mobilize a team
of experts to conduct a field investigation to examine any possible role that wildlife
may play in the disease. Such epidemiological studies usually are performed in
collaboration with the state public health and the state and Federal fish and wildlife
authorities.
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State public health agencies also study wildlife diseases that affect the h u m a n
population and often provide laboratory tests for the most notable zoonoses (rabies,
tularemia, plague, and R M S F ) . These agencies occasionally conduct field projects
such as the current rabies control research project being carried out by the Maryland
Department of Health and Mental Hygiene. In this project, raccoons are being trapped
and hand-vaccinated in a n 8.3 x 33.3 k m zone to stop the spread of rabies into the
Delmarva Peninsula.
2
W I L D L I F E D I S E A S E A C T I V I T I E S IN A G R I C U L T U R A L A G E N C I E S
Just as efforts to control h u m a n diseases may depend o n knowledge of wildlife
diseases, so efforts to protect the health of livestock and poultry frequently require
extensive knowledge of wildlife disease. State and Federal agricultural officials
recognize that success or failure of livestock and poultry disease control or eradication
programs may depend u p o n the occurrence of such diseases in wild animals either
as principal, reservoir, or amplifying hosts.
Knowledge of the role of wildlife in disease transmission is especially critical when
exotic animal diseases are introduced and eradication is contemplated. T h e U S D A ' s
Animal and Plant Health Inspection Service (APHIS) has made substantial
preparation to address wildlife concerns if a foreign animal disease is introduced.
A P H I S maintains formal agreements to cooperate with Federal and state fish and
wildlife agencies in wildlife disease investigations. A P H I S has also incorporated
wildlife expertise into the organizational structure of its Regional Emergency Animal
Disease Eradication Organization ( R E A D E O ) .
The U S D A is involved in many other ways with wildlife disease research and
diagnostic investigations. U S D A laboratories such as the National Veterinary Services
Laboratories, the National Animal Disease Center, the P l u m Island Animal Disease
Center, the A r t h r o p o d - b o r n e Animal Diseases Research Center, the US Livestock
Insects L a b o r a t o r y , and others all provide specialized services and evaluate certain
aspects of diseases in wildlife.
Epidemiologists within U S D A often include wildlife in their investigations of
domestic animal diseases, and the U S D A may fund wildlife disease research with other
organizations. Some examples of special projects are studies which examined
brucellosis in elk (Cervus canadensis) and bison (Bison bison). These studies,
conducted in conjunction with the Wyoming Department of G a m e and Fish and with
Texas A & M University, showed that elk and bison can maintain Brucella abortus
and transmit the disease to cattle (2, 17). Studies on the efficacy of remote vaccination
of elk and bison with pelleted B. abortus vaccine are currently being evaluated. In
another study, the U S D A is cooperating with the San Diego Z o o in surveillance of
exotic wildlife in zoos for malignant catarrhal fever (8).
State agricultural agencies share concerns about the potential impacts of wildlife
disease on animal health p r o g r a m s . These agencies generally do not have specialized
units or organizations to work with wildlife diseases, but they contribute greatly to
the wildlife disease investigational network t h r o u g h their state veterinary diagnostic
laboratories. Frequently, the index case of a wildlife morbidity or mortality incident
is diagnosed by personnel at state agricultural agencies. Additional contributions
provided by these agencies include serological testing of samples from wildlife and,
802
in many instances, assistance in the development of microbiological and toxicological
tests for use in surveys of wildlife populations.
COOPERATION BETWEEN APHIS AND T H E SCWDS
The beneficial interaction of agricultural agencies and wildlife-oriented entities
is best illustrated by the long-standing cooperative relationship between the U S D A ' s
A P H I S and the S C W D S . A n early illustration of the benefits of this relationship
occurred during an outbreak of viscerotropic velogenic Newcastle disease (VVND)
in California, Florida, and Texas in 1971-1973. After a national emergency was
declared, a controversy ensued concerning the assumption that V V N D had become
established in free-flying birds, thus making control or eradication impossible. In
response to opposition to ongoing poultry depopulation, arrangements were made
to cooperate with SCWDS in assessing free-flying bird involvement. Laboratory tests
showed t h a t wild birds were neither reservoirs nor disseminators of the disease and
that eradication could be accomplished.
In 1978, A P H I S entered into a cooperative agreement with SCWDS for the purpose
of integrating wildlife disease surveillance capabilities into established domestic animal
health programs (7). This long-standing agreement represents an unprecedented merger
of domestic livestock and wildlife interests and is focused on achieving the following
objectives:
1. to determine the interrelationships of transmissible diseases between wild and
domestic animals;
2. to assist A P H I S in surveillance for foreign animal diseases;
3. to serve A P H I S in an advisory capacity on wildlife management and its
relationship to diseases of domestic animals;
4. to act as liaison among state, Federal, and private sectors responsible for the
health of the nation's domestic livestock, poultry, and wildlife resources.
