Prevalence and zoonotic potential of canine hookworms in Malaysia

Emerging zoonotic diseases in Southeast Asia in the period 2011-2022: a systematic literature review

As COVID-19 has shown, pandemics and outbreaks of emerging infections such as Zika, Nipah, monkeypox and antimicrobial-resistant pathogens, especially emerging zoonotic diseases, continue to occur and may even be increasing in Southeast Asia. In addition, these infections often result from environmental changes and human behaviour. Overall, public health surveillance to identify gaps in the literature and early warning signs are essential in this region. A systematic review investigated the prevalence of emerging zoonotic diseases over 11 years from 2011 to 2022 in Southeast Asia to understand the status of emerging zoonotic diseases, as well as to provide necessary actions for disease control and prevention in the region. During the 2011-2022 period, studies on pigs, poultry, ruminants, companion animals and wildlife in Southeast Asia were reviewed thoroughly to assess the quality of reporting items for inclusion in the systematic review. The review was performed on 26 studies of pigs, 6 studies of poultry, 21 studies of ruminants, 28 studies of companion animals and 25 studies of wildlife in Southeast Asia, which provide a snapshot of the prevalence of the emerging zoonotic disease across the country. The findings from the review showed that emerging zoonotic diseases were prevalent across the region and identified a few zoonotic diseases associated with poultry, mainly stemming from Cambodia and Vietnam, as high priority in Southeast Asia.Clinical relevance: Appropriate prevention and control measures should be taken to mitigate the emerging zoonotic diseases in Southeast Asia.

Effect of Soil Temperature on Canine Soil-Transmitted Nematodes in Kandy District with the First Record of Hookworm, Ancylostoma tubaeforme from Sri Lanka

PURPOSE

Soil-transmitted nematodes (STNs) are widespread in tropical and subtropical regions, particularly where the communities are socio-economically challenged. We investigated the effect of soil temperature on the prevalence and intensity of STN infection in free-roaming dogs.

METHODS

Fresh faecal samples collected from free-roaming dogs in Digana and Pussellawa town areas in the Kandy District, Sri Lanka, were microscopically analysed for canine STNs. Soil temperature was measured at each sampling site. Highly prevalent canine hookworm Ancylostoma, was further studied using PCR and sequencing, followed by phylogenetic analysis.

RESULTS

The soil temperature ranged between 28 and 31 °C (mean = 29.79 °C) and 18-21 °C (mean = 19.52 °C) in Digana and Pussellawa, respectively, showing a significant difference in the two sites (Students t-test t = 1.68, p < 0.0001). Of the total 44 dogs sampled, 41 (93.2%) were positive for STNs. During microscopic analysis, five nematodes: Ancylostoma spp., Capillaria sp., Strongyloides sp., Toxocara canis, and Trichuris sp., were identified. Ancylostoma species (93.2%) were the most prevalent, followed by Strongyloides sp. (22.7%) and Toxocara canis (15.9%). Infection prevalence of Strongyloides sp. was higher in Digana (40.9%) compared to that in Pussellawa (4.5%; Chi-square test, χ2 = 8.28, p = 0.004) and also the infection intensity from Digana (EPG = 8.02 ± 20.2) compared to that from Pussellawa (0.45 ± 2.1; Mann Whitney U test, p = 0.006). Amplicons (ITS1-5.8S-ITS2) of the expected size for A. caninum, and A. tubaeforme were produced. An A. caninum sequence reported here (OQ101719) illustrated the highest similarity of 99.2% to one of the local sequences (MZ707153) upon pairwise comparison.

CONCLUSION

Digana, with a higher soil temperature than Pussellawa, had a significantly higher prevalence and infection intensity, particularly Strongyloides sp. This study also signifies the first molecular identification of hookworm species A. tubaeforme in Sri Lanka.

Molecular identification and genetic diversity of zoonotic hookworm infections in domestic dogs from northeastern, Thailand

Hookworm infections remain a significant public health concern in tropical and subtropical regions, including Thailand. This study investigated the species and genetic diversity of hookworm infections in domestic dogs from northeastern Thailand. The molecular analysis focused on amplifying and sequencing specific regions of ribosomal RNA genes (ITS1-5.8S-ITS2 region) and the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene in hookworm larvae recovered from 21 domestic dog stool samples. Among 21 larvae (one larva per infected dog) analyzed, 14 had sequences identical to Ancylostoma caninum, and 7 showed sequences almost identical to Ancylostoma ceylanicum. Phylogenetic analysis of cox1 sequences placed A. caninum and A. ceylanicum in separate clades. The median-joining network of A. caninum cox1 sequences from Thailand showed high haplotype diversity and belonged to the same cluster as sequences from Australia while forming separate clusters from those of A. caninum samples from the USA. The available published A. ceylanicum cox1 sequences (n = 33), in combination with seven sequences in the present study, represented 15 haplotypes distributed among three clusters. Interestingly, A. ceylanicum sequences from dogs and humans shared the same haplotypes. These findings are crucial for recognizing the potential for zoonotic transmission, highlighting the necessity for targeted control measures, and increasing awareness among pet owners and healthcare professionals to mitigate the risk of hookworm transmission to humans.

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.

