Linda. Munson,2. Dane. Sanderlin,3 and. Max J. G. AppeI4. I Department of Biology, ..... Robson,. 1973). Sera were evaluated for parvovirus antibody. (CPV-2).
Journal
SEROSURVEY
FOR
DEMOGRAPHY Scott
Marusha
WILD
Creel,1
Linda
DISEASES
DOGS
Munson,2
:5:3 4 , 1997. pp. 523-532 Ds’ae Association 1997
Disea.ws, © \Si!dlift’
AND
IN TANZANIA Dane
Sanderlin,3
and
J. G. AppeI4
Department
I
VIRAL
OF AFRICAN Nancy
Creel,1,5
Max
SELECTED
of %‘:1dlzfe
of Biology,
5971 7-0346, 2 Department
Montana
USA of Pathology,
State
School
University,
Bozeman,
of Veterinary
Medicine,
Montana University
of Tennessee,
Tennessee 37901, USA 3 Viral and Rickettsial Zoonoses Branch, Centers for Disease Control, 1600 Atlanta, Georgia 30333, USA 4 James A. Baker Institute for Animal Health, College of Veterinary Medicine, Ithaca, New York 14853, USA 5 Corresponding author
Knoxville,
Clifton
Road,
Cornell
N.E.,
University,
are endangered, with only 3,000-5,000 remaining unusually vulnerable to viral diseases, particularly rabies and canine distemper (CDV). However, canine distemper has been confirmed by laboratory diagnosis in only one free-living wild dog. The 43,000 km2 Selous Game Reserve (SGR; Tanzania) holds approximately 900 adult wild dogs. In a study area of 2,600 km2, the population maintained high density (1 dog/20.5 km2) from 1991 to 1996. The population was stable, varying 18% below and 9% above the mean density over the 6-yr period. Serum samples (n 22) collected over 3 \T showed that most individuals were exposed to CDV (59%: 95% confidence interval 43-76% African
ABSTRACT:
the
in
wild.
seropositive)
and
seropositive no during
the
(mean
survival
inversely
study.
and
SE
to
93,
1996.
stable
data
words:
Key
20
show
n
the
638
SGR
all age
235).
=
wild
that
wild
54-81% CDV
=
for
healthy
African rabies,
in
± 6%,
demographically
parvovirus,
died
populations
adults:
These
and
that
exposure
other
CI
0-17%).
dog
92
and
classes
uals
populations, to
distemper,
in
to
habitat
(Fanshawe
et
Malcolm, and
Heerden
1986;
to
± 8%,
n
=
like
those
of
and
CPV.
conservation,
after
mean 127,
size
low 22
between
canids,
±
1992
can
remain
Lycaon
demography,
was
were
yearlings:
little
other
with
sampling
litter rates
fluctuated
were
age,
seroconverted
mortality
CDV
a!.,
the
dog
and
Creel et
al.,
Alexander
one
Goddard,
cribed
information
a single
National population 1970 and of
disease.
a fatal
illness
pack loss,
eyes,
most
from
pictus,
to canine attributed
in
the
Park (SNP, Tanzania). declined to extinction 1991, with recurrent Schaller among
that
staggering
on wild
population
caused
(1972) the
de-
members
anorexia
mucopurulent
ing. Based on these mortem examination tality in three packs
persecution
diseases
1995;
of weight
competition
(Estes 1979;
scribed
Creel
wild
recently,
came
outbreaks
low
and
limit
interspecific
Gascoyne
et
with
human
infectious
1991). largely
conditions
Creel may
and
is
all
1991;
carnivores
1996),
31 rates
Serengeti The SNP between
individ-
a!.,
combined
factors
1967; den,
a!.
1988), larger
et
under
including
(Childes,
5,000
are
(Ginsberg status
loss
Several
pictus)
Fanshawe
density
numbers,
to wild
precarious
population
with
the
1990;
due
1996).
3,000
with
species’
in
Annual
Until
(Lycaon
dogs
remaining
Macdonald,
none
related
serology.
wild
The
although
positively
Variation
mortality
exposure
canine
days,).
(pups:
dogs endangered,
were
elsewhere.
