A survey of canine echinococcosis in Gobi Altai Province of Mongolia by coproantigen detection.
ABSTRACT Few studies have been carried out for the prevalence of canine echinococcosis in Mongolia. This study was designed to elucidate a preliminary information of the prevalence from feces collected in the field. Sixty-seven fecal samples from dogs and 2 red foxes in Altai town were collected and examined for Echinococcus coproantigen and eggs. Coproantigen detection was performed by a sandwich ELISA using a monoclonal antibody EmA9 raised against Echinococcus multilocularis somatic antigen. Of the dog samples examined, 17 (25.4%) were positive by the ELISA. One out of two foxes was positive, too. Taeniid egg-positive feces were recognized in 12 dog feces. Only 6 samples were both coproantigen and egg positive. Eggs of Ancylostoma sp., Trichuris sp.; and Capillaria sp.; were also registered.
Instructions for use
A survey of canine echinococcosis in Gobi Altai Province of
Mongolia by coproantigen detection
ZOLJARGAL, Purevjav; GANZORIG, Sumiya; NONAKA,
Nariaki; OKU, Yuzaburo; KAMIYA, Masao
CitationJapanese Journal of Veterinary Research, 49(2): 125-129
Hokkaido University Collection of Scholarly and Academic Papers : HUSCAP
lpn. l. Vet. Res. 49 ( 2) : 125-129 (200l)
A survey of canine echinococcosis in Gobi Altai Province of Mongolia
by coproantigen detection
Purevjav ZoljargaP, Sumiya Ganzorig2, Nariaki Nonaka2,
Yuzaburo Oku2 and Masao Kamiya2
(Accepted for publication: August 10, 200l)
Few studies have been carried out for the prevalence of canine echinococ-
cosis in Mongolia. This study was designed to elucidate a preliminary infor-
mation of the prevalence from feces collected in the field. Sixty-seven fecal
samples from dogs and 2 red foxes in Altai town were collected and examined
for Echinococcus coproantigen and eggs. Coproantigen detection was per-
formed by a sandwich ELISA using a monoclonal antibody EmA9 raised
against Echinococcus multilocularis somatic antigen. Of the dog samples ex-
amined, 17 (25.4%) were positive by the ELISA. One out of two foxes was
positive, too. Taeniid egg-positive feces were recognized in 12 dog feces. Only 6
samples were both coproantigen and egg positive. Eggs of Ancylostoma sp.,
Trichuris sp., and Capillaria sp. ; were also registered.
Key words: coproantigen, echinococcosis, Mongolia
Echinococcosis that caused by Echinococ-
cus granulosus is of considerable economic
and public health importance in Mongolia.
Human cases have been registered in all
Provinces among both rural and urban resi-
s1• Wolves and dogs have been reported
as definitive hosts2.S) and the list of in termed i-
ate hosts included almost all the species of
wild and domestic ungulates in Mongolia13) •
An accurate diagnosis of E. granulosus
infection in the definitive hosts has always
been one of the most important components
[Department of Veterinary Medicine, Gobi Altai, Mongolia
"Laboratory of Parasitology, Graduate School of Veterinary Medicine, Hokkaido University
Dr. Masao Kamiya
Laboratory of Parasitology, Department of Disease Control, Graduate School of Veterinary Medicine,
Hokkaido University, Sapporo 060-0818, Japan
Survey on canine echinococcosis in Mongolia
for establishing epidemiological parameters of
this diseasell). However, very little compara-
tive work has been done on hydatid infection
in wild and domestic carnivores in Mongolia.
Existing reports on the prevalence in Mongo-
lia are based on the postmortem examination
of the stray dogs only3,5;. Diagnosis of echino-
coccosis in the definitive host through detec-
tion of the coproantigen has been recently
performed in some endemic countries.
Coproantigen detection corresponds to the
presence of worms in the intestine and is a
good tool for diagnosis of infected dogs1,4,sl.
Monoclonal antibody, EmA9, raised against E.
multilocularis adult worm somatic antigens
produced by Kohno et a1.8l has been reported
to be useful for the coproantigen detection of
E. granulosus 9,11) •
In this study we tried to elucidate a pre-
liminary information of the prevalence of ca-
nine echinococcosis from feces collected in a
rural town of Mongolia using the coproanti-
gen detection methodlOl• The study area is Al-
tai town of Gobi Altai Province, Mongolia.
The Province is situated in the south-west of
Mongolia, inhabited by 72,000 people and 2.1
million of livestock. The territory is 142,200
km", large part of which is covered by deserts
and mountains. The main activity of the rural
population is an animal husbandry. Altai
town is the center of the Province and has
population of 20,000.
Twenty seven fecal samples were col-
lected from 27 pet dogs and 40 fecal samples of
stray dogs were collected at the sites where
stray dogs were often observed in Altai town.