Molecular evidence of hookworms in public environment of Bangladesh

Accurate diagnosis by precise identification of causative agents is essential for the effectiveness of any control interventions. Despite high zoonotic potential, available literature on hookworms in Bangladesh is still scarce and nonspecific. The objective of this study was to determine the occurrence of hookworms in public locations across northeastern Bangladesh (Sylhet metropolitan area) using integrated parasitological and molecular assays. A total of 130 samples (80 soil and 50 environmental canine feces) were collected and examined using modified flotation technique and formalin-ether sedimentation methods. Modified plate culture was used to isolate larvae. The identification was made based on morphometric features and confirmed by amplifying the ITS region of the nuclear rDNA. Overall, 66.2% (86/130) of examined samples were positive for hookworms infection. Characteristic eggs (61-68 × 29-37 μm) and/or larvae of hookworms were observed in 73.8% (59/80) soils and 54.0% (27/50) environmental fecal samples. Rhabditiform larvae (0.48-0.54 × 0.04-0.07 mm) were observed in cultured samples. Genetic analysis of rDNA sequences revealed the presence of Ancylostoma caninum and Ancylostoma ceylanicum. In this study, hookworms' contamination of the public environment was substantial. To the best of our knowledge, this is the first molecular proof of A. caninum and A. ceylanicum observed in urban public environment in Bangladesh.

Modeling the effectiveness of One Health interventions against the zoonotic hookworm Ancylostoma ceylanicum

Hookworm disease is a major global public health concern, annually affecting 500-700 million of the world's poorest people. The World Health Organization is targeting the elimination of hookworm as a public health problem by 2030 using a strategy of mass drug administration (MDA) to at-risk human populations. However, in Southeast Asia and the Pacific the zoonotic hookworm species, Ancylostoma ceylanicum, is endemic in dogs and commonly infects people. This presents a potential impediment to the effectiveness of MDA that targets only humans. Here, we develop a novel multi-host (dog and human) transmission model of A. ceylanicum and compare the effectiveness of human-only and "One Health" (human plus dog) MDA strategies under a range of eco-epidemiological assumptions. We show that One Health interventions-targeting both dogs and humans-could suppress prevalence in humans to ≤ 1% by the end of 2030, even with only modest coverage (25-50%) of the animal reservoir. With increasing coverage, One Health interventions may even interrupt transmission. We discuss key unresolved questions on the eco-epidemiology of A. ceylanicum, the challenges of delivering MDA to animal reservoirs, and the growing importance of One Health interventions to human public health.

Prevalence of intestinal parasites in animal hosts and potential implications to animal and human health in Edo, Nigeria

BACKGROUND

Intestinal parasites in livestock cause huge economic setbacks. Moreover, these parasites can threaten human health when also present in companion animals.

OBJECTIVES

The study examined the prevalence and burden of intestinal parasites among roaming/migrating animals (goats, sheep, cattle, and dogs) to provide insights into the risk of potential human parasitic infections.

METHODS

A total of 1,741 fecal samples from goats (n = 920), sheep (n = 335), cattle (n = 230) and dogs (n = 256) were obtained randomly across 18 local government areas in Edo State, Nigeria. The parasite samples were recovered and identified under a microscope. Molecular tools were used to identify Toxocara spp.

RESULTS

Eighteen different parasites were isolated. Among the different groups of parasites observed, nematodes occurred the most, followed by protozoans. Among nematodes, Haemonchus was most prevalent in goats (28.04%) and sheep (29.85%), while Strongyloides (10.86%) and Bunostomum (8.69%) were relatively high in cattle. Strongyloides (3.9%), hookworm (3.9%), and Toxocara (3.12%) were the predominant parasites in dogs. For protozoan parasites, Eimeria was most common in all 4 animal hosts. Several goats (2.39%) and sheep (2.38%) tested positive for Fasciola spp. Molecular analysis confirmed Toxocara canis in dogs for the first time in Nigeria.

CONCLUSIONS

The major parasites recovered from these roaming/migrating animals have zoonotic potentials that can threaten human health.

Helminth infections in dogs in Phu Tho Province, northern Vietnam

Helminths are among the most-commonly encountered disease-causing agents in dogs all over the world, including Vietnam. A cross-sectional survey was carried out between March and December 2019 in four dog slaughter-slabs in Yen Lap District, Phu Tho Province, northern Vietnam, aiming to reveal the occurrence of gastrointestinal helminths in dogs. Worms were collected from 350 dog samples and identified by morphological techniques followed by molecular methods for tapeworms and hookworms. Nine species, including Taenia hydatigena, Spirometra erinaceieuropaei, Dipylidium caninum, Spirocerca lupi, Ancylostoma ceylanicum, Ancylostoma caninum, Toxocara canis, Toxascaris leonina and Trichuris vulpis, were found to occur in this area. Infection with at least one worm species was found in 272 dogs (77.7%; 95% Wilson score CI: 73.1-81.8%). The most common species was A. ceylanicum, with a prevalence of 45.1% (95% Wilson score CI: 40.0-50.4%) while T. hydatigena had a very low prevalence of 0.3% (95% Exact CI: 0.0-1.6%). Co-infection with hookworms and D. caninum was common. Five of the recovered helminth species have a zoonotic potential. Control of these parasites is necessary in order to protect human and animal health.

