Introduction
Echinococcus granulosus is an
important helminth of dogs that causes cystic echinococcosis (CE) in humans and
livestock. CE is an emerging and potentially avertable zoonotic disease of
veterinary and public health importance spreading into echinococcosis-free
regions of the world (Benito and Carmena 2005; Lahmar et al. 2007; Rossi
et al. 2012). It has been reported that CE affects at least one million
people across the world putting annual economic loss at about 3 billion US
dollars in terms of human treatment and losses in livestock production through
organ condemnation, carcass weight loss, decreased milk production, and poor
fecundity rate (Rashid et al. 2018). This burden is likely to be an
underestimation due to poor investigations and surveillance systems in some
endemic countries (WHO 2015; Dakkak et al. 2017).
E. granulosus is an
obligate endoparasite with an indirect type of life cycle involving two
mammalian hosts. Both domestic and feral dogs serve as definitive hosts that
harbor the adult tapeworm in their small intestine, releasing into the
environment (via feces) eggs
containing infective oncosphere, leading to the contamination of pastures (Acosta-Jamett et al. 2010). Viable eggs
in the environment can survive for a long period, thus increasing the risk of
exposure and chances of infection among intermediate hosts (domestic herbivores
and wild ungulates) including humans (Hidalgo et al. 2019). After ingestion of eggs, the onchosphere develops into
the larva stage metacestode (Thapa et al. 2017; Ingole et al.
2018; Mulinge et al. 2018).
Echinococcus infection in
dogs has been reported in many Asian countries including those sharing borders
with Pakistan like China, Iran, and India (Zhang et al. 2006; Ghabdian et
al. 2017; Thapa et al. 2017). To the best of our knowledge, no study
on the prevalence of echinococcosis in dogs has been conducted in Pakistan.
Thus, this study was designed to assess the prevalence of E. granulosus and the
risk factors associated with the infection in dogs.
Materials and
Methods
Study area
Three cities viz.,
Faisalabad, Islamabad, and Lahore were selected for this study (Fig. 1).
Geographical quadrants (latitudes and longitudes) of the study districts are
mentioned in Table 1 (Pakistan Meteorological Department 2019). Outdoor Patient
Departments of the Veterinary Teaching Hospitals of the University of
Agriculture, Faisalabad, the University of Veterinary and Animal Sciences,
Lahore and private pet clinics located in Islamabad were visited for sample
collection.
Sample collection
Fecal samples were collected from owned dogs brought to
the above-mentioned teaching hospitals and clinics through their owners who
were requested to bring fresh feces to the Teaching Hospitals/pet clinics on
their next visit, and also from feral dogs captured and brought to the same
hospitals for experimental purposes. A total of 368 (owned-dogs n = 296, stray/feral dogs n = 72) fecal samples were collected.
Each sample weighed approximately 25 grams. Owners were requested to put fecal
samples in phosphate-buffered saline. Samples were then transported to the
Laboratory of Department of Clinical Medicine and Surgery, University of
Agriculture, Faisalabad, Pakistan, where the samples were stored at
−80°C for a minimum of 5 days before testing (Liu et al.
2015; WHO/OIE 2001).
Risk factors investigation
Dog owners were also requested to complete a
questionnaire containing the following information: age of dogs (< 3 years
and ≥ 3 years), sex of dog (male and female), breed, feed type (raw meat,
leftovers from owner’s kitchen, or commercial dog feed), purpose (pet or guard)
and deworming status (yes or no). Body condition scoring was determined as described
previously (Baldwin et al. 2010).
The age of stray/feral dogs was determined by dentition
(Anonymous 1996) and the dogs were considered not to have undergone any
deworming treatment. Regarding feed type, data from the stray dog population
were not included in the analysis as we were unaware of their feeding pattern
(whether animal offal or disposed kitchen waste).
Copro-antigenic ELISA
All fecal samples were subjected to copro-antigenic
sandwich ELISA kit purchased from Zhuhai Haitai Biological Pharmaceuticals Co.,
Ltd., Zuhai, China having good sensitivity, specificity, and substantial kappa
value (Wang et al. 2021).
Briefly, the antigen was separated from each fecal
sample by mixing 1g of feces with 1 mL of the sample treatment solution and
centrifuged at 4000 rpm for 15 min. The sample supernatant was carefully
pipetted and stored in a 1.5 mL tube to avoid contamination from other fecal
materials. Two wells in the ELISA plate precoated with E. granulosus-specific
antibody were designated for positive and negative control samples and 100 µL
of controls was dispensed into those wells. In the test wells, 80 µL of
sample diluent and 20 µL of each sample were dispensed (except negative
and positive control wells). After incubation at 37oC for 30 min,
the plate was washed four times with 300 µL of washing solution (0.05%
PBS-Tween 20) according to the manufacturer's instruction. Afterward, 100 µL
of enzyme working solution (anti-E.g. specific
antibodies conjugated with horseradish peroxidase-HRP) was dispensed in each
well and incubated again at 37oC for 30 min followed by washing. Thereafter, 100 µL of
Chromogen-A and Chromogen-B (provided in the kit with 3,39,5,59-
tetramethylbenzidine, TMB) were dispensed in each well. The reaction was
allowed to stand for 10 min at 37oC. Finally, 50 µL of stop solution was added and the plate was
read within 5 min in a Bio-Rad
microplate reader (iMarkTMMicroplate Absorbance Reader). Optical density (OD) was measured at 450 nm.
