Unveiling zoonotic threats: molecular identification of Brugia sp. infection in a lion.

Brugia malayi and B. pahangi, potential zoonotic pathogens transmitted by mosquitoes, are believed to primarily infect dogs and cats as reservoir hosts. Although previous studies have indicated nematode infections in lions, particularly in zoo environments where human contact with these reservoirs is possible, limited documentation exists regarding Brugia sp. infections in lions in Thailand. This study aims to investigate a case of Brugia infection in a lion from a zoo in Thailand. The blood sample was collected and examined from a female lion, using staining methods to morphologically identify microfilaria at the genus level. Subsequently, the PCR was employed targeting specific genes, including mitochondrial 12S rDNA, 18S rDNA, cytochrome oxidase I (COI) and Wolbachia surface protein (wsp), to confirm the species of the filarial nematode parasite. The genetic sequencing results revealed a high similarity (99-100%) to B. malayi for the 12S rDNA, 18S rDNA, COI and wsp genes. Phylogenetic analysis based on nucleotide sequences from the 12S rDNA, 18S rDNA, COI and wsp genes showed that the sequences from this study belong to different clusters. This marks the inaugural documentation of molecular identification of Brugia infection in a lion, signifying that lions could function as reservoirs for this parasite and present a potential public health risk in the region. Our research underscores the effectiveness of molecular techniques and phylogenetic analysis in discerning and comprehending the evolution of filarial parasites. Additionally, it emphasizes the significance of these methods in enhancing the diagnosis, control, and prevention of zoonotic filarial nematode infections.

Metabarcoding study to reveal the structural community of strongylid nematodes in domesticated horses in Thailand.

BACKGROUND: Mixed strongylid infections significantly impact equine health and performance. Traditional microscopy-based methods exhibit limitations in accurately identifying strongylid species. Nemabiome deep amplicon sequencing approach previously succeeded in describing the strongylid communities in livestock including equids. However, there are no available studies that describe the structural communities of strongylid parasites in horses in Thailand. Therefore, this study was undertaken encompassing the ITS-2 rDNA metabarcoding assay to characterize strongylid species within horse fecal samples collected from a cohort of yearlings at the largest domesticated stud farm in Thailand. In addition, to investigate the capability of ITS-2 rDNA in assessing the phylogenetic relationships among the identified strongylid species. RESULTS: The study identified 14 strongylid species in the examined equine populations, each with varying prevalence. Notably, Cylicocyclus nassatus and Cylicostephanus longibursatus were identified as the predominant species, with Strongylus spp. conspicuously absent. The phylogenetic analysis of 207 amplicon sequence variants (ASVs) displayed a complex relationship among the investigated cyathostomin species, with some species are positioned across multiple clades, demonstrating close associations with various species and genera. CONCLUSION: The ITS-2 nemabiome sequencing technique provided a detailed picture of horse strongylid parasite species in the studied population. This establishes a foundation for future investigations into the resistance status of these parasites and enables efforts to mitigate their impact.

Patterns of Equine Small Strongyle Species Infection after Ivermectin Intervention in Thailand: Egg Reappearance Period and Nemabiome Metabarcoding Approach.

The indiscriminate use of anthelmintics to control parasitic nematodes in horses has led to the emergence of anthelmintic resistance worldwide. However, there are no data available on using ivermectin for treating strongyle infections within domesticated horses in Thailand. Therefore, this study aimed to use the fecal egg count reduction (FECR) test to determine the strongylid egg reappearance period (ERP). Additionally, the nemabiome metabarcoding approach is incorporated to study patterns of strongyle species infection following ivermectin treatment. The study results indicate that, although ivermectin effectively eliminated adult strongyle parasites within two weeks post-treatment, the ERP was shortened to 6 weeks post-treatment with a mean FECR of 70.4% (95% CI 46.1-84.0). This potentially indicates a recent change in drug performance. In addition, nemabiome metabarcoding revealed that strongyle species have different levels of susceptibility in response to anthelmintic drugs. The reduction in ERP was associated with the early reappearance of specific species, dominated by Cylicostephanus longibursatus and Cylicocyclus nassatus, indicating the lower susceptibility of these species. In contrast, Poteriostomum imparidentatum, Triodontophorus nipponicus, and Triodontophorus serratus were not found post-treatment, indicating the high level of susceptibility of these species. This information is vital for comprehending the factors contributing to the emergence of resistance and for devising strategies to manage and control strongyle infections in horses.