Annual
despite
dog,
±
INTRODUCTION African
seropositive),
titers
1.9 yr. At least five of 13 dogs positive for CDV CDV titers did not survive better in the years
high
those
CPV
95%
CI
than
for
to
(68%:
95%
with
Dogs
comparison n
parvovirus (0%:
younger
±
related
10%,
that
rabies dogs
(Lycaon pictus) wild dogs are
dogs
canine
for
seropositive
in
wild
It is believed
and
discharge
and
from
myoclona!
twitch-
clinical signs and of one carcass, in
1967-1968
distemper. a decline
postmor-
was
as-
Malcolm 197 1-1973
and
Creel,
(1979)
(van
Heer-
to disease, though no serological or postmortem data were collected to identify the pathogen (cf Burrows et a!., 1994). In the late 1980’s and early 1990’s, the last few
1993;
van
et
al.,
1996). 823
in
824
JOURNAL
wild
dogs
bies
OF WILDLIFE
in SNP
disappeared
epizootic.
was
DISEASES,
Rabies
confirmed
33, NO. 4, OCTOBER
during viral
in four
VOL.
a ra-
1994). graphic
encephalitis
cases
by
brain
his-
tology and which was in domestic
by isolation of the rabies virus, typed as a variant similar to that dogs neighboring the park
(Gascoyne
et
1997
18)
Combining data, van
concluded
that
incriminated death” these
serological Heerden “disease
as
an
in KNP. populations
It
could
important
not
be
cause
of
remains possible are vulnerable to
a!., 1993; Kat et a!., 1995). data from SNP have shown diseases can cause substan-
diseases,
tial
and
virus, CDV or parvovirus anthracis, the bacterium has caused several deaths
(CPV). Bacillus causing anthrax, in KNP, SGR,
and in Luangwa, 1991; Creel et
(Turnbull et van Heerden
mortality,
extinction. conviction
This that
sensitive 1991, “a
p.
main
has wild
to
disease”
140),
and
role
butional et a!., known
can
in
led to the widespread dogs are “particularly (Fanshawe that
the
et
disease
numerical
in
SNP
population
other
wild
(Frame eraging
played
and
distri-
,
intense
many
unusual
1979;
riod (data from 1994). Competition and
populations.
density
in
km2
over
a 20
av-
yr pe-
and
that
could
harbor
eared 1993),
foxes, domestic 1994),
me galot (Alexander
Otocyon
dogs
jackals,
Canis
(Alexander
mesornelas
is’
in with virus bat-
and
misleading
to generalize
about
population Despite
the
role
it
of disease
dynamics. close monitoring,
in wild
serve yr
of 22 yr. or in the (SGR, (Reich,
Tanzania) 1981;
the
ever
dog
other
over Maddock
Game a period and
a
Reof 6 Mills,
CPV dogs,
are
exposed
but
a!., 1994). shown to may
(Mech
hinder
and
carcasses impossible
Goyal
of wild dog to collect, it
No data exist to establish is caused by CPV. wild
unvaccinated
to have nor been
antibodies has canine isolated
dog
what
pro-
has
been
to CDV distemper from
(but
this
see virus
species.
Nonetheless, population declines have been attributed to CDV on the basis of behavioral observations (Schaller, 1972; Malcolm 1979) or concurrent outbreaks in
disease-relat-
Selous
that wild
et been
declines,
Because are virtually
No
be
Kruger over
1989; Johnston CPV has not a decline
found results),
from
ed declines were not observed in National Park (KNP, South Africa) period
may
al., et
is plausible that some juvenile mortality is due to undetected CPV, among other factors. Pup mortality can be substantial for wild dogs, with as high as 70% annual mortality in KNP (van Heerden et a!.,
C.
(Roel-
conclusions
to rabies
evidence
in free-living populations
after
1995).
CroHaas
leo
Zambia 1995;
direct
population
portion
Roelke-
Parker et a!., 1996), spotted hyenas, cuta crocuta (Alexander et a!., 1995; et a!., 1996), and lions, Panthera ke-Parker et a!., 1996). Thus,
1993). pups
(Maas, and Ap-
1994,
no
In
screening
et al.,
recovery
and
aureus
et a!.,
is
exposed.
of exposure
a!.,
mortality some
cause
Fitzgibbon,
might have limited wild dog (Creel and Creel, 1996). Finally,
carnivores
causes although
evidence
Krumenaker, For wolves,
sources in Burrows et a!., from larger carnivores
(Fanshawe
1995). There
been
serological
1992), and it is reasonable to hypothesize that CPV is a factor in some pup deaths. CPV can cause substantial mortality in young wolves (Peterson and
low
1979),
no
(Fuller
several
very
transmit viral infections were common the SNP ecosystem. Common species known exposure to canine distemper (CDV) and/or rabies virus included
SNP
a!.,
The
was
Malcolm,
1 dog/200