Test validation
The test was
validated if the mean OD of negative and positive controls was less than 0.5
and greater than 0.8, respectively. The samples with OD ≥ critical value
(CV = mean OD negative control × 2.1) were considered positive while those with OD <
CV were negative.
Statistical analysis
Table
1: Geographical quadrants of study areas
|
City |
Quadrants |
|
|
Latitudes |
Longitudes |
|
|
Faisalabad |
31ş26’ |
73ş08’ |
|
Rawalpindi / Islamabad |
33ş68’ |
73ş04’ |
|
Lahore |
31ş35’ |
74ş24’ |
Table 2: Prevalence of E.
granulosus
in dogs sampled from three districts of Punjab province, Pakistan
|
District |
Positive/Tested |
Prevalence (95% CI) |
OR (95% CI) |
Statistics |
|
Lahore |
5/51 |
9.80 (4.26-20.97) |
1.95 (0.63-6.03) |
χ2 = 1.66 P-value= 0.435 |
|
Islamabad |
11/138 |
7.97 (4.51-13.71) |
1.23 (0.41-3.68) |
|
|
Faisalabad |
9/179 |
5.02 (2.67-9.28) |
- |
|
|
Total |
25/368 |
6.79 (4.64-9.83) |
|
|
CI
confidence interval; OR odds ratio
%20881-887_files/image002.png)
Fig. 1: Map of Pakistan. Sampling areas chosen for
collection of dogs’ fecal samples in this study are zoomed-in
Prevalence was estimated at 95% confidence interval (CI)
(Newcombe 1998). Chi-square test (χ2-test) was used to perform
test of significance between variables and results were significant at P < 0.05. Univariable analysis and
odds ratios (OR) were also carried out. Finally, a binary logistic regression analysis was
conducted to assess the association between copro-prevalence of E. granulosus and the
significant variables at the initial screening. All tests were carried out in
IBM S.P.S.S. Statistics 17.0 for Windows® (IBM Corporation, Route 100 Somers,
New York, U.S.A.).
Results
The overall copro-prevalence of E. granulosus in dogs’ feces was 6.79% in the understudied areas.
The highest copro-prevalence was recorded in Lahore (9.80%) followed by the
twin cities Islamabad/Rawalpindi (7.97%) and Faisalabad (5.02%) (Table 2).
According to dog sex, females were more copro-positive
(8.72%; 95% CI 5.36–13.89) than males (5.10%; 95% CI 2.79–9.13). Dogs ≤ 3
years of age were more copro-positive (6.93%; 95% CI 4.48–10.57) than those > 3 years (6.38%; 95% CI 2.96–13.23). Dogs without de-worming
history were found to be more copro-positive (8.98%; 95% CI 5.61–14.1) compared
to those with a history of anthelmintic treatment (4.73%; 95% CI 2.51–8.76).
Regarding dog captivity status, higher prevalence was
found in feral/stray dogs (9.72%; 95% CI 4.79–18.73) compared to
domestic/captive dogs (6.08%; 95% CI 3.88–9.41). Furthermore, companion dogs
fed with raw meat demonstrated higher prevalence (8.28%) than those fed with
commercially available/non-fleshy items (rice or bread). Unfortunately, the
feeding status of stray/feral dogs was undefined and thus not included in the
current findings. Dogs falling in Body Condition Score (BCS) in class 1–3
showed higher prevalence (10.86%; 95% CI 7.06–16.34) than those in class 4–6
(3.57%; 95% CI 1.53–8.09) and 7–9 (1.89%; 95% CI 0.33–9.95). Also, dogs with
apparent lower intestinal clinical diseases were more copro-positive (10.22%;
95% CI 6.64–15.41) for E. granulosus compared to healthy dogs
which showed only 3.33% copro-positivity.
