Prevalence of intestinal parasites in dogs from public shelters in Serbia

Comparison of different molecular protocols for the detection of Uncinaria stenocephala infection in dogs

The present study aims to assess the performance of different molecular targets using various matrices of samples for the detection of Uncinaria stenocephala (US) in hookworm infected dogs. To this end, the DNA extraction was performed on the following matrices of samples: (i) larvae of US obtained from experimentally infected dogs with US with different larvae counts per microliter (µl); (ii) pure US eggs suspension in distilled water with different egg counts per µl; (iii) spiked dog fecal samples with different US eggs per gram (EPG) of feces; (iv) feces from dogs naturally infected with hookworm eggs; (v) fecal suspension with hookworm eggs recovered from the FLOTAC apparatus. All the samples were tested with four different PCR protocols targeting specific regions for the detection of both hookworms US and AC as follows: Protocol A (ITS1, 5.8 S, ITS2) and Protocol B (18 S) for the detection of both species, Protocol C (ITS1) for the detection of AC and Protocol D (ITS1) for the detection of US. The best results were obtained with DNA extracted from US larvae matrix obtained from experimentally infected dogs, showing a detection limit of 3.5 larvae/ml for the protocols A, B and D. A moderate correlation was found between the FLOTAC technique and PCR protocols B and D with respect to fecal samples from dogs naturally infected with hookworms. Indeed, PCR protocols B (18 S) and D (ITS1) gave the best results for feces and fecal suspension from naturally infected dogs. However, all the PCR protocols used showed lower sensitivity than FLOTAC technique. Perhaps, isolating US eggs in advance could help to obtain better quality and quantity of DNA, avoiding some notable factors such as inhibitors present in faecal samples. However, a further study is needed to evaluate and standardise a protocol for the recovery of parasitic elements, that could be applied prior to DNA extraction. Therefore, this could lead to a better amplification of US eggs DNA. In conclusion, our results showed that the type of sample (sample-matrix) used for the DNA extraction samples is crucial, as this affects the diagnostic sensitivity of the technique.

Gastrointestinal Parasites in Owned Dogs in Serbia: Prevalence and Risk Factors

Dogs are the most popular pets worldwide. Close contact between dogs and people increases the risk of transmission of various zoonotic parasitic infections. Given the importance of veterinary medicine in preserving the One Health concept, the aim of this research was to identify intestinal parasites that may have zoonotic potential and to evaluate risk factors (individual and environmental). The research was conducted in Serbia in 2022 and 2023 on 382 owned dogs, using qualitative methods of coprological examination with a concentration on parasitic elements. The overall prevalence of intestinal parasites was 62.6%, with the following detected: protozoa: Cystoisospora spp. (9.2%), Sarcocystis spp. (4.5%), Neospora caninum/Hammondia spp. (3.7%), Giardia intestinalis (11.8%); nematoda: Toxocara canis (11.5%), Toxascaris leonina (4.2%), family Ancylostomatidae (38.0%), Trichuris vulpis (21.5%), Capillaria spp. (10.5%); trematoda: Alaria alata (1.6%) and cestodes from the Taeniidae family (1.3%). Factors like age, size and coat length, as well as the way of living, attitude and diet were linked to a significantly higher (p < 0.05) prevalence of intestinal parasites. Based on the results of coprological diagnostics, this research indicates the importance of educating dog owners, conducting routine parasitological tests on their pets and regular deworming strategies.

Epidemiological and molecular updates on hookworm species in dogs from southern Italy

BACKGROUND

The zoonotic hookworms Ancylostoma caninum and Uncinaria stenocephala are widespread soil-transmitted helminths in dogs in Europe. Given the veterinary and public health importance of hookworms in dogs and the recent changes in the molecular epidemiology of some species, there is a need to continuously monitor the epidemiological and molecular prevalence of these parasites also at the "local" level. The present study aimed to update the epidemiological scenario of hookworm infections in both owned and stray dogs in southern Italy and to discriminate between different hookworm species (A. caninum and U. stenocephala) through molecular analyses. For this purpose, a retrospective analysis was performed over 10 years (2011-2021), including a total of 7008 owned dogs and 5642 stray dogs referred to our laboratory for copromicroscopic examinations. Moreover, 72 faecal samples, from dogs naturally infected by hookworms, were used to discriminate between A. caninum and U. stenocephala using two PCR protocols. Prior to molecular analyses, a subsample of 40/72 positive faecal samples was used for morphometric investigations on hookworm eggs.