Prevalence of hookworm infections among stray dogs and molecular identification of hookworm species for the first time in Bangladesh

Hookworms are the most common and voracious blood-sucking parasites of the small intestines of mammalian hosts such as dogs, cats, ruminants and humans. Canine hookworms are endemic in the Southeast Asian countries including Bangladesh. There is scarcity of information on the prevalence of hookworms of stray dogs in Bangladesh. The present study determined the prevalence of canine hookworms using fecal examination followed by morphometric and molecular identification. Fecal samples were collected from 320 stray dogs living in rural areas of Mymensingh district (Gauripur upazila, Mymensingh sadar upazila and Tarakanda upazila) and hookworm eggs were identified using the flotation techniques. The overall prevalence of hookworm was 79.1% through microscopic examination. Estimated fecal prevalence was higher in Gauripur upazila (89.7%) followed by Mymensingh sadar upazila (84.8%) and Tarakanda upazila (53.2%). Five hookworm species were identified based on the morphometric examination, namely, Ancylostoma caninum, Ancylostoma ceylanicum, Ancylostoma tubaeforme, Ancylostoma braziliense and Ancylostoma duodenale, respectively. Polymerase Chain Reaction (PCR) was performed with the genomic DNA by targeting the 5.8S rRNA (~ 404 bp) and Cytochrome oxidase-1 (Cox 1, ~ 450 bp) and confirmed the identification for the first time in Bangladesh. This study reveals that stray dogs may act as reservoir hosts of human hookworm infection. Further detail molecular study is warranted to explore the genetic diversity of hookworms that infect both dogs and human in Bangladesh.

A Case of Zoonotic Ancylostoma ceylanicum Infection in a Suburban Area of Selangor, Malaysia

INTRODUCTION

The animal hookworm, Ancylostoma ceylanicum, is a dominant hookworm species of dogs and cats. However, it has increasingly been found infecting humans in Southeast Asia.

PURPOSE

We report an autochthonous case of A. ceylanicum in a suburban area of Selangor, Malaysia. A 66-year-old Indian lady who is an avid gardener presented with chronic diarrhea of 4 months' duration.

METHODS

The patient was examined clinically and colonoscopy was performed. Adult parasites obtained via colonoscopy were subjected to microscopy and molecular investigations.

RESULTS

Clinical examinations were unremarkable, and blood investigation revealed normochromic normocytic anemia. Stool occult blood was positive but negative for ova, cyst and adult parasites. Colonoscopy performed showed multiple diverticulae and worm infestation from the terminal ileum to sigmoid colon. Morphological examination on the adult worms showed the specific characteristics of Ancylostoma species. Molecular investigations further confirmed the nematode as Ancylostoma ceylanicum. She was treated with albendazole 400 mg daily for 3 days with symptomatic improvements sustained 3 months later. It is suspected that the patient had ingested or contacted soil contaminated with filariform larvae while gardening.

CONCLUSION

Information on the A. ceylanicum infection in humans, especially in urban and suburban areas, is limited, necessitating further epidemiological and clinical studies.

Prevalence and distribution of soil-transmitted helminth infection in free-roaming dogs in Bali Province, Indonesia

BACKGROUND AND AIM

Several free-roaming dogs can be easily found in the public areas of Bali. They go out in search of foods and friends and defecate everywhere. In general, these groups of dogs do not receive good healthcare from their owners and are generally threatened by some disease-causing organisms, especially helminths. This study was conducted to identify and measure the prevalence of soil-transmitted helminths (STHs) that cause infection in free-roaming dogs in Bali Province, Indonesia.

MATERIALS AND METHODS

A total of 1611 fresh dog fecal samples were collected from all areas of Bali Province and subjected to qualitative fecal examination using flotation techniques to obtain STH eggs.

RESULTS

The incidence of STHs in free-roaming dogs was 38.36%. However, three types of STHs were identified, including Ancylostoma spp., Ascaris spp., and Trichuris spp. Ancylostoma spp. had the highest prevalence of 37.8%, followed by Ascaris spp. and Trichuris spp. at 6.02% and 0.87%, respectively. Multiple infections of these worms were also recorded. The polyparasitism prevalence of Ancylostoma spp. and Ascaris spp. was 3.85%, followed by that of Ancylostoma spp. and Trichuris spp. at 0.5% and that of Ascaris spp. and Trichuris spp. at 0.06%. There were no altitude-wise differences in the prevalence of STH infection.

CONCLUSION

The prevalence of STHs was high in free-roaming dogs. This finding necessitates more serious attention as it affects both animal and public health.

Ancylostoma ceylanicum: The Neglected Zoonotic Parasite of Community Dogs in Thailand and Its Genetic Diversity among Asian Countries

Ancylostoma ceylanicum is a zoonotic helminth that is commonly found in domestic dogs and cats throughout Asia but is largely neglected in many countries. This study aimed to confirm the species of hookworm in dogs and soil environments and investigate the evolutionary analyses of A. ceylanicum among Thai and Asian populations. In a total of 299 dog fecal samples and 212 soil samples from 53 temples, the prevalence rates of hookworm infection by microscopic examination were 26.4% (79/299) and 10.4% (22/212) in dog and soil samples, respectively. A PCR-RFLP targeting the ITS region was then utilized to identify the hookworm species. In dogs, A. ceylanicum was the main hookworm species, and the rates of A. ceylanicum and A. caninum infections were 96.6% and 3.5%, respectively. The genetic characterization and diversity indices of the A. ceylanicumcox1 gene among Thai and Asian populations were evaluated. Nine haplotypes were identified from Thai A. ceylanicum, in which the haplotype diversity and the nucleotide diversity were 0.4436 and 0.0036, respectively. The highest nucleotide diversity of Chinese A. ceylanicum populations suggested that it could be the ancestor of the populations. Pairwise fixation indices indicated that Thai A. ceylanicum was closely related to the Malaysian population, suggesting a gene flow between these populations. The temples with hookworm-positive dogs were associated with the presence of hookworm-contaminated soil, as these levels showed an approximately four-fold increase compared with those in temples with hookworm-negative dogs (OR = 4.38, 95% CI: 1.55-12.37). Interestingly, the genotypes of A. ceylanicum in the contaminating soil and infecting dogs were identical. Therefore, increased awareness and concern from the wider public communities with regard to the responsibility of temples and municipal offices to provide proper deworming programs to community dogs should be strongly endorsed to reduce the risk of the transmission of this zoonotic disease. In addition, parasitic examination and treatment should be strongly implemented before dogs are imported and exported worldwide.

