The Influence of Giardia duodenalis on the Occurrence of Clinical Signs in Dogs

Giardia duodenalis infections are common in dogs and are mainly caused by assemblages C and D. The aim of this study was to investigate the correlation between the presence of Giardia duodenalis and different Giardia assemblages detected in symptomatic and asymptomatic dogs and the occurrence of certain clinical signs. All the dogs included (n = 82) were clinically examined, and fecal samples were examined for other parasites and Clostridium spp. Also, G. duodenalis assemblages were detected and the occurrence of certain clinical signs was assessed. A total of 42/82 (51.2%) dogs were symptomatic and had one or more gastrointestinal signs, and 40/82 (48.8%) dogs were asymptomatic. G. duodenalis was found in 25/82 (30.5%) dogs: assemblage C in 10/25 (40%) and assemblage D in 15/25 (60%). Only Cryptosporidium spp. showed a higher coinfection rate with G. duodenalis but that did not have an influence on clinical sign appearance. There was no correlation between the presence of different assemblages of G. duodenalis and the sex of the host or the duration and appearance of certain clinical signs, except the presence of mucus in feces, which was more frequent in dogs invaded with G. duodenalis assemblage C. Further research of other assemblages is needed.

Coagulation Abnormalities in Dogs with Parvoviral Enteritis

Hemostatic alterations have been documented in dogs with canine parvoviral enteritis. This study's aims were to measure the standard coagulation parameters, and to assess the relationship between them and the clinical variables in dogs with canine parvoviral enteritis. Nine client-owned dogs with a canine parvoviral infection were included in a prospective, observational clinical study. Clinical score and coagulation status were assessed at admission. All nine dogs showed alterations of three or more standard coagulation variables. A correlation analysis evidenced a significantly high positive correlation between the activated partial thromboplastin time and clinical score. The present study concurs that dogs with canine parvoviral enteritis have coagulation disorders that are detectable by measuring the standard coagulation parameters.

Prevalence, Risk Factors and Genotypes of Giardia duodenalis in Sheltered Dogs in Tuscany (Central Italy)

In sheltered dogs, the prevalence of Giardia duodenalis is frequently high and may include potential zoonotic genotypes. The prevalence, genotypes and potential risk factors of G. duodenalis were assessed in 168 dogs from four kennels (Pistoia, Prato, Florence, Valdarno) in Tuscany, central Italy and compared with data from previous Italian studies. The prevalence of other intestinal parasites was also investigated. Individual dog faecal samples collected from each kennel were examined by parasitological techniques and a rapid immunoassay for the detection of G. duodenalis and Cryptosporidium faecal antigens. On Giardia-positive samples, molecular analysis was performed for genotype identification. Overall, 69 dogs scored positive for G. duodenalis (41%), but significant differences (p ≤ 0.05) were found among the four kennels and sampling seasons. The potentially zoonotic assemblages A and B and the canine-specific assemblage C (Pistoia: A-AII, B, C; Prato: A-AII, B; Florence: A-AII; Valdarno: A and C) were identified. Toxocara canis (8.9%), Trichuris vulpis (3.6%), hookworms (1.19%) and Cryptosporidium sp. (0.6%) were also identified. The high prevalence of G. duodenalis and the identification of potentially zoonotic genotypes in all examined kennels underline the need to improve routine parasite monitoring and control measures and to provide insights into the zoonotic potential of G. duodenalis.

Environmental Contamination by Dog Feces in Touristic Areas of Italy: Parasitological Aspects and Zoonotic Hazards