Through the A P H I S / S C W D S cooperative agreement, the U S D A has gained much
information about the relationship of diseases of domestic animals and wildlife. For
example, national surveillance of wild swine (Sus scrofa) revealed that some
populations are infected with Brucella suis ( 1 , 20) and Pseudorabies (10), but hog
cholera virus is not residual in wild swine. Surveillance of wild swine and axis deer
(Axis axis) conducted in conjunction with Mycobacterium
bovis eradication from
cattle in Hawaii revealed that tuberculosis could be contracted by association with
infected cattle (3). Once infected cattle were removed from the range, however,
maintenance of M. bovis infections in wild swine and axis deer was not evident.
Some other topics addressed by A P H I S and S C W D S included the survey of
remnant wild swine populations in Haiti as possible reservoirs for African swine fever;
the epidemiology of vesicular stomatitis in an enzootic focus on Ossabaw Island,
Georgia (4, 14, 15, 16); a survey of wild mammals as a possible source of the cattle
fever tick along the Texas/Mexico border (5, 6); a survey of free-flying psittacine
and native birds as a potential source of recent VVND outbreaks in California, Florida,
and Hawaii; an assessment of small rodents and birds as possible sources of
Salmonella, Pasteurella, and Mycoplasma infections around poultry farms; and the
development of a model for state regulations pertaining to captive wild and exotic
animals.
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The A P H I S / S C W D S relationship has proven especially helpful in preparation
for emergency outbreaks. More than 90 Foreign Animal Disease Diagnosticians have
been trained in S C W D S seminars o n wildlife biology and c o m m o n native diseases
of wildlife. M a p s depicting the geographic distribution and estimated population
density of all native wild ungulates that would be susceptible to foot and m o u t h
disease, rinderpest, heartwater, and other diseases were prepared in 1982 and are being
updated.
During the outbreak of lethal H 5 N 2 avian influenza in 1983-1984 in Pennsylvania,
Virginia, Maryland, and New Jersey, the S C W D S and researchers at St. J u d e
Children's Research Hospital tested free-flying birds associated with infected poultry
in the quarantine zone and found that the lethal H 5 N 2 strain was not being
disseminated from farm to farm by wild birds. The survey also showed that waterfowl
were not serving as a latent reservoir for this m u t a n t strain even though waterfowl
harbored other forms of avian influenza virus (9, 11, 12, 19). These facts were
important in convincing poultry growers that eradication was a feasible goal and that
vigorous precautions by personnel were essential in stopping virus spread.
The relationship of A P H I S and the S C W D S has greatly advanced the knowledge
of animal health in the United States and illustrates the recognition of c o m m o n
interests which characterizes the US approach to wildlife disease services. The extensive
network of entities involved in wildlife disease services brings a broad range of expertise
to bear on the subject a n d , working collaboratively, these entities have rapidly
advanced knowledge on fish and wildlife diseases within the United States and should
continue to d o so in years to come.
ORGANISATION DES SERVICES SANITAIRES RESPONSABLES DE LA FAUNE
SAUVAGE AUX ÉTATS-UNIS. - J.W. Glosser et V.F. Nettles.
Résumé : Aux Etats-Unis, les problèmes sanitaires de la faune sauvage sont
pris en charge par un vaste réseau d'administrations parmi lesquelles figurent,
au niveau des Etats et au niveau fédéral, les services responsables des poissons
et de la faune sauvage, de la santé publique et de l'agriculture. Ces administrations collaborent entre elles ainsi qu 'avec les universités et d'autres institutions.
La santé animale a fait des progrès considérables aux Etats-Unis, notamment
grâce à la relation de collaboration active entre le Département de l'Agriculture
des Etats-Unis (USDA) et la Section d'étude en coopération sur les maladies
de la faune sauvage dans le Sud-Est («Southeastern Cooperative Wildlife Disease
Study», SCWDS).
MOTS-CLÉS : Administrations publiques - Animaux sauvages - Etats-Unis Prophylaxie - Recherche.
*
804
ORGANIZACIÓN DE LOS SERVICIOS SANITARIOS RESPONSABLES DE LA FAUNA
SALVAJE EN LOS ESTADOS UNIDOS. - J.W. Glosser y V.F. Nettles.
Resumen: En los Estados Unidos, los problemas sanitarios de la fauna salvaje
están a cargo de una amplia red de administraciones entre las que figuran los
servicios estatales y federales responsables de los peces y la fauna salvaje, salud
pública y agricultura. Estas administraciones colaboran no solo entre ellas, sino
también con las universidades y con otras instituciones. La sanidad animal ha
realizado considerables progresos en los Estados Unidos, gracias sobre todo
a la relación de colaboración activa entre el Departamento de Agricultura de
los Estados Unidos (USDA) y la División de estudios en cooperación sobre las
enfermedades de la fauna salvaje en el Sudeste («Southeastern Cooperative
Wildlife Disease Study», SCWDS).
PALABRAS CLAVE: Administraciones públicas - Animales salvajes Control - Estados Unidos - Investigación.
*
* *
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