Epidemiological survey on intestinal helminths of stray dogs in Guimarães, Portugal

The new legislative framework on Animal Welfare brought increased responsibilities to municipal shelters, in particular in the collection of stray dogs, their sterilization and future adoption. These centers quickly became overcrowded, leading to high parasitism environmental contamination, to the easy spread of parasitic infections and to increased risks to public health. The prevalence of intestinal parasites was evaluated by examination of dog faecal sample, in the municipal control animal centre of Guimarães (north Portugal), identifying risk factors and transmission to man. The overall prevalence of gastrointestinal helminths was 57.2% (95% confidence interval 41.3–71.9%) and observed helminths of the gastrointestinal tract were recorded: Ancylostoma caninum (33%), Toxocara canis (29%), Dipylidium caninum (6%), Capillaria spp. (3%), Trichuris vulpis (1.66%). It is important to point out that young dogs were significantly infected more frequently (p ≤ 0.1) than non-sterilized females and the higher occurrence of nematode infection occurred at the new arrival of stray dogs, in the third collection. With impact on public health, the higher prevalence (p ≤ 0.1) of T. canis in young dogs suggests the existence of real risk for human infection and demonstrate the necessity for a parasite control programme reinforcement at the municipal dog shelter.

High-throughput multiplex qPCRs for the surveillance of zoonotic species of canine hookworms

The canine hookworms Ancylostoma braziliense, Ancylostoma ceylanicum, Ancylostoma caninum and Uncinaria stenocephala are not only capable of producing morbidity and mortality in dogs but are also neglected tropical zoonoses. Each hookworm species differs considerably in its geographical distribution, life cycle, biology, pathogenic impacts on both canine and human hosts, zoonotic potential, and response to treatment with anthelminthics. Here we describe the development and validation of two Taq-Man based multiplex PCR assays capable of detecting and differentiating all four canine hookworm species in faeces of naturally infected dogs. The analytical sensitivity of both assays was assessed using 10-fold serial dilutions of synthetic gene block fragments containing individual sequence targets of each hookworm species. The sensitivity of the assays and ability to detect mixed species infections were compared to a conventional PCR-Restriction Fragment Length Polymorphism based-approach when applied to laboratory and field samples from endemic areas. The qPCRs detected at least one species of hookworms in 82.4% of PCR-RFLP-negative but microscopy-positive samples. The qPCRs detected an additional 68% mixed infections with different species of canine hookworms, and additional single species infection with A. caninum (47%), U. stenocephala (33%) and A. ceylanicum (0.02%) that were missed by PCR-RFLP. These multiplex qPCR assays will assist field based epidemiological surveillance studies towards an accurate and sensitive monitoring of canine hookworm infections in dogs, to inform their species-specific zoonotic risks to populations living in endemic areas, globally.

Semi-domesticated dogs as a potential reservoir for zoonotic hookworms in Bangkok, Thailand

Background and Aim:

Hookworms are parasitic nematodes that live in the small intestine of their mammalian hosts including humans, dogs, and cats. This study was conducted to determine the prevalence and perform genetic characterization of hookworms using molecular techniques and to elucidate the risk factors associated with hookworm infections among semi-domesticated dogs residing in temples in the Bangkok Metropolitan Area, Thailand.

Materials and Methods:

A total of 500 fecal samples were collected from semi-domesticated dogs from 91 temples in 48 districts of Bangkok. DNA was extracted and screened using internal transcribed spacer polymerase chain reaction-restriction fragment length polymorphism. In addition, samples positive for Ancylostoma ceylanicum were further characterized at the haplotype level based on the analysis of the mitochondrial cytochrome oxidase-1 gene (cox1).

Results:

The prevalence of hookworm infections in semi-domesticated dogs was 6.2% (31/500). Hookworm infections were detected in temple-community dogs in 12 of 48 districts (25.0%), with Bang Khen and Lak Si districts having the highest proportion of infected dogs (22.6%). Regarding molecular characterization of hookworm species, 21 positive samples (67.74%) were infected with A. ceylanicum and 10 (32.26%) with Ancylostoma caninum. Characterization of cox1 in A. ceylanicum isolates revealed the presence of a mixture of human and dog isolates.

Conclusion:

Semi-domesticated dogs act as a potential source of hookworm infections for human and animal populations in Bangkok, Thailand.

Ancylostoma ceylanicum Hookworm in Myanmar Refugees, Thailand, 2012-2015

This hookworm, uncommonly found in humans, has a higher cure rate than that for Necator americanus hookworm.

During 2012–2015, US-bound refugees living in Myanmar–Thailand border camps (n = 1,839) were surveyed for hookworm infection and treatment response by using quantitative PCR. Samples were collected at 3 time points: after each of 2 treatments with albendazole and after resettlement in the United States. Baseline prevalence of Necator americanus hookworm was 25.4%, Ancylostoma duodenale 0%, and Ancylostoma ceylanicum (a zoonosis) 5.4%. Compared with N. americanus prevalence, A. ceylanicum hookworm prevalence peaked in younger age groups, and blood eosinophil concentrations during A. ceylanicum infection were higher than those for N. americanus infection. Female sex was associated with a lower risk for either hookworm infection. Cure rates after 1 dose of albendazole were greater for A. ceylanicum (93.3%) than N. americanus (65.9%) hookworm (p<0.001). Lower N. americanus hookworm cure rates were unrelated to β-tubulin single-nucleotide polymorphisms at codons 200 or 167. A. ceylanicum hookworm infection might be more common in humans than previously recognized.