First molecular detection and genetic diversity of Hepatozoon sp. (Apicomplexa) and Brugia sp. (Nematoda) in a crocodile monitor in Nakhon Pathom, Thailand.

The crocodile monitor (Varanus salvator) is the most common monitor lizard in Thailand. Based on habitat and food, they have the potential to transmit zoonoses, with a high possibility of infecting ectoparasites and endoparasites. Diseases that could infect crocodile monitors and be transmitted to other animals, including humans. This research aims to identify and evaluate the phylogenetic relationships of Hepatozoon sp. and sheathed microfilaria in crocodile monitors. The phylogenetic analyses of Hepatozoon, based on 18S rRNA, and sheathed microfilaria, based on the COX1 gene, revealed that the Hepatozoon sp. were grouped with H. caimani, while sheathed microfilaria were grouped together with B. timori. This study provides insights into the genetic diversity and host-parasite interactions of hemoparasites in crocodile monitors in Thailand.

New insight into genetic diversity of zoonotic-potential Ancylostoma ceylanicum in stray cats living in Bangkok, Thailand, based on deep amplicon sequencing.

AIMS: This study aimed to characterize feline hookworms from stray cats living in Bangkok. METHODS AND RESULTS: A total of 56 hookworm-positive faecal samples were identified for hookworm species by using PCR targeting the ITS1, 5.8S, and ITS2 fragment and qPCR targeting ITS2. Of 56 samples, 96.4% (54/56) were identified as Ancylostoma ceylanicum and 1.8% (1/56) as Ancylostoma caninum. With qPCR, 89.3% (50/56) were identified as single A. ceylanicum infection and 5.4% (3/56) as coinfection of A. ceylanicum and A. caninum. For genetic characterization of A. ceylanicum, 10 samples were pooled, and the partial COI gene was amplified, followed by deep amplicon sequencing. Five pooled samples were analysed, and 99.73% were identified with A. ceylanicum sequences, which were allocated into 19 haplotypes (AC01-AC19). Genetic diversity findings for A. ceylanicum in Asia revealed that three of eight haplotypes considered of zoonotic significance occurred in humans, dogs, and cats, including haplotypes H01, H20, and H21. The predominant haplotype in this study, AC01, was clustered with H01-a zoonotic haplotype. CONCLUSIONS: The diversity obtained by deep amplicon sequencing supported that the A. ceylanicum community had high genetic variation. Deep amplicon sequencing was a useful method to determine source, zoonotic potential, and host-parasite relationship.

Genetic diversity and characterization of Wolbachia endosymbiont in canine filariasis.

Canine filariasis is caused by nematodes from the family Onchocercidae, which is transmitted by arthropod vectors. The disease is commonly found in Southeast Asia and exists worldwide. Some filarial nematodes are associated with intracellular bacteria of the genus Wolbachia, which plays an important role in embryogenesis, molting, and the long-term survival of adult worms. This study aims to characterize Wolbachia sp. and determine the association between Wolbachia and canine filarial nematode species in Thailand. A total of 46 dog blood samples that were naturally infected with filarial nematodes were obtained to identify filarial nematode species by Giemsa stained under a light microscope and confirmed using the molecular technique. In order to characterize Wolbachia sp., the nested PCR assay targeting the 16S rRNA gene showed that all samples of Dirofilaria immitis and fifteen samples of Candidatus Dirofilaria hongkongensis were grouped into Wolbachia supergroup C. In addition, all samples of Brugia spp. and five samples of Candidatus Dirofilaria hongkongensis were classified into Wolbachia supergroup D. The genetic diversity analysis conducted using the 16S rRNA gene revealed a similar result when analyzed through phylogenetic tree analysis. This is the first genetic diversity study of Wolbachia of Candidatus Dirofilaria hongkongensis in infected dogs in Thailand.

Pathological effects due to metacercariae of Clinostomum piscidium migration in snakeskin gourami (Trichopodus pectoralis) in Thailand.