In this study, copro-prevalence variation in relation to
dog breeds (13 different breeds) was observed as follows: Grey Hound (15.62%;
95% CI 6.87–31.76), Bulldog (10.00%; 95% CI 3.96–23.05), stray/feral (9.72%;
95% CI 4.79–18.73), Alsatian (8.33%; 95% CI 1.49–35.38), Bull Terrier (8.00%;
95% CI 2.22–24.97), German Shepherd (5.66%; 95% CI 1.94–15.37), Labrador
(5.00%; 95% CI 1.38–16.50) and owned non-descript (4.00%; 95% CI 1.1–13.46)
dogs. None of the dogs from Siberian Husky, Doberman, Cocker Spaniel,
Rottweiler, and Shih Tzu breed was found positive.
Univariate analysis
(Table 3) of the study variables revealed that dogs age ≤ 3 (OR 1.06),
female (OR 1.71), stray/feral dogs (OR 1.60), dogs fed with raw meat (OR 2.63),
BCS 1–3 (OR 5.75), dogs with intestinal illness (OR 3.06), Grey Hound breed (OR
6.94) and dogs without deworming history (OR 1.90) showed a higher likelihood
of being copro-positive.
A statistically significant association (P < 0.05) was observed between
copro-prevalence and the variables investigated except for breed, anthelmintic
history and sex of the dogs.
All variables found significant (P < 0.05) were
included in the final binary logistic regression analysis; however, sex, breed
and deworming history were excluded from the model at subsequent steps (P >
0.05). The following variables or factors were significantly associated with
copro-prevalence of E. granulosus in the understudied dog population:
Age, stray dog status, feeding habit (raw meat), BCS 1–3, and previous
intestinal disease status (Table 4).
Owned/domesticated dogs’
results
The highest
prevalence was found in dogs > 3 years of age (9.52%; OR 3.55). Female dogs
(6.45%; OR 1.11), dogs with no anthelmintic treatment history (12.00%; OR
6.84), those in BCS 1–3 (11.11%; OR 6.22) and previous lower intestinal
condition (11.40%; OR 4.15) were mostly positive. The sex of dogs was the only
variable that was found to be statistically insignificant (P > 0.05) while the others were associated significantly (P < 0.05) with prevalence (Table 5).
Dogs kept as pets showed higher prevalence (7.38%; OR
1.55) than the working/shepherd dogs (4.76%) but this difference was
statistically insignificant (P > 0.05).
Further, the prevalence in dogs fed with raw meat was higher (11.85%) than
those fed with non-meat items and was statistically significant (P < 0.05). About breed
susceptibility, Grey Hound was the most copro-positivity breed (15.62%) but
association of prevalence and breed difference was statistically
non-significant (P > 0.05).
Stray/feral dogs’ results
Prevalence
was higher in young dogs with ≤ 3 years (15.56%; OR 9.07). Female dogs
(11.76%; OR 1.29), those in BCS 1–3 (23.08%; OR 8.58), dogs with previous
intestinal disease condition (18.18%; OR 7.09). Sex was the only variable that
was found to be associated with prevalence but was non-significantly (P > 0.05) (Table 6).
Table
3: Risk factors and univariable analysis for the copro-prevalence of Echinococcus granulosus antigen in owned and
stray/feral dogs
|
Variables |
Category |
Positive/
Tested |
Prevalence
(95% CI) |
OR
(95% CI) |
Chi-square |
P-value |
|
Age |
Up
to 3 |
19/274 |
6.93
(4.48-10.57) |
1.06
(0.42-2.79) |
27.43 |
0.037* |
|
More
than 3 |
6/94 |
6.38
(2.96-13.23) |
- |
|||
|
Sex |
Female |
15/172 |
8.72
(5.36-13.89) |
1.71
(0.75-3.90) |
21.77 |
0.334 |
|
Male |
10/196 |
5.10
(2.79-9.13) |
- |
|||
|
Anthelmintic
medication |
No |
16/178 |
8.98
(5.61-14.1) |
1.90
(0.82-4.39) |
14.66 |
0.360 |
|
Yes |
9/190 |
4.73
(2.51-8.76) |
- |
|||
|
Companionship |
Stray/feral |
7/72 |
9.72
(4.79-18.73) |
1.60
(0.65-3.95) |
23.65 |
0.029* |
|
Pet/domesticated |
18/296 |
6.08
(3.88-9.41) |
- |
|||
|
Raw
meat |
Yes |
14/169 |
8.28
(5.00-13.42) |
2.63
(0.85-8.15) |
26.95 |
0.018* |
|
No |
4/127 |
3.14
(1.23-7.82) |
- |
|||
|
BCS |
1-3 |
19/175 |
10.86
(7.06-16.34) |
5.75
(0.77-43.21) |
7.75 |
0.0208* |
|
4-6 |
5/140 |
3.57
(1.53-8.09) |
3.04
(1.11-8.32) |
|||
|
7-9 |
1/53 |
1.89
(0.33-9.95) |
- |
|||
|
Apparent
intestinal status |
Diseased |
19/186 |
10.22
(6.64-15.41) |
3.06
(1.20-7.83) |
5.95 |