Molecular identification of zoonotic hookworms in dogs from four counties of Kenya

All canine hookworms are known to be zoonotic, causing infections ranging from transient skin irritations to prolonged ‘creeping eruptions’, eosinophilic enteritis and even patent intestinal infections. There is little information on canine hookworm species and their public health significance in sub-Saharan Africa. This study determined the prevalence and species of hookworms in dogs from different climatic zones of Kenya. Dog faecal samples were collected from the environment, and hookworm eggs were isolated by zinc chloride flotation and subjected to DNA extraction. Polymerase chain reaction (PCR) assays targeting the internal transcribed spacer (ITS) 1 and 2, 5.8S and 28S ribosomal RNA ofAncylostomaspp. andUncinaria stenocephalawere performed, and hookworm species were identified by PCR-restriction fragment length polymorphism (RFLP) or DNA sequencing. Hookworm eggs were detected by microscopy in 490/1621 (30.23%, 95% CI 28.01–32.54) faecal samples. Estimates of faecal prevalence were high in counties receiving higher rainfall (Narok 46.80%, Meru 44.88%) and low in those with a more arid climate (Isiolo 19.73%, Turkana 11.83%). In a subset of 70 faecal samples,Ancylostoma caninum(n = 59) was the most common species, followed byA. braziliense(n = 10) andA.cf.duodenale(n = 1). This study reports for the first time the detection ofA.cf.duodenalein dog faeces and zoonotic hookworm species in Kenyan dogs. These findings emphasize the need for control measures such as enforcing laws for restraining stray dogs, regular deworming of dogs, and public health awareness programmes aimed at informing communities on outdoor use of footwear.

The Prevalence of Intestinal Helminths in Free-Ranging Canids of Mazandaran, Northern Iran

BACKGROUND

The purpose of this study was to investigate the current knowledge on the epidemiology of importance zoonotic parasitic diseases in free-ranging canids of Mazandaran, north of Iran.

METHODS

Overall, 63 small intestinal samples of animals (20 stray dogs and 43 golden jackals) were collected from April 2017 to May 2018. The intestine contents were studied to detect and identify helminth infections. Additionally, 274 fecal samples (130 dogs, 35 fox, 90 golden jackal and 19 wolf) were examined by Sheather's flotation method for detection of Taenia eggs.

RESULTS

Sixty (95.2%) animals were infected with at least one species of intestinal helminth. the intestinal helminths were found in dogs and golden jackals included: Dipylidium caninum (25.3%), Uncinaria stenocephala (52.3%), Ancylostoma caninum (41.2%), Mesocestoides spp. (33.3%) and Toxocara canis (14.2%). In fecal examination, 2.5% of samples contained Taenia eggs, and through a species-specific PCR, 1.09% of these samples were confirmed positive for Echinococcus granulosus.

CONCLUSION

There is a high prevalence and clear risks of zoonotic helminths in free-ranging carnivores in Mazandaran province, north of Iran. Therefore, understanding the epidemiology of zoonotic parasite infection is useful for health care access both domestic animals and humans health.

Gastrointestinal Parasites in Shelter Dogs: Occurrence, Pathology, Treatment and Risk to Shelter Workers

Dogs entering shelters can carry gastrointestinal parasites that may pose serious risks to other animals, shelter staff and visitors. Shelters provide an environment that could facilitate the spread of parasitic infections between animals. Nematodes and protozoa that transmit through ingestion or skin penetration are major enteric parasites of concern in shelter settings. Ancylostoma spp., Uncinaria stenocephala, Toxocara canis, Toxascaris leonina, Trichuris vulpis and Dipylidium caninum are the major helminths while Giardia, Cryptosporidium, Isospora spp. and Sarcocystis spp. are the most prevalent protozoan parasites in shelter dogs. The prevalence of gastrointestinal parasites in shelter dogs is typically higher than in owned dogs. A range of cost-effective drugs is available for prevention and control of helminths in shelters, notably fenbendazole, pyrantel, oxantel, and praziquantel. Parasiticide options for protozoan parasites are often cost-prohibitive or limited by a lack of veterinary registration for use in dogs. Environmental control measures reliant upon hygiene and facility management are therefore a mainstay for control and prevention of protozoan parasites in shelters. This philosophy should also extend to helminth control, as integrated parasite control strategies can allow anthelmintics to be used more sparingly and judiciously. The purpose of this article is to comprehensively review the current knowledge on the prevalence of gastrointestinal parasites most commonly found in dogs in shelters, canvass recommended treatment programs in shelter dogs, and to explore the likelihood that parasiticide resistance might emerge in a shelter environment.

Molecular identification of zoonotic hookworm species in dog faeces from Tanzania

The presence and distribution of various species of canine hookworms in Africa are poorly known. The main objective of this study, therefore, was to identify the hookworm species present in canine faecal samples from Morogoro, Tanzania, using molecular techniques. Faecal samples from 160 local dogs were collected and hookworm positive samples processed to recover larvae for further molecular characterization. DNA was extracted from pools of larvae from individual samples (n = 66), which were analysed subsequently using two different molecular approaches, polymerase chain reaction-linked restriction fragment length polymorphism (PCR-RFLP) and species-specific PCR coupled with Sanger sequencing. The PCR-RFLP technique detected only the presence of the ubiquitous Ancylostoma caninum in the 66 samples. However, by species-specific PCR coupled with Sanger sequencing we identified ten samples with A. braziliense, two with Uncinaria stenocephala and five with A. ceylanicum. Thus, all four known species of canine hookworms were identified in Morogoro, Tanzania. To our knowledge this is the first report of the detection of the presence of U. stenocephala and A. ceylanicum in Africa using molecular techniques. In addition to their veterinary importance, canine hookworms have zoonotic potential and are of public health concern.