Clinostomum spp. is a fish-borne pathogen and a digenetic trematode with a global range. Despite its zoonotic relevance, the pathogenic impact of the parasite in Thai aquaculture is currently unclear. The present study deals with the pathogenic changes that fluke causes in their host, Trichopodus pectoralis, and the molecular confirmation of the Clinostomum piscidium by targeting 18 s rDNA and ITS gene. The metacercariae of C. piscidium were discovered in the body cavity of infected fish. The gross pathological examination revealed a few white migratory tracks on the surface of the liver and spleen. The migratory track showed histologically as a primary hemorrhage and necrosis of hepatic cells surrounded by a layer of macrophages and epithelioid cells, inflammatory cells, and eosinophilic granular cells in the cytoplasm of liver cells and close to the epithelial cells of the intestine. Also, the migratory track in the spleen appeared as a marked decrease of Red Blood Cell (RBC) count and changes in the necrotic tissue. Infection with this metacercaria produced hepatic tissue injury, which disrupted hepatic metabolism and decreased body weight in the fish hosts. The findings of the study suggest that the pathological effect of C. piscidium on farm T. pectoralis can cause significant economic loss by stunting fish development and predisposing fish to opportunistic pathogens in the environment. Hence, the treatment and control of C. piscidium infections are crucial for the viability of the aquaculture sector since this parasite has been found to cause pathological damage to the vital organs of fish.

Molecular identification and genetic diversity of equine ocular setariasis in Thailand based on the COI, 12S rDNA, and ITS1 regions.

Equine ocular setariasis is mainly caused by Setaria digitata, and the identification of this filarial nematode is based on morphology. However, morphological characterization alone is insufficient for the detection and differentiation of S. digitata from its congeners. In Thailand, the molecular detection of S. digitata is lacking and its genetic diversity is still unknown. This study aimed to phylogenetically characterize equine S. digitata from Thailand based on sequences derived from the mitochondrial cytochrome c oxidase subunit 1 (COI), the mitochondrial small subunit ribosomal DNA (12S rDNA), the nuclear internal transcribed spacer 1 (ITS1) and Wolbachia surface protein (wsp). Five samples of S. digitata were characterized, submitted to the NCBI database, and used for phylogenetic analysis as well as the assessment of similarity, entropy, and haplotype diversity. Phylogenetic analyses revealed that the S. digitata Thai strain was similar to S. digitata from China and Sri Lanka, with 99 to 100% similarity. The entropy and haplotype diversity indicated that the S. digitata Thai isolate was conserved and closely related to S. digitata worldwide. This is the first report on the molecular detection of equine ocular setariasis caused by S. digitata in Thailand.

First report of Strongylidae nematode from pilot whale (Globicephala macrorhynchus) by molecular analysis reveals the cosmopolitan distribution of the taxon.

This study investigates the identification, genetic composition, and placement in the evolutionary tree of a particular nematode species found in a short-finned pilot whale in the Gulf of Thailand. To accomplish this, we utilized various methods, including microscopic observations, molecular techniques, and comparative analyses to better understand the characteristics of this parasite. Initially, we concentrated on studying the 18s rDNA sequence through nested PCR, resulting in a 774-bp product. After conducting a BLASTn analysis, we discovered that there were only a few sequences in the GeneBank that shared similarities with our nematode, particularly with Cyathostomum catinatum, although the percent identity was relatively low. To confirm the uniqueness of our sequence, we constructed a phylogenetic tree that demonstrated a distinct branch for our nematode, suggesting significant genetic differentiation from C. catinatum. Additionally, we sequenced a 399-bp section of the ITS2 gene using PCR, and the resulting data showed a close association with the Strongylidae family, specifically with Cylicocyclus insigne. This was further confirmed by BLASTn and CD-HIT-est results, which indicated a 99 and ~94% sequence homology with C. insigne, respectively. The ITS2 phylogenetic tree also supported the position of our isolated sequence within the Strongylidae family, clustering closely with C.insigne. Our findings shed light on the genetic connections, taxonomy, and evolutionary trends within the Strongylidae family, with a particular focus on the widespread nature of the Cylicocyclus genus. This study emphasizes the importance of utilizing molecular techniques and interdisciplinary approaches to gain insight into nematode diversity, evolution, and ecological dynamics in marine environments.

Human social conditions predict the risk of exposure to zoonotic parasites in companion animals in East and Southeast Asia.