Two rectal feces of wild red foxes (Vulpes
vulpes) were also collected from the captured
foxes in the town. The samples were first ex-
amined on the presence of helminth eggs and
then were used for coproantigen detection by
(ELISA). All fecal samples were mixed with
1 % formalin solution in the collection vial
with screw cap and heated for at least 12
hours at 72° C. Each vial was weighed and fe-
cal weight was calculated. Parasite egg ex-
amination was conducted by the sucrose cen-
trifugal flotation technique with a sucrose so-
lution of specific gravity 1. 27.
coproantigen detection, fecal mixture was di-
luted to the final concentration ofO. 5 gram fe-
ces in a total volume of 15 ml 1 % formalin
containing 0.3% Tween 20. The sample was
then shaken vigorously by hand to form
slurry and centrifuged at 2000 g for 10 min-
utes at room temperature. The supernatant
was used for the coproantigen detection assay
and the sediment used for egg examination.
Coproantigen detection assay was performed
as described by Morishima et al.lO). A cut off
value to determine positive and negative was
calculated to be 0.179 which is the mean OD
value plus 3 S.D. of fox negative samples.
Results of the sandwich ELISA versus oc-
currence of taeniid eggs in 67 dog feces are
shown in Table 1. Seven out of 27 pet dogs
(25.9%) and 10 out of 40 (25.0%) stray dogs
examined were coproantigen positive. One
out of two samples from red foxes was positive.
The taeniid egg-positive feces were collected
from 12 dogs, including two from pet dogs and
10 from stray dogs. Of the 17 (25.4%) sam-
ples positive by the sandwich ELISA, only 6
Table 1. Comparison of coproantigen detec-
tion and taeniid egg examination of the dog
fecal samples in Altai town (Gobi Altai Prov-
ince, Mongolia) .
Purevjav Zozljargal et al.
were taeniid egg positive. Parasite eggs other
than those of taeniid cestodes found in dogs
included Ancylostoma sp., Trichuris sp., and
Capillaria sp. Because, the eggs of E. granu-
los us could not be distinguished fronl those of
other taeniid species, species identification
was not provided.
In this study we did not determine the
sensitivity and specificity of the sandwich
ELISA, because the present results were not
confirmed by postmortem examination of the
dogs. The mAb (EmA9) -based coproantigen
assay used in this study was reported to
scarcely cross-react with supernatants of fe-
ces collected from dogs and cats infected with
Taenia crassiceps and T.
spectively121, although Malgor et al.
that coproantigen of mature and patent T. hy-
datigena showed weak cross-reaction in the
assay used. In Mongolia, dogs are reported as
definitive hosts for E. granulosus, T. cras-
siceps, T. hydatigena, T. pisiformis, T. mul-
ticeps, T. gaigeri, T. serial is ,Dipylidium can-
inum, Toxascaris leonina and Macracan-
thorhynchus catulinus2,:lI. Therefore, probabil-
ity of cross-reaction with coproantigens of T.
hydatigena and other Taenia species should
be taken into consideration. Comparison of
the coproantigen detection with fec:al egg ex-
amination showed that only 6 samples were
positive by both methods. Of the taeniid egg
positive samples 6 were coproantigen nega-
tive, and eggs were not found from 11 coproan-
tigen positive fecal samples. The former may
indicate infection of taeniid species other than
Echinococcus or T. hydatigena. The latter
may indicate higher sensitivity of the
coproantigen detection assay than fecal ex-
amination of eggs. Of special interest here is
a positive sample from red fox.
foxes are rarely harbor E. granulosus , the
possibility of incidence with E. multilocularis
should be taken into consideration. To date, E.
multilocularis have not been reported in Mon-
ported 5-16.9% in stray dogs in Mongolia2,3,51.
Coproantigen prevalence (25.4%) in dogs in
the study area can be considered high. Estab-
lishments of private ownership of livestock
and abolition of the state run farms in Mongo-
lia largely affected veterinary services and in-
creased environmental pollution by invasive
agents. Due to lack of financial resources in
both state and newly established private en-
terprises, the state-ordered dehelminthization
program is not more implemented. To date,
only infectious disease control is being per-
formed. Repeated use of the pastures by the
growing number of livestock are not only
causing overgrazing but contamination by in-
vasive agents, too. Despite sharp increase of
livestock population the provincial slaughter-
houses and other small factories were closed;
animals slaughtered without any veterinary
control and dogs have ready access to offal.
Therefore, the prevalence of echinococcosis
might be considered much higher among
shepherd dogs. The current status of the echi-
nococcosis in the Province is not known. Only
3 patients were diagnosed with cystic echino-
coccosis and took surgery treatment. How-
ever, in the neighboring Province of Hovd and
Bayan Ulgii, serological prevalence of anti-
bodies against E. granulosus antigen B
among semi-nomadic pastoralist reported
5.2%11. Further studies are required to de-
termine the prevalence of echinococcosis in
both definitive and intermediate hosts.
• Prevalence of E. granulosus was re-
We would like to thank the staff of the Labo-
ratory of Parasitology, Graduate School of Vet-
erinary Medicine, Hokkaido University, for
their valuable help. We would like to thank
the Japan Veterinary Medical Association and
Mongolian Veterinary Medical Association for
Survey on canine echinococcosis in Mongolia
giving us an opportunity for our cooperative
study at the Laboratory of Parasitology of
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