Soil-Transmitted Helminths in Tropical Australia and Asia

Soil-transmitted helminths (STH) infect 2 billion people worldwide including significant numbers in South-East Asia (SEA). In Australia, STH are of less concern; however, indigenous communities are endemic for STH, including Strongyloides stercoralis, as well as for serious clinical infections due to other helminths such as Toxocara spp. The zoonotic hookworm Ancylostoma ceylanicum is also present in Australia and SEA, and may contribute to human infections particularly among pet owners. High human immigration rates to Australia from SEA, which is highly endemic for STH Strongyloides and Toxocara, has resulted in a high prevalence of these helminthic infections in immigrant communities, particularly since such individuals are not screened for worm infections upon entry. In this review, we consider the current state of STH infections in Australia and SEA.

Prevalence and Molecular Aspects of Human Hookworms in Guilan Province, Northern Iran

BACKGROUND

Hookworm infection is one of the important Neglected Tropical Diseases (NTD) in the world. It was previously more prevalent in the northern and southern parts of Iran with a prevalence rate higher than 40% in some endemic regions; nevertheless, the infection rate has decreased to less than 1%. This study aimed to determine prevalence and molecular aspects of hookworm infections in rural inhabitants of Fouman County, Guilan Province, northern Iran.

METHODS

This cross-sectional study was performed in 31 villages of Fouman district in Guilan Province, northern Iran during 2015-2016. Stool samples were collected from 1500 rural inhabitants and examined by formalin ethyl-acetate concentration as well as agar plate culture techniques. After treatment with albendazole, adult hookworms were isolated. Following DNA extraction, PCR amplification of ITS2-rDNA region was performed and the product was sequenced, followed by genetic variation analysis.

RESULTS

Of 1500 samples, one case was morphologically diagnosed as N. americanus. In addition, molecular characterization verified the presence of N. americanus, showing more than 95% similarity with sequences of N. americanus present in GenBank. The patient showed no clinical symptoms and a mild hypereosinophilia was the only laboratory finding observed.

CONCLUSION

A reduced prevalence of human hookworms was demonstrated within Guilan Province located in north of Iran. The N. americanus originated from Guilan had a high homology with the isolates found in Japan, Laos, Malaysia, and Australia.

First Molecular Identifications of Necator americanus and Ancylostoma ceylanicum Infecting Rural Communities in Lower Myanmar

Hookworms are enteric parasitic roundworms infecting an estimated 400 million persons worldwide. Herein, we provide the first molecular identifications of human hookworms from certain parts of rural Lower Myanmar. DNA was extracted from hookworm-positive stool samples, as determined by microscopy. DNA sequences of the partial internal transcribed spacer 1, full length 5.8S gene, and partial internal transcribed spacer 2 were determined and compared with available hookworm sequences from public databases. Of the 11 polymerase chain reaction-positive samples, eight (Bago Region, N = 4; Mon State, N = 4) yielded sequences with high similarity to those of Necator americanus A further three sequences (Mon State, N = 2; Bago Region, N = 1) showed high similarity with those of Ancylostoma ceylanicum The latter is primarily a parasite of dogs and represents a zoonosis. Given that different species of hookworms exhibit different epidemiological and biological characteristics, accurate identification is essential for the planning and execution of effective control programs for hookworm infections.

Molecular Modeling and Structural Analysis of Arylesterase of Ancylostoma Duodenale

Parasitic worm infection of humans is one of the most commonly prevalent helminth infection that has imposed great impact on society and public health in the developing world. The two species of hookworm, namely Ancylostoma duodenale and Necator americanus may be primarily responsible for causing parasitic infections in human beings. The highly prevalent areas for Ancylostoma duodenale infections are mainly India, Middle East, Australia, northern Africa and other parts of the world. The serum arylesterases/paraoxonases are family of enzymes that is involved in the hydrolysis of a number of organophosphorus insecticides to the nontoxic products. The participation of the enzymes in the breakdown of a variety of organophosphate substrates that is generally made up of paraoxon and numerous aromatic carboxylic acid esters (e.g., phenyl acetate), and hence combats the toxic effect of organophosphates. The aim of the present investigation is to evaluate the arylesterases of Ancylostoma duodenale giving special importance to structure generation, validation of the generated models, distribution of secondary structural elements and positive charge distribution over the structure. By the implementation of comparative modeling approach we propose the first molecular model structure of arylesterases of Ancylostoma duodenale.

Molecular identification of Ancylostoma species from dogs and an assessment of zoonotic risk in low-income households, São Paulo State, Brazil

Hookworm infection stands out for its worldwide distribution and for its veterinary and public health relevance. Based on copromicroscopic examinations and polymerase chain reaction (PCR) amplification of the ITS1-5.8S-ITS2 region, we assessed, respectively, the prevalence of intestinal parasites and the identification of canine hookworm species in faeces recovered from 278 dogs living in households of an inland municipality of São Paulo State, Brazil. Intestinal parasites were found in 67.3% of dogs and hookworm infection was found at the highest prevalence rate (56.6%), followed by Toxocara canis (11.9%), Isospora spp. (11.9%), Giardia spp. (5.8%), Sarcocystis spp. (4.0%), 'Hammondia-like' (1.4%), Dipylidium caninum (1.1%) and Trichuris vulpis (0.7%). Of 158 samples positive for hookworm eggs, 106 (67.1%) were amplified by PCR and, of those, 88 (55.7%) were successfully sequenced for species identification. Single infections with Ancylostoma caninum and Ancylostoma braziliense were recorded in 61.4% and 12.5%, respectively, and mixed infections were found in 26.1%. The nucleotide sequences of both species showed high identity rates (98-100%) when compared with reference sequences. Although A. caninum was the most prevalent hookworm in the dogs assessed, the occurrence of both A. caninum and A. braziliense in single and/or mixed infections poses a potential risk for the local population in a low-income area, especially children, to acquire cutaneous larva migrans (CLM).