0.0147* |
|
Healthy |
6/180 |
3.33
(1.53-7.08) |
- |
|||
|
Breed |
Grey
Hound |
5/32 |
15.62
(6.87-31.76) |
6.94
(0.39-123.52) |
8.14 |
0.7740 |
|
Bulldog |
4/40 |
10
(3.96-23.05) |
1.56
(0.39-6.19) |
|||
|
Stray |
7/72 |
9.72
(4.79-18.73) |
1.61
(0.48-5.38) |
|||
|
Alsatian |
1/12 |
8.33
(1.49-35.38) |
1.88
(0.21-16.41) |
|||
|
Bull
Terrier |
2/25 |
8
(2.22-24.97) |
1.95
(0.36-10.60) |
|||
|
German
Shepherd |
3/53 |
5.66
(1.94-15.37) |
2.76
(0.63-12.14) |
|||
|
Labrador |
2/40 |
5
(1.38-16.50) |
3.13
(0.58-16.82) |
|||
|
Owned
ND |
2/50 |
4
(1.1-13.46) |
3.91
(0.73-20.97) |
|||
|
Siberian
Husky |
0/3 |
0
(0-56.15) |
- |
|||
|
Doberman |
0/5 |
0
(0-43.45) |
- |
|||
|
Cocker
Spaniel |
0/6 |
0
(0-39.03) |
- |
|||
|
Rottweiler |
0/10 |
0
(0-27.75) |
- |
|||
|
Shih
Tzu |
0/20 |
0
(0-16.11) |
- |
*statistically
significant (P < 0.05); CI
confidence interval; OR odds ratio
Table 4: Final binary logistic regression analyses for the
prediction of Echinococcus granulosus in dogs from three
districts (Lahore, Islamabad and Faisalabad) of Punjab Province, Pakistan
|
Variable |
Comparison |
P-value |
|
Age
≤ 3 years (n = 274) |
>
3 years (n = 94) |
0.038* |
|
Feral
dog (n = 72) |
Companion
dog (n = 296) |
0.022* |
|
Raw
meat feeding (n = 169) |
Other
feed stuff (n = 127) |
0.042* |
|
BCS
1-3 (n = 175) |
BCS
4-9 (n = 193) |
0.031* |
|
Previous
intestinal disease (n = 186) |
No
previous intestinal disease (n = 180) |
0.029* |
*statistically significant (P < 0.05)
Discussion
Dogs have proven to be the most successful among other
canids’ species because of their domestication and proximity to man as
companion animals (Knobel et al. 2008; Paul et al. 2010). On the
contrary, their close association with humans and behaviors remain a leading
risk to public health. Several parasites are harbored by dogs, thus posing a
potential risk of disease transmission to humans and livestock (Moro and Abah
2018). In Pakistan, information on echinococcosis in dogs is scarce. However, a
few studies conducted in limited geographical areas on hydatidosis have
confirmed the presence of CE in ruminants (Mirani et al. 2002; Iqbal et
al. 2012).
Copro-ELISA is a widely used technique for field surveys
and field diagnosis of CE in dogs and has been applied effectively in previous
studies (El-Shazly et al. 2007; Acosta-Jamett et al. 2010;
Carmena and Cardona 2014). The main advantage of copro-ELISA over antibody
detection in serum is its correlation with current infection (Adediran et al.
2014).
To the best of our knowledge, there is no report on
canine echinococcosis in Pakistan, although some studies are available on
hydatidosis in livestock. In this study, the overall prevalence was found to be
6.79% which is quite high considering the zoonotic potential of Echinococcus. Meanwhile, the overall
prevalence observed in this study is comparable to other studies conducted in
different geographical regions of the world. For instance, Prathiush et al. (2008) found an overall
Echinococcus copro-prevalence of
4.35% in dogs from India. Svobodová and
Lenska (2002) also reported an 8.1% copro-prevalence of Echinococcus in dogs in the Czech Republic while another study in
Argentina demonstrated 7.3% prevalence (Cavagión et al. 2005). In
contrast, higher prevalence has been reported in Uruguay 22.7% (Craig et al.
1995), Libya 21.6% (Buishi et al. 2005), and Peru where copro-prevalence
ranged between 46 and 82% (Moro et al. 1999; Lopera et al. 2003;
Moro et al. 2005). Additionally, prevalence of E. granulosus infection up to
35.3% has been reported in dogs in Sidi Kacem Province of Morocco (Dakkak et
al. 2017). In some cases, the prevalence differs between local areas within
a region or country but the values are often non-significant. For example, the
report from different Libyan districts; Alkhums, Tripoli and Azahwia (38.7, 17.5 and 38.7%, respectively) (Buishi et
al. 2005). This observation is in agreement with our findings which showed
a prevalence of 9.80, 7.97 and 5.02% in Lahore, Islamabad and, Faisalabad
districts, respectively with no significant differences (P > 0.05).