BACKGROUND: A recent dramatic surge in pet ownership has been observed across metropolitan areas in Asia. To date, there is a dearth of information on the risk associated with pet ownership for the transmission of parasites on a large scale in Asia, despite this continent giving rise to the largest burden of zoonotic infections worldwide. METHODS: We explored the nature and extent of zoonotic internal (endo-) and external (ecto-) parasites and arthropod-borne pathogens in 2381 client-owned dogs and cats living in metropolitan areas of eight countries in East and Southeast Asia using reliable diagnostic tests and then undertook extensive statistical analyses to define predictors of exposure to zoonotic pathogens. RESULTS: The estimated ORs for overall parasite infections are 1.35 [95% CIs 1.07;1.71] in young animals and 4.10 [1.50;11.2] in the animal group older than 15 years as compared with adult animals, 0.61 [0.48;0.77] in neutered animals as compared to unneutered animals, 0.36 [0.26;0.50] in animals living in urban areas as compared with rural areas, 1.14 [1.08;1.21] for each 1 °C increase of annual mean temperature which varies from 12.0 to 28.0 °C, and 0.86 [0.78;0.95] for each year of life expectancy which varies from 70.9 to 83.3 years. CONCLUSIONS: Here we highlight the influence of human life expectancy and the neutering status of the animals, which reflect increased living standards through access to education and human and veterinary health care, to be both strongly associated with exposure to zoonotic parasites. An integrated approach of local and international authorities to implement and manage educational programs will be crucial for the control of zoonotic infections of companion animals in Asia.

Parasites live on or inside animals or humans and can cause disease. Companion animals (pets) with parasites present a potential risk to the health of their owners, as certain kinds of parasites (known as zoonotic parasites) can affect both animal and human health. Here, we investigated whether human social conditions are associated with zoonotic parasite infections in companion animals in East and Southeast Asia. We found that higher human life expectancy and neutering of the companion animals were associated with fewer zoonotic parasite infections in the animals. These findings highlight the need for an enhanced commitment of local authorities to establish prevention campaigns, including education programs, against zoonotic pathogens. These measures will play a crucial role in alleviating the impact of these diseases in companion animals and humans in Asia.

World Association for the Advancement of Veterinary Parasitology (WAAVP): Second edition of guidelines for evaluating the efficacy of anthelmintics for dogs and cats.

These revised guidelines have been developed to assist in the design, execution, and interpretation of studies to assess the efficacy of anthelmintic drugs against internal parasites in dogs and cats. The design and execution of studies are outlined and discussed. Considerations for specific targeted parasites are included. Information is provided on the principles of selection of animals, procedures for randomization, housing, feeding, necropsy procedures, and record keeping for dose determination dose confirmation studies and field studies. Complementary to the WAAVP general anthelmintic guidelines, these species-specific guidelines should assist investigators in the evaluation of anthelmintic drugs in dogs and cats by using comparable and standardized procedures in studies with appropriate numbers of animals.

Case report: Thromboembolic heartworm induced lower limb necrosis in a dog.

A 9-year-old spayed female boxer suffered from lameness in both hindlimbs with a perforated paw wound. Additionally, a linear, worm-like creature was penetrating out from the wound. On examination, the dog was emaciated and infected with heartworms, detected through a fresh blood smear, echocardiography, and transabdominal ultrasonography. Adult heartworms were detected at the right atrium (RA), right ventricle (RV), and pulmonary artery (PA), including the distal abdominal aorta, external iliac, and femoral arteries. During the surgery, adults heartworms were removed from both the heart (n = 8) and the femoral arteries (n = 5). Unfortunately, not all heartworms could be removed from these locations due to the extent of the heartworm infection. The opened, ischemic wounds in the distal limbs progressively expanded and the dog subsequently died, possibly due to caval syndrome complications and septicemia. The necropsy showed no evidence of an atrial septal defect, and a total of 25 adult heartworms were collected from the perforated paw, heart, pulmonary, and femoral arteries. All worms collected during the necropsy process were molecularly confirmed to be Dirofilaria immitis.

Application of a novel rectangular filtering microfluidic device for microfilarial detection.

The rectangular filtering microfluidic chip was invented using microfluidics device fabrication technology and can separate living microfilariae from blood samples without a syringe pump. The diagnostic results are highly effective. The device is based on the principle of separating millions of blood cells from microfilariae using a rectangular filter structure. It disperses fluid evenly into the flow-passage channel, and its rectangular filter structure is the key to success in reducing the pressure and separating blood cells from microfilariae effectively. The flow rate and blood cell concentration were optimized in our study. The chip is intended to be a point-of-care device that can reduce the use of superfluous instrumentation in the field. The technology is designed to be rapid, accurate, and easy-to-use for all users, especially those in remote areas.

Case Report: Molecular and Pathological Investigations of Zoonotic Anatrichosoma Spp.-Induced Ulcerative Pododermatitis in a Domestic Cat in Thailand.

Anatrichosoma spp. is a group of trichuroid nematodes that mainly