Study on prevalence of ancylostomosis in dogs at Anand district, Gujarat, India

Aim:

This study was undertaken to derive the prevalence rate of ancylostomosis in dogs by a collection of fecal samples from Anand district.

Materials and Methods:

The fecal samples were collected from the dogs brought to the Hospital of Veterinary College (Teaching Veterinary Clinical Service Complex) and the surrounding areas of Anand district. On the day of collection, fecal samples were collected and brought to the Department of Veterinary Parasitology and processed for standard qualitative examination. The sedimentation technique was used to detect the presence of Ancylostoma spp. eggs in the samples.

Result:

The highest prevalence rate was observed in the month of May (36.66% fecal samples) and the lowest in the month of December (13.79% fecal samples) at Anand district.

Conclusion:

It can be concluded that heavy infection is present in Anand district especially in the season of summer followed by monsoon and the least in winter.

Detection of Helminth Eggs and Identification of Hookworm Species in Stray Cats, Dogs and Soil from Klang Valley, Malaysia

The present study was conducted to determine the prevalence of helminth eggs excreted in the faeces of stray cats, dogs and in soil samples. A total of 505 fresh samples of faeces (from 227 dogs and 152 cats) and soil were collected. The egg stage was detected via microscopy after the application of formalin–ether concentration technique. Genomic DNA was extracted from the samples containing hookworm eggs and used for further identification to the species level using real-time polymerase chain reaction coupled with high resolution melting analysis. Microscopic observation showed that the overall prevalence of helminth eggs among stray cats and dogs was 75.7% (95% CI = 71.2%–79.9%), in which 87.7% of dogs and 57.9% of cats were infected with at least one parasite genus. Five genera of heliminth eggs were detected in the faecal samples, including hookworms (46.4%), Toxocara (11.1%), Trichuris (8.4%), Spirometra (7.4%) and Ascaris (2.4%). The prevalence of helminth infections among stray dogs was significantly higher than that among stray cats (p < 0.001). Only three genera of helminths were detected in soil samples with the prevalence of 23% (95% CI = 15.1%–31%), consisting of hookworms (16.6%), Ascaris (4%) and Toxocara (2.4%). The molecular identification of hookworm species revealed that Ancylostoma ceylanicum was dominant in both faecal and soil samples. The dog hookworm, Ancylostoma caninum, was also detected among cats, which is the first such occurrence reported in Malaysia till date. This finding indicated that there was a cross-infection of A. caninum between stray cats and dogs because of their coexistent within human communities. Taken together, these data suggest the potential role of stray cats and dogs as being the main sources of environmental contamination as well as for human infections.

Stray animal and human defecation as sources of soil-transmitted helminth eggs in playgrounds of Peninsular Malaysia

Soil contaminated with helminth eggs and protozoan cysts is a potential source of infection and poses a threat to the public, especially to young children frequenting playgrounds. The present study determines the levels of infection of helminth eggs in soil samples from urban and suburban playgrounds in five states in Peninsular Malaysia and identifies one source of contamination via faecal screening from stray animals. Three hundred soil samples from 60 playgrounds in five states in Peninsular Malaysia were screened using the centrifugal flotation technique to identify and determine egg/cyst counts per gram (EPG) for each parasite. All playgrounds, especially those in Penang, were found to be contaminated with eggs from four nematode genera, with Toxocara eggs (95.7%) the highest, followed by Ascaris (93.3%), Ancylostoma (88.3%) and Trichuris (77.0%). In addition, faeces from animal shelters were found to contain both helminth eggs and protozoan cysts, with overall infection rates being 54% and 57% for feline and canine samples, respectively. The most frequently occurring parasite in feline samples was Toxocara cati (37%; EPG, 42.47 ± 156.08), while in dog faeces it was Ancylostoma sp. (54%; EPG, 197.16 ± 383.28). Infection levels also tended to be influenced by season, type of park/playground and the texture of soil/faeces. The occurrence of Toxocara, Ancylostoma and Trichuris eggs in soil samples highlights the risk of transmission to the human population, especially children, while the presence of Ascaris eggs suggests a human source of contamination and raises the issue of hygiene standards and public health risks at sites under investigation.

Probiotic therapy: a promising strategy for the control of canine hookworm

Canis familiaris is a domestic animal which plays an important role as a pet; however, it is very likely to develop diseases characterized by high morbidity and mortality. In this sense, there are some Ancylostomatidae species that can lead to anemia, weight loss, and abdominal pain. Therefore, the treatment with allopathic drugs is essential for eliminating the parasitism. However, the increasing occurrence of resistance to allopathic treatments stimulates the search for new therapeutic inputs, among which the probiotics stand out and are able to positively alter the intestinal microbiota and exert immunomodulatory effect. Therefore, the present study aimed to evaluate the applicability of using species of Lactobacillus (L. acidophilus ATCC 4536, L. plantarum ATCC 8014, and L. delbrueckii UFV H2B20) to control canine ancylostomiasis. A probiotic preparation containing 1 × 10⁶ CFU of each strain was administered to 10 naturally infected animals, on alternate days for 28 days. It was observed that the treatment with the probiotic preparation led to a significant reduction in EPG of feces (88.83%/ P < 0.05), as well as an increase in leukocyte and lymphocyte counts, highlighting the potential use of Lactobacillus species in the control of canine ancylostomiasis.