RESULTS

The results of the ten-year retrospective analysis (2011-2021) showed an overall prevalence of hookworm infection of 9.16%, specifically 5.1% in owned dogs and 14.2% in stray dogs. Logistic regression showed a significant association between positivity to hookworms and the variable "puppies" both in stray (13.84%; OR = 2.4) and owned (7.07%; OR = 2.2) dogs. The results of molecular analyses showed that positivity was confirmed only in 21/72 samples, specifically, 6 samples using protocol A and 19 with protocol B. Sequencing revealed 15 samples positive to U. stenocephala and 6 to A. caninum.

CONCLUSIONS

The findings of this study showed a high prevalence of hookworm infections in dogs in southern Italy, updating the epidemiological scenario of the last decade. Moreover, the results of the study revealed the first identification of hookworm species in dogs in Italy by molecular studies, highlighting that U. stenocephala is more prevalent than A. caninum.

Neglected zoonotic helminthiases in wild canids: new insights from South America

The global threat of neglected tropical diseases (NTDs) constitutes a public health issue in underdeveloped countries. Zoonotic helminthiases are the most common human NTD agents in developing countries in sub-Saharan Africa, Asia, and the Americas, causing a global burden of disease that exceeds that of more recognized infectious diseases such as malaria and tuberculosis. Wild canids are well-known mammals that act as natural reservoirs of zoonotic-relevant helminthiasis worldwide, thus playing a pivotal role in their epidemiology and transmission to humans. Here we evaluate the occurrence of zoonotic gastrointestinal helminths in two Neotropical wild canid species from the Amazonian and Andean regions of Colombia, i.e., the bush dog (Speothos venaticus) and the crab-eating fox (Cerdocyon thous). We recovered tapeworm proglottids from bush dog fecal samples and identified them molecularly as the canine-specific lineage of Dipylidium caninum by using cytochrome c oxidase subunit I (cox1) gene sequences. Moreover, examination of a crab-eating fox during necropsy revealed the presence of non-embryonated eggs of the neglected nematode Lagochilascaris cf. minor, in addition to eggs and gravid proglottids of the cestode Spirometra mansoni. These findings represent the first report of zoonotic-relevant cestodes, i.e., D. caninum ("canine genotype"), S. mansoni, and the nematode L. cf. minor, in bush dogs and crab-eating foxes as final hosts. The occurrence of these zoonotic helminthiases in wild canid species calls for regular monitoring programs to better understand the epidemiology and transmission routes of neglected dipylidiasis, lagochilascariosis, and sparganosis in South America.

Prevalence of Intestinal Parasites, Risk Factors and Zoonotic Aspects in Dog and Cat Populations from Goiás, Brazil

Gastrointestinal diseases caused by parasites are frequently diagnosed in the clinical routine of domestic animals, especially dogs and cats. In general, they trigger factors that can affect human health due to zoonoses. Therefore, this study aims to identify the main intestinal parasites obtained from the fecal samples of dogs and cats in the municipality of Jata, Brazil, and their associated risk factors. Between October 2020 and March 2022, fecal samples were collected from 359 dogs and 55 cats through spontaneous defecation and subsequently subjected to coproparasitological analyses using the Willis fluctuation and Hoffman spontaneous sedimentation techniques. The following parasitic species were identified: Ancylostoma spp., Toxocara spp., Trichuris vulpis, Dipylidium caninum; Giardia spp., Entamoeba spp., Cystoisospora spp., and Platynosomum fastosum. The risk factors associated with parasitism include age, average income of owners, access to garbage, sewage, waste, outdated deworming, and contact with animals. The results demonstrate the need to establish public policies and implement preventive and control measures to reduce the occurrence of parasites in animals and the exposure of humans to pathogenic agents.

Prevalence of Intestinal Parasites in Dogs and Cats from the Kvarner Region in Croatia

Intestinal parasites of dogs and cats may affect their health with a significant zoonotic risk to public health. Therefore, establishing an efficient control program should pass through the determination of the diversity, prevalence, and pathogenicity of those parasites. This study aimed to determine the prevalence of intestinal parasites in dogs and cats and proceed to infection comparisons between young and adult animals. The detection of parasites in fecal samples was determined using flotation and immunofluorescent methods across 320 dogs and 64 cats from the Kvarner region in Croatia. The prevalence was calculated for each detected parasite in its host. Differences in prevalence between young animals and adults were analyzed. Parasites were detected in 32 dogs and 34.4% of cats. In total, 12 different genera were detected; Giardia spp. was the most prevalent parasite in both species, infecting 24.7% and 18.8% of investigated dogs and cats, respectively. Cryptosporidium spp. and Toxocara cati had a prevalence of (18.4%) and (6.3%), respectively. Prevalences of Giardia spp., Cryptosporidium spp., and Cystoisospora spp. were significantly (P < 0.05) higher in puppies compared to adult dogs. Pentatrichomonas hominis (P. hominis) was detected in one puppy. In addition to the first report of P. hominis, a relatively high prevalence of intestinal parasites in dogs and cats in the Kvarner region of Croatia was recorded, posing a potential zoonotic risk.