Table
5: Risk factors and univariable analysis for the copro-prevalence of Echinococcus granulosus antigen in owned dogs
|
Variables |
Category |
Positive/
Tested |
Prevalence
(95% CI) |
OR
(95% CI) |
Chi-square |
P-value |
|
Age |
More
than 3 |
14/147 |
9.52
(5.76-15.35) |
3.55
(1.15-10.99) |
5.37 |
0.0205* |
|
Up
to 3 |
4/149 |
2.68
(1.05-6.69) |
- |
|||
|
Sex |
Male |
8/124 |
6.45
(3.3-12.21) |
1.11
(0.43-2.88) |
0.05 |
0.8313 |
|
Female |
10/172 |
5.81
(3.19-10.37) |
- |
|||
|
Anthelmintic
medication |
No |
15/125 |
12
(7.41-18.86) |
6.84
(1.95-24.04) |
11.60 |
0.0007* |
|
Yes |
3/171 |
1.75
(0.6-5.02) |
- |
|||
|
Purpose |
Pet |
11/149 |
7.38
(4.17-12.73) |
1.55
(0.59-4.10) |
0.79 |
0.3747 |
|
Working |
7/147 |
4.76
(2.32-9.5) |
- |
|||
|
Raw
meat |
Yes |
16/135 |
11.85
(7.43-18.38) |
9.54
(2.17-42.04) |
12.73 |
0.0004* |
|
No |
2/161 |
1.24
(0.34-4.41) |
- |
|||
|
BCS |
1-3 |
15/135 |
11.11
(6.85-17.52) |
6.22
(1.40-27.61) |
9.68 |
0.0079* |
|
4-6 |
1/49 |
2.04
(0.36-10.69) |
5.44
(0.71-41.49) |
|||
|
7-9 |
2/112 |
1.79
(0.49-6.28) |
- |
|||
|
Apparent
intestinal status |
Disease |
13/114 |
11.40
(6.78-18.53) |
4.15
(1.45-11.91) |
8.00 |
0.0047* |
|
Sick |
5/182 |
2.75
(1.18-6.27) |
- |
|||
|
Breed |
Grey
Hound |
5/32 |
15.62
(6.87-31.76) |
6.94
(0.39-123.52) |
7.96 |
0.7168 |
|
Bulldog |
4/40 |
10
(3.96-23.05) |
1.56
(0.39-6.19) |
|||
|
Alsatian |
1/12 |
8.33
(1.49-35.38) |
1.88
(0.21-16.41) |
|||
|
Bull
Terrier |
2/25 |
8
(2.22-24.97) |
1.95
(0.36-10.60) |
|||
|
German
Shepherd |
3/53 |
5.66
(1.94-15.37) |
2.76
(0.63-12.14) |
|||
|
Labrador |
2/40 |
5
(1.38-16.50) |
3.13
(0.58-16.82) |
|||
|
Owned
ND |
2/50 |
4
(1.1-13.46) |
3.91
(0.73-20.97) |
|||
|
Siberian
Husky |
0/3 |
0
(0-56.15) |
- |
|||
|
Doberman |
0/5 |
0
(0-43.45) |
- |
|||
|
Cocker
Spaniel |
0/6 |
0
(0-39.03) |
- |
|||
|
Rottweiler |
0/10 |
0
(0-27.75) |
- |
|||
|
Shih
Tzu |
0/20 |
0
(0-16.11) |
- |
*statistically
significant (P < 0.05); CI
confidence interval; OR odds ratio
Table
6: Risk factors and univariable analysis for the copro-prevalence of Echinococcus granulosus antigen in stray/feral
dogs
|
Variables |
Category |
Positive/
Tested |
Prevalence
(95% CI) |
OR
(95% CI) |
Chi-square |
P-value |
|
Age |
Up
to 3 |
7/45 |
15.56
(7.75-28.79) |
9.07
(0.52-156.90) |
3.99 |
0.0458* |
|
More
than 3 |
0/27 |
0
(0-12.46) |
- |
|||
|
Sex |
Female |
2/17 |
11.76
(3.29-34.33) |
1.29
(0.24-7.02) |
0.09 |
0.7694 |
|
Male |
5/55 |
9.09
(3.95-19.58) |
- |
|||
|
BCS |
1-3 |
6/26 |
23.08
(11.04-42.05) |
8.58
(0.49-149.84) |
6.66 |
0.0357* |
|
4-6 |
1/29 |
3.45
(0.61-17.18) |
6.69
(0.78- 57.22) |
|||
|
7-9 |
0/17 |
0
(0-18.43) |
- |
|||
|
Apparent
intestinal status |
Diseased |
6/33 |
18.18
(8.61-34.39) |
7.09
(0.83-60.26) |
4.06 |
0.0439* |
|
Healthy |
1/39 |
2.56
(0.450-13.17) |
- |
*statistically
significant (P < 0.05); CI
confidence interval; OR odds ratio
In this study, a statistically significant negative
correlation (P < 0.05) was observed
between copro-positivity and age which is in disparity with the results of
Adediran et al. (2014). Dogs up to 3 years in age were found to be more
likely to be copro-positive than older dogs. This is in agreement with reports
of high worm burden in young dogs compared to adults due to the development of
acquired immunity over time (Lahmar et al. 2007). Moreover, age-related
variations in dog behavior and management also advocate for differences in
prevalence between young and adult dogs (Torgerson et al. 2003). Also,
immunocompromised status increases susceptibility to infection and the captive
dogs from rural areas fall under this category as they lack proper nutrition
and medical attention.