Public spaces are common sites of fecal contamination which is concerning considering the prevalence rates of gastrointestinal pathogens carried by pets. Multiple pet-bound parasite species capable of infecting humans have previously been reported in fecal samples collected from urban areas around the globe, including Italy. In addition, the presence of gastrointestinal parasites has recently been shown in pets from the island of Sardinia, a well-known touristic destination. For these reasons, this study aims to evaluate the level of fecal contamination of two of the most important cities on Sardinia. Furthermore, the presence of endoparasites in fecal samples collected was also investigated to assess the parasitological risks associated with such contamination. A grid approach using a geographical information system was applied, followed by transect counting and sampling. A total of 956 and 220 dog feces with an average feces count of 4.7 and 2.6 per 100 linear meters were found for Sassari and Alghero, respectively. In Sassari 15.6% (52/333) and in Alghero 6.8% (6/88) of the samples tested positive for parasitic elements. Hookworms, Strongyloides stercoralis, Toxocara sp., and Trichuris vulpis were among the parasites most identified. This study showed significant urban contamination of both Sassari and Alghero with dog feces and the parasites within them, including potentially zoonotic species. The general public as well as tourists visiting the island should be aware of the risks associated with this and appropriate measures taken.

Giardia duodenalis infection in dogs from the metropolitan area of Lisbon, Portugal: prevalence, genotyping and associated risk factors

Abstract

Giardia duodenalis is a cosmopolitan enteric protozoan that affects a wide range of vertebrates, including humans and dogs. Genetic characterisation reveals eight different assemblages, with A and B having been found mainly in humans and several other animals, and thus considered potentially zoonotic, while C and D are adapted to infect dogs. This study aimed to determine the prevalence of G. duodenalis, their distribution into assemblages, and risk factors associated with their infection of dogs from the metropolitan area of Lisbon. Giardia duodenalis cysts were microscopically identified in 33.8% (27/80) of the faecal samples analysed. Multivariate logistic regression analysis revealed that dogs under 6 months of age and from both breeders and shelters, had a significantly higher risk of being infected with G. duodenalis. Based on phylogenetic analysis of the partial coding sequences for β-giardin, glutamate dehydrogenase, and triosephosphate isomerase, the parasites found in three dog isolates were typed as G. duodenalis assemblage C, 11 were typed as D, and four were typed as C or D, depending on the targeted genes. The risk to public health seems to be reduced, as no genotypes with zoonotic potential have been detected. Nevertheless, better health management towards a minimisation of the environmental faecal pollution, as well as an increase in the awareness of health professionals, dog owners, dog breeders and caregivers regarding the risks posed by this protozoan to the health of animals and humans, are recommended.

Graphic abstract

Giardia duodenalis infection in dogs affected by primary chronic enteropathy

Background:

Canine primary chronic enteropathy (CE) includes a heterogeneous group of diseases characterized by chronic gastrointestinal signs.

Aim:

This study evaluated the occurrence of Giardia duodenalis infection in primary CE-affected dogs.

Methods:

Forty-seven CE-affected dogs of different age and sex were enrolled in the study. For each dog, frequency of defecation, fecal consistency, and eventual fecal abnormalities were evaluated. A clinical scoring index of CE severity (clinical chronic enteropathy activity index) was also assessed, and the type of enteropathy was retrospectively classified. For parasitological analysis, fresh fecal samples collected from each dog were examined by fresh and Lugol stained smears, flotation test, and a rapid immunoassay. Giardia duodenalis genotypes were identified by molecular analysis. Differences of clinical parameters between G. duodenalis positive and G. duodenalis negative dogs were statistically evaluated.

Results:

Among the CE canine patients, 16 out of 47 (34%) dogs were found positive for G. duodenalis and assemblages C and D were identified. No statistical differences emerged according to the types of CE between G. duodenalis-positive and G. duodenalis-negative dog groups. The clinical index of CE severity was indicative of significant less severe clinical forms in G. duodenalis-positive dogs (p = 0.037).

Conclusion:

Results here obtained shows how G. duodenalis may be present in primary CE-affected dogs and further investigations are needed to clarify the real significance of mild clinical presentation in G. duodenalis-positive dogs affected by CE.