Epidemiological studies of gastrointestinal parasites infecting dogs in Kwara Central, North Central, Nigeria

Dogs are the most cosmopolitan pets of humans and as such a means of transmitting zoonotic parasites to their owners. This study was designed to investigate the diversity, prevalence, pattern of infection, intensity of infections, and the risk factors associated with gastrointestinal parasites of dogs in Kwara Central, North Central, Nigeria. Three hundred and five clinically healthy dogs were sampled. Faecal samples were subjected to the direct smear, simple faecal centrifugation flotation, formol-ether concentration, and the Modified Ziehl-Neelsen staining techniques. Oocysts/eggs per gram of faeces were counted using the modified McMaster technique. Data were analysed using univariate logistic regression, multivariate logistic regression, and the one-way analysis of variance (ANOVA). A p -value of < 0.05 was considered significant for all analyses. One hundred and sixty-six dogs were positive for at least one species of gastrointestinal parasite, representing 54.43% (95% CI: 44.81 - 59.96) of the sampled population. The study identified Cystoisospora species (15.41%), Cryptosporidium species (25.25%), Ancylostoma species (25.25%), Toxocara canis (19.02%), Strongyloides stercoralis (7.54%), Uncinaria stenocephala (6.89%), and Dipylidium caninum (2.30%) as the gastrointestinal parasites infecting dogs in the study area. Coinfection with more than one species of gastrointestinal parasites was a common finding in dogs. The intensity of Cystoisospora spp. among infected dogs ranged between 40 and 980 oocysts per gram of faeces, while that of helminth parasites was 40 - 1560 eggs per gram of faeces. Age, sex, breeds, body condition score, presence of ticks on dogs, the purpose of keeping dog(s), types of housing, types of feed consumed, vaccination status, and treatment with antiparasitics were predators associated with the prevalence and intensity of gastrointestinal parasites infections. Due to the zoonotic nature of most of the encountered gastrointestinal parasites, there is need for regular antiparasitic treatment, proper dog management, and adequate personal hygiene to prevent zoonosis.

Gastrointestinal parasites in young dogs and risk factors associated with infection

Young dogs are particularly susceptible to infections with endoparasites. The occurrence of endoparasites was investigated in young dogs from Central Germany between July 2020 and July 2022. In total, 386 fecal samples originating from 171 dogs were examined for the prevalence of endoparasites using a combined flotation- and sedimentation technique and conventional PCR. Overall, in 41.2% (159/386) of the examined samples, endoparasites were detected. The most frequently occurring endoparasites were Giardia duodenalis (29%), Cryptosporidium spp. (9.1%), Cystoisospora spp. (7.3%), and Toxocara canis (6%). Sequencing of G. duodenalis positive samples showed that most infections belonged to the host-specific assemblages C (38.4% (43/112)) and D (35.7% (40/112)). The zoonotic assemblage A was identified in 8% (9/112) of the samples. Moreover, mixed infections were observed as follows: C/D in 5 (4.5%), D/A in 4 (3.6%), and C/A in 3 (2.7%) samples. All assemblage A infections were assigned to the potentially zoonotic subassemblage AI. Co-infections of G. duodenalis and Cryptosporidium spp. were observed in 3.1% (12/386) of the samples. Analyzing several host factors for their potential association with endoparasitic infection, the origin of dogs, as well as the living environment were identified as the main risk factors for infection with endoparasites. Overall, this study shows a high infection rate with endoparasites, especially G. duodenalis, in young dogs from Germany. The results of this study contribute to further insight into the distribution and potential risk factors associated with endoparasitic infections, as well as the zoonotic potential these parasites may present.

Dipylidium caninum in the twenty-first century: epidemiological studies and reported cases in companion animals and humans

Background

Dipilidiosis is a parasitic disease caused by the tapeworm Dipylidium caninum. Fleas and, less frequently, lice act as an intermediate host, and their ingestion is required for infection to occur. While the disease mainly affects domestic and wild carnivores, it is also considered a zoonotic disease, with most human cases reported in children. Dipylidium caninum is considered to be the most common tapeworm infesting companion animals, but dipilidosis in humans is rare. The aims of this review were to improve current understanding of the epidemiology of this parasitosis and its management by the medical and veterinary community.