Higher prevalence in female than in male dogs was
observed in the current study and is in line with the findings of Adediran et al. (2014) but contrast
the report of Budke (2004). However further analysis showed that there was no
association (P > 0.05) between sex
and prevalence of canine echinococcosis which has also been demonstrated in
previous studies (Siavashi and Motamedi 2006; Öge
et al. 2017).
In the current study, we investigated dog breeds as a
potential risk factor for Echinococcus
infection and samples collected from 13 different breeds demonstrated the
highest prevalence in Grey Hound (15.62%) breed and lowest in client-owned
non-descript breeds (4.00%). However, the difference in prevalence was
statistically non-significant (P <
0.05). To best of our knowledge, this result presents variation in prevalence
according to dog breeds for the first time and as risk factor for canine
echinococcosis. We also found that previous de-worming status is not the
significant predictor (P > 0.05)
of copro-positivity which is in contrast to the findings of Acosta-Jamett et
al. (2014) who found significantly higher (P < 0.05) copro-prevalence in dogs which were not dewormed
previously. The results of this study showed that prevalence in stray dogs was
higher and statistically different (P <
0.05) when compared to restrained/companion dogs which is expected as
free-roaming dogs are apparently more exposed due to easy access to hydatid
offal (Buishi et al. 2005).
Conclusion
The results of this study demonstrate that
echinococcosis is prevalent among dogs hosted in different prefectures of
Pakistan and suggest that more epidemiological and molecular studies focusing
on intermediate hosts including humans are warranted to further ascertain the
risk posed by canine population in order to design effective control
strategies.
Acknowledgments
This study was part of a PhD research supported by
Lanzhou Veterinary Research Institute, Lanzhou, People’s Republic of China. We would like to thank the National Key Research and Development Program of China
(2017YFD0501301), National Key
Basic Research Program (973 Program) of China (2015CB150300) and the Central Public-interest
Scientific Institution Basal Research Fund (1610312017001; 1610312016012) for their
funding support. We are also thankful to the Veterinary Assistants at the
Department of Clinical Medicine and Surgery, University of Agriculture,
Faisalabad for their assistance during sample collection.
Author Contributions
Conceptualization, Mughees Aizaz Alvi, Muhammad Saqib,
Li Li, Wan-Zhong Jia; methodology, Mughees Aizaz Alvi, Muhammad Saqib, Hong-Bin
Yan, Warda Qamar; formal analysis, Mughees Aizaz Alvi, Muhammad Haleem Tayyab,
Muhammad Masood Tahir; investigation, Mughees Aizaz Alvi, Warda Qamar, Waqas
Altaf, Muhammad Usman, Ali Hassan, Muhammad Rashid Khalid Bajwa; resources,
Wan-Zhong Jia; data curation, Mughees Aizaz Alvi, John Asekhaen Ohiolei;
writing—original draft preparation, Mughees Aizaz Alvi; writing—review and
editing, John Asekhaen Ohiolei, Hong-Bin Yan, Wan-Zhong Jia; project
administration, Bao-Quan Fu, Wan-Zhong Jia ; funding acquisition, Wan-Zhong Jia.
Conflict of Interest
The authors
declare that there is no conflict of interest regarding the publication of this
article
Data Availability Declaration
All the data
pertaining to this work is mentioned in the manuscript
Conformation to Ethical Guidelines for Research on
Animals
Not
applicable
References
Acosta-Jamett G, T Weitzel, B Boufana,
C Adones, A Bahamonde, K Abarca, PS Craig, I Reiter-Owona (2014). Prevalence
and risk factors for echinococcal infection in a rural area of Northern Chile:
A household-based cross-sectional study. PLoS
Negl Trop Dis 8; Article e3090
Acosta-Jamett G, S Cleaveland, M
Barend, AA Cunningham, H Bradshaw, PS Craig (2010). Echinococcus granulosus
infection in domestic dogs in urban and rural areas of the Coquimbo region,
north-central Chile. Vet Parasitol 169:117‒122
Adediran OA, TU Kolapo, EC Uwalaka
(2014). Echinococcus granulosus prevalence in dogs in
Southwest Nigeria. J Parasitol Res 2014:1-6
Anonymous (1996). How to determine a
cat’s or dog’s age [online. Available from: http://www.ruralareavet.org/PDF/Physical_Exam-How_to_Determine_Age.pdf
Baldwin K, J Bartges, T Buffington, LM
Freeman, M Grabow, J Legred, D Ostwald (2010). AAHA nutritional assesment
guidelines for dogs and cats. J Amer Anim
Hosp Assoc 46:285‒296
Benito A, D Carmena (2005).