Intestinal parasite infections in dogs affected by multicentric lymphoma and undergoing chemotherapy

Prevalence and species composition of intestinal parasites were evaluated in dogs affected by high-grade multicentric lymphoma and undergoing chemotherapy and in control healthy dogs. Obtained data were statistically analyzed. The overall prevalence of intestinal parasite infections was 33.3%. In lymphoma dogs, the prevalence of protozoa infections (46.7%) was significantly higher (p < 0.05) than that of helminth infections (6.7%) and Giardia duodenalis, Cryptosporidium spp., Neospora caninum, Cystoisospora ohioensis-complex, Entamoeba sp. and Spirocerca lupi were identified. In the control group, only 3/15 dogs (20%) were found positive and no statistically significant differences emerged regarding helminth (hookworms and Toxocara canis) and protozoa (G. duodenalis) infections. Results from this study may suggest a potential higher prevalence of opportunistic intestinal protozoa, including some potentially zoonotic species, in dogs affected by high-grade multicentric lymphoma, emphasizing the need to monitor lymphoma-affected dogs for these protozoa, especially those undergoing chemotherapy.

Occurrence and molecular epidemiology of Giardia duodenalis infection in dog populations in eastern Spain

Background

Giardia duodenalis is one of the most common enteric parasites in domestic animals including dogs. Young animals are more prone to the infection, with clinical manifestations ranging from asymptomatic to acute or chronic diarrhoea. Dogs are primarily infected by canine-specific (C-D) assemblages of G. duodenalis. However, zoonotic assemblages A and B have been increasingly documented in canine isolates, raising the question of whether and to which extent dogs can act as natural reservoirs of human giardiosis.

Methods

In this cross-sectional epidemiological survey we assessed the molecular diversity of G. duodenalis in dogs in the province of Castellón, Eastern Spain. A total of 348 individual faecal samples from sheltered (n = 218), breeding (n = 24), hunting (n = 68), shepherd (n = 24), and pet (n = 14) dogs were collected between 2014 and 2016. Detection of G. duodenalis cysts in faecal material was carried out by direct fluorescence microscopy as a screening test, whereas a qPCR targeting the small subunit ribosomal RNA gene of the parasite was subsequently used as a confirmatory method.

Results

Giardia duodenalis was detected in 36.5% (95% CI: 31.6–41.7%) of dogs. No significant differences in prevalence rates could be demonstrated among dogs according to their sex and geographical origin, but breeding (45.8%; 95% CI: 27.9–64.9%) and sheltered (40.4%; 95% CI: 34.1–47.0%) dogs harboured significantly higher proportions of G. duodenalis. Multi-locus sequence-based genotyping of the glutamate dehydrogenase and β-giardin genes of G. duodenalis allowed the characterization of 35 canine isolates that were unambiguously assigned to assemblages A (14.3%), B (22.9%), C (5.7%), and D (37.1%). A number of inter-assemblage mixed infections including A + B (11.4%), A + D (2.9%), and A + B + D (5.7%) were also identified.

Conclusions

Data presented here are strongly indicative of high infection pressures in kennelled animals. Zoonotic sub-assemblages AII, BIII, and BIV were responsible for a considerable proportion of the G. duodenalis infections detected, but very few of the genotypes identified have been previously documented in Spanish human populations. Although possible, zoonotic transmission between dogs and humans seems an infrequent event in this Spanish region.

Electronic supplementary material

The online version of this article (10.1186/s12917-018-1353-z) contains supplementary material, which is available to authorized users.

Prevalence, genotyping and risk factors of Giardia duodenalis from dogs in Vietnam

This study was carried out to determine the prevalence, genotypes/assemblages and possible risk factors associated with Giardia duodenalis infection in dogs in central Vietnam. A total of 209 dog fecal samples, randomly collected from private owned dogs (n=105) and dogs from stores (n=104), were examined for Giardia cysts by microscopy. Positive samples were genotyped by PCR-sequence analysis of β-giardin and triosephosphate isomerase genes markers. Risk factors were studied using a structured questionnaire and collected data were analyzed by univariate and multivariate logistic regression analyses. Results indicated that the overall infection rate was 8.6% (18/209) with the detected parasites were belonging to the non-zoonotic assemblages C and D. Age, gender and origin of animals were the main risk factors associated with G. duodenalis infection in dogs under study. Occurrence of infection was more likely in young animals compared to old ones and in females compared to males. Dogs originated from stores were more prone to Giardia infection compared to private owned counterparts.