Molecular detection of Ancylostoma duodenale, Ancylostoma ceylanicum, and Necator americanus in humans in northeastern and southern Thailand

The 2 principal species of hookworms infecting humans are Necator americanus and Ancylostoma duodenale. Case studies on zoonotic hookworm infections with Ancylostoma ceylanicum and/or Ancylostoma caninum are known mainly from Asian countries. Of these 2 zoonotic species, only A. ceylanicum can develop to adulthood in humans. In the present study, we report a molecular-based survey of human hookworm infections present in southern and northeastern Thailand. Thirty larval hookworm samples were obtained from fecal agar plate cultures of 10 patients in northeastren Thailand and 20 in southern Thailand. Partial ITS1, 5.8S, and ITS2 regions of the ribosomal DNA genes were amplified using PCR. The amplicons were sequenced, aligned, and compared with other hookworm sequences in GenBank database. The results showed that, in Thailand, N. americanus is more prevalent than Ancylostoma spp. and is found in both study areas. Sporadic cases of A. ceylanicum and A. duodenale infection were seen in northeastern Thailand.

Molecular identification of hookworms in stray and shelter dogs from Guangzhou city, China using ITS sequences

Canine hookworm infections are endemic worldwide, with zoonotic transmission representing a potentially significant public health concern. This study aimed to investigate hookworm infection and identify the prevalent species from stray and shelter dogs in Guangzhou city, southern China by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) based on internal transcribed spacer (ITS) sequences. From March 2011 to July 2012, fresh faecal samples from a total of 254 dogs were obtained from five locations, namely Conghua, Baiyun, Liwan, Haizhu and Panyu, in Guangzhou. These samples were screened for the presence of hookworm eggs using light microscopy, with an overall prevalence of 29.53% being recorded. The highest prevalence of 45.28% was found in suburban dogs from Conghua compared with lower values recorded in urban dogs in Haizhu (21.43%), Baiyun (18.97%), Panyu (18.18%) and Liwan (15%). The prevalence in stray dogs was significantly higher than that in shelter dogs. PCR-RFLP analysis showed that 57.33% were detected as single hookworm infections with Ancyclostoma caninum, and 22.67% as A. ceylanicum, while 20% were mixed infections. This suggests that high prevalences of both hookworm species in stray and shelter dogs in China pose a potential risk of transmission from pet dogs to humans.

Genetic characterization of the partial mitochondrial cytochrome oxidase c subunit I (cox 1) gene of the zoonotic parasitic nematode, Ancylostoma ceylanicum from humans, dogs and cats

Ancylostoma ceylanicum is the only zoonotic hookworm species that is able to produce patent infections in humans with the majority of cases reported in South East Asia. Over the past few years, there have been an increasing number of studies investigating the prevalence of this parasitic zoonosis using molecular diagnostic tools and a single genetic locus as marker for species identification. As there can be limitations in using a single genetic locus for epidemiological studies and genetic discrimination, the complementary use of a more variable locus will provide additional evidence to support the zoonotic exchange of hookworm species between humans and animals. In the present study, the cytochrome c oxidase subunit 1 (cox 1) sequence of A. ceylanicum from positive human and animal fecal samples were determined and compared with published reference sequences. Phylogenetic analysis demonstrated that isolates of A. ceylanicum were divided into two clusters, one consisting 3 human isolates and the other comprising 19 isolates of human and animal origin from different geographical locations within Malaysia. The two groups of A. ceylanicum could be distinguished from one another through five fixed nucleotide differences at locations 891, 966, 1008, 1077 and 1083. The detection of genetically distinct groups and considerable level of genetic variation within the cox 1 sequence of A. ceylanicum might suggest potential haplotype-linked differences in zoonotic, epidemiological and pathobiological characteristics, a hypothesis that still needs further investigation.

First report of Ancylostoma ceylanicum in wild canids

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First report of Ancylostoma ceylanicum in wild canids.

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Ancylostoma ceylanicum, A. caninum and A. braziliense are prevalent in wild dogs in the Wet Tropics of Australia.

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A zoonotic risk exists from the reservoir of hookworms in wild dogs to communities in the Wet Tropics.

The parasitic nematode Ancylostoma ceylanicum is common in dogs, cats and humans throughout Asia, inhabiting the small intestine and possibly leading to iron-deficient anaemia in those infected. It has previously been discovered in domestic dogs in Australia and this is the first report of A. ceylanicum in wild canids. Wild dogs (dingoes and dingo hybrids) killed in council control operations (n = 26) and wild dog scats (n = 89) were collected from the Wet Tropics region around Cairns, Far North Queensland. All of the carcasses (100%) were infected with Ancylostoma caninum and three (11.5%) had dual infections with A. ceylanicum. Scats, positively sequenced for hookworm, contained A. ceylanicum, A. caninum and Ancylostoma braziliense, with A. ceylanicum the dominant species in Mount Windsor National Park, with a prevalence of 100%, but decreasing to 68% and 30.8% in scats collected from northern and southern rural suburbs of Cairns, respectively. Due to the ability of A. ceylanicum to cause a patent infection in humans, the zoonotic risk arising from this wild dog reservoir to communities in the Wet Tropics should be determined.