Double-antibody sandwich ELISA using biotinylated antibodies for the detection
of Echinococcus granulosus coproantigens in dogs. Acta Trop 95:9‒15
Budke CM (2004). Echinococcosis on the
Tibetan Plateau. Ph.D. Dissertation. University
of Basel, Switzerland
Buishi I, E Njoroge, O Bouamra, PS Craig
(2005). Canine echinococcosis in northwest Libya: assessment of coproantigen
ELISA, and a survey of infection with analysis of risk-factors. Vet Parasitol
130:223‒232
Carmena D, GA Cardona (2014). Echinococcosis in wild carnivorous species:
Epidemiology, genotypic diversity, and implications for veterinary public
health. Vet Parasitol
202:69‒94
Cavagión L, A Perez, G Santillan, F Zanini, O Jensen, L Saldía, M Diaz,
Guatavo Cantoni, E Herrero, MT Costa, M Volpe, D Araya, NA Rubianes, C Aguado,
G Meglia, E Guarnera, E Larrieu (2005). Diagnosis of cystic echinococcosis on
sheep farms in the south of Argentina: areas with a control program. Vet Parasitol
128:73‒81
Craig P, R Gasser, L Parada, P Cabrera, S Parietti, C Borgues, A Acuttist,
J Agulla, K Snowden, E Paolillo (1995). Diagnosis of canine echinococcosis:
comparison of coproantigen and serum antibody tests with arecoline purgation in
Uruguay. Vet Parasitol 56:293‒301
Dakkak A, I El-Berbri, A Petavy, F
Boué, M Bouslikhane, OF Fihri, S Welburn, MJ Ducrotoy (2017). Echinococcus granulosus infection in dogs in Sidi Kacem Province (north-West
Morocco). Acta Trop 165:26‒32
El-Shazly AS, S Awad, I Nagaty, T Morsy
(2007). Echinococcosis in dogs in urban and rural areas in Dakahlia
Governorate, Egypt. J Egypt Soc Parasitol 37:483‒492
Ghabdian S, H Borji, A Naghibi (2017).
Molecular identification of Echinococcus
granulosus strain in stray dogs from
Northeastern Iran. Vet Parasitol Reg Stud Rep 9:6‒8
Hidalgo A, A Melo, F Romero, J
Villanueva, C Carrasco, P Jara, J Venegas, FF Salamanca (2019). A PCR-RFLP
assay for discrimination of Echinococcus
granulosus sensu stricto and Taenia spp in dogs stool. Exp Parasitol
200:42‒47
Ingole R, H Khakse, M Jadhao, SR Ingole
(2018). Prevalence of Echinococcus
infection in dogs in Akola district of Maharashtra (India) by Copro-PCR. Vet Parasitol
Reg Stud Rep 13:60‒63
Iqbal HJ, A Maqbool, M Lateef, M Khan,
M Riaz, A Mahmood, FA Atif, Z Ali, MS Ahmad (2012). Studies on hydatidosis in
sheep and goats at Lahore, Pakistan. J
Anim Plant Sci 22:894‒897
Knobel
DL, MK Laurenson, RR Kazwala, LA Boden, S Cleaveland (2008). A cross-sectional
study of factors associated with dog ownership in Tanzania. BMC Vet Res 4; Article 5
Lahmar
S, B Boufana, H Bradshaw, P Craig (2007). Screening for Echinococcus granulosus
in dogs: Comparison between arecoline purgation, coproELISA and coproPCR with
necropsy in pre-patent infections. Vet
Parasitol 144:287‒292
Liu CN, ZZ Lou, L Li, HB Yan, D Blair,
MT Lei, JZ Cai, YL Fan, JQ Li, BB Fu, YR Yang, DP McManus, WZ Jia (2015).
Discrimination between E. granulosus sensu stricto, E. multilocularis and E. shiquicus using a
multiplex PCR assay. PLoS Negl Trop Dis
9; Article e0004084
Lopera L, PL Moro, A Chavez, G Montes,
A Gonzales, RH Gilman (2003). Field evaluation of a coproantigen enzyme-linked
immunosorbent assay for diagnosis of canine echinococcosis in a rural Andean
village in Peru. Vet Parasitol 117:37‒42
Mirani A, S Buoghio, N Akhter (2002).