Endoparasites detected in faecal samples from dogs and cats referred for routine clinical visit in Sardinia, Italy

This study aimed to update data on the prevalence of intestinal and lung parasitic infections in owned dogs and cats in Sardinia, Italy. Examinations on faecal samples from 619 dogs and 343 cats routinely referred to the Veterinary Teaching Hospital of the University of Sassari were performed between the years of 2011 and 2015. Individual faecal samples were analysed using the Wisconsin technique for copro-microscopic examination and the Baermann technique for the presence of lungworm larvae. Endoparasites were found in 34.9% and 43.4% of examined dogs and cats, respectively. Helminthic infections (21.2% in dogs and 32.6% in cats) occurred more frequently than protozoan infections (17.9% in dogs and 17.8% in cats). In both dogs and cats, the most common parasites were ascarids (12.1% and 15.7%), Cystoisospora spp. (10.2% and 10.8%), Giardia duodenalis (9.4% and 8.5%), and hookworms (7.9% and 5.5%). Evidence of bronchopulmonary nematode infections were found in 0.8% of examined dogs and in 15.8% of examined cats. Age was identified as a risk factor, with animals younger than 6months more frequently infected than older animals, while no significant association was observed for gender. This study demonstrated that endoparasites in owned dogs and cats of Sardinia have considerably high prevalence. Veterinary practitioners and pet owners should be more aware of these infections and should adopt more effective and standardized control practices.

Prevalence and molecular characterization of Giardia duodenalis in dogs in Aydin, Turkey

The purpose of the present study was to investigate the prevalence and molecular characterization of Giardia duodenalis among dogs in Aydin, Turkey. A total of 473 faecal samples from dogs were collected. The overall prevalence of G. duodenalis was 18.8%. Higher infection rates were observed in dogs younger than three months old, from shelters, and with diarrhoea. Faecal samples of 89 dogs, diagnosed Giardia-positive by microscopy, were found positive by nested PCR. The β-giardin nested PCR assay revealed assemblage B in all samples (100%), whereas 38 of the samples were mixed with assemblage A (42%). Sequence analysis of isolates indicated sub-genotypes A3 and B4 which have been previously detected in human isolates from Turkey. The results of the present study indicated the relatively high prevalence of giardiasis and the presence of the zoonotic sub-genotypes suggesting the important role of dogs as potential reservoirs of human infections.

The prevalence of Giardia infection in dogs and cats, a systematic review and meta-analysis of prevalence studies from stool samples

Giardia has a wide range of host species and is a common cause of diarrhoeal disease in humans and animals. Companion animals are able to transmit a range of zoonotic diseases to their owners including giardiasis, but the size of this risk is not well known. The aim of this study was to analyse giardiasis prevalence rates in dogs and cats worldwide using a systematic search approach. Meta-analysis enabled to describe associations between Giardia prevalence and various confounding factors. Pooled prevalence rates were 15.2% (95% CI 13.8-16.7%) for dogs and 12% (95% CI 9.2-15.3%) for cats. However, there was very high heterogeneity between studies. Meta-regression showed that the diagnostic method used had a major impact on reported prevalence with studies using ELISA, IFA and PCR reporting prevalence rates between 2.6 and 3.7 times greater than studies using microscopy. Conditional negative binomial regression found that symptomatic animals had higher prevalence rates ratios (PRR) than asymptomatic animals 1.61 (95% CI 1.33-1.94) in dogs and 1.94 (95% CI 1.47-2.56) in cats. Giardia was much more prevalent in young animals. For cats >6 months, PRR=0.47 (0.42-0.53) and in dogs of the same age group PRR=0.36 (0.32-0.41). Additionally, dogs kept as pets were less likely to be positive (PRR=0.56 (0.41-0.77)) but any difference in cats was not significant. Faecal excretion of Giardia is common in dogs and slightly less so in cats. However, the exact rates depend on the diagnostic method used, the age and origin of the animal. What risk such endemic colonisation poses to human health is still unclear as it will depend not only on prevalence rates but also on what assemblages are excreted and how people interact with their pets.