Methods

A comprehensive review of the published literature during the last 21 years (2000–2021) on the epidemiology, clinical features, diagnosis, treatment and prevention measures of D. caninum infection and dipilidiosis in companion animals and humans was conducted.

Results

Using predefined eligibility criteria for a search of the published literature, we retrieved and screened 280 publications. Of these, 161 (141 epidemiological studies, 20 case reports [16 human cases]) were considered for inclusion in this review. This parasitosis is present worldwide; however, despite being the most frequent cestode infection in animals, it is often underdiagnosed using common coprological techniques. Its diagnosis in humans has also proved challenging, being frequently confused with pinworm infection, leading to inappropriate treatment and to the persistence of the disease over time. Prevention measures include control of ectoparasites in animals and the environment, as well as regular deworming of animals, most commonly with praziquantel.

Conclusions

The diagnosis of dipilidiosis remains challenging in both animals and humans, primarily due to the low sensitivity of the diagnostic methods currently available and a lack of knowledge of the morphological characteristics of the parasite. Although treatment with the appropriate anti-cestode compounds is well tolerated and results in resolution of the infection, indiscriminate use of these compounds may predispose to an increase in resistance. Given the worldwide distribution of this parasite, it is essential to act on several fronts, with a focus on health education for children and animal owners and the control of intermediate hosts, both in animals and in the surrounding environment.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-022-05243-5.

Deworming Schemes’ Efficacy for Adult Dogs with Mixed Gastro-Intestinal Helminthoses

Mixed gastrointestinal helminthoses, which combines Toxocara canis, Trichuris (T.) vulpis, Toxascaris leoninа, Uncinaria stenocephala, Ancylostoma caninum, and Dipylidium caninum in various combinations, are very common pets’ problems worldwide. It is unlikely necessary to choose between 100 % efficiency and for the patient’s body to heal the infected animals safely. The present work aims to develop an affordable scheme for adult dogs’ deworming, which will create a minimum load on the body due to the low drugs’ toxicity. Mixed breed dogs, 1—5 years old, representing both sexes, spontaneously infected with T. vulpis (100 % prevalence) in combination with other gastrointestinal helminths (from 12.7 to 45.1 %) were selected for study. Regimens combining Caniquantel® Plus (fenbendazole + praziquantel) and fenbendazole with a 24-hour interval were tested. After a single treatment of experimental animals with Caniquantel® Plus, no helminth eggs were detected in their faeces after three days, except for T. vulpis. Seven days after the start of the experiment, the intensity of infection of this nematode decreased by only 22.0 % (P < 0.001). Bodies and fragments of dead helminths were found in faeces 1—4 days after de-worming, with T. vulpis isolated only in 2 days in small quantities (4.54 ± 0.21 specimens per 100 g of faeces). Two-stage deworming with Caniquantel® Plus and fenbendazole after 24 hours resulted in 100 % efficiency against eggs of all parasites after five days. Helminths’ bodies stopped excreting after four days, and T. vulpis was detected within three days in substantive quantities (from 10.03 ± 0.45 to 36.8 ± 1.2 specimens per 100 g of faeces).

Two trichinellosis outbreaks in Serbia – challenging diagnosis due to a potential co-infection with Toxocara spp

In Serbia, in most cases, small family outbreaks of trichinellosis occur due to the consumption of untested infected meat from domestic pigs that are raised and slaughtered in the backyards of small individual farms. The aim of this study is to present data regarding 24 patients involved in two outbreaks that occurred in two neighbouring districts in Serbia during a closely related period of time in August 2014. The source of infection in the first outbreak was undercooked pork, while raw pork sausages caused the second outbreak. Meat samples and sausages were Trichinella spp. positive by artificial digestion. With the aim to obtain a second opinion and validate the serological findings discovered at the Public Health Institute Nis, all samples were sent to the National Reference Laboratory for Trichinellosis, INEP. Serodiagnosis showed that 21 persons were positive (87.5%) and three (12.5%) were negative for anti-Trichinella antibodies, while 15 patients fulfilled the trichinellosis case definition. Western blot analysis (using an epitope unique for the muscle larvae stage of the Trichinella genus) confirmed the diagnosis of trichinellosis in five patients. Six patients also had specific antibodies against Toxocara canis (T. canis). Due to the fact that in endemic foci in Serbia there is the presence of Trichinella spiralis and T. canis and that these two infections could be asymptomatic, we consider that trichinellosis cases were irrefutably proven. The dilemma about the existence of co-infection with T. canis remained open due to the lack of clinical findings.