Age and size-wise distribution of echinococcosis in buffaloes slaughtered at
the Larkana Abattoir. Pak J Appl
Sci 2:837‒838
Moro KK, AE Abah (2018). Epizootiology
of zoonotic parasites of dogs in Abua Area of Rivers State, Nigeria. Vet Anim Sci 7; Article 100045
Moro PL, L Lopera, N Bonifacio, A
Gonzales, RH Gilman, MH Moro (2005). Risk factors for canine echinococcosis in
an endemic area of Peru. Vet Parasitol 130:99‒104
Moro PL, N Bonifacio, RH Gilman, L
Lopera, B Silva, R Takumoto, M Verastegui, L Cabrera (1999). Field diagnosis of
Echinococcus granulosus infection among intermediate and definitive hosts in an
endemic focus of human cystic echinococcosis. Trans Roy Soc Trop Med Hyg 93:611‒615
Mulinge E, J Magambo, D Odongo, S
Njenga, E Zeyhle, C Mbae, D Kagendo, F Addy, D Ebi, M Wassermann, P Kern, T
Romig (2018). Molecular characterization of Echinococcus
species in dogs from four regions of Kenya. Vet
Parasitol 255:49‒57
Newcombe RG (1998). Two‐sided
confidence intervals for the single proportion: comparison of seven methods. Stat Med
17:857‒872
Öge H, S Öge, B Gönenç, O
Sarımehmetoğlu, G Özbakış (2017). Coprodiagnosis of Echinococcus granulosus infection in dogs from Ankara, Turkey. Vet Parasitol
242:44‒46
Pakistan Meteorological Department
[online]. [cited 2019 Oct 30].
Available from: http://www.pmd.gov.pk/Observatories/index.html
Paul M, L King, EP Carlin (2010).
Zoonoses of people and their pets: a US perspective on significant
pet-associated parasitic diseases. Trends
Parasitol 26:153‒154
Prathiush PR, ED Placid, KJG Ananda
(2008). Diagnosis of Echinococcus granulosus infection in dogs by a
coproantigen sandwich ELISA. Vet Arhiv 78:297‒305
Rashid M, MI Rashid, H Akbar, L Ahmad,
MA Hassan, K Ashraf, K Saeed, M Gharbi (2018). A systematic review on modelling
approaches for economic losses studies caused by parasites and their associated
diseases in cattle. Parasitology
146:129‒141
Rossi A, JM Marqués, CM Gavidia, AE
Gonzalez, C Carmona, HH García, JA Chabalgoity (2012). Echinococcus granulosus:
different cytokine profiles are induced by single versus multiple experimental
infections in dogs. Exp Parasitol
130:110‒115
Siavashi M, G Motamedi (2006). Evaluation of a coproantigen enzyme-linked
immunosorbent assay for the diagnosis of canine echinococcosis in Iran. Helminthologia 43:17‒19
Svobodová V, B Lenska (2002).
Echinococcosis in dogs in the Czech Republic. Acta Vet Brno 71:347‒350
Thapa NK, MT Armua-Fernandez, D
Kinzang, RB Gurung, P Wangdi, D Deplazes (2017). Detection of Echinococcus granulosus and Echinococcus
ortleppi in Bhutan. Parasitol Intl 66:139‒141
Torgerson PR, BS Shaikenov, AT
Rysmukhambetova, AE Ussenbayev, AM Abdybekova, KK Burtisurnov (2003). Modelling
the transmission dynamics of Echinococcus
granulosus in dogs in rural Kazakhstan.
Parasitology 126:417‒424
Wang L, Q Wang, H Cai, H Wang, Y Huang, Y Feng, X Bai, M
Qin, S Manguin, L Gavotte, W Wu, R Frutos (2021). Evaluation of fecal
immunoassays for canine Echinococcus infection
in China. PLoS Negl Trop Dis 15;
Article e0008690
WHO - World Health Organization (2015).
Available at: https://www.who.int/echinococcosis/epidemiology/en/ (Accessed [October
30, 2019]
WHO/OIE (World
Health Organization/World Organization for Animal Health) (2001).
Echinococcosis in animals: clinical aspects, diagnosis and treatment. WHO/OIE
Manual on Echinococcosis in Humans and Animals: A Public Health Problem of
Global Concern. Chapter 3. , WHO/OIE, Paris,
France
Zhang Y, JM Bart, P Giraudoux, P Craig,
D Vuitton, H Wen (2006). Morphological and molecular characteristics of Echinococcus multilocularis and Echinococcus
granulosus mixed infection in a dog
from Xinjiang, China. Vet Parasitol 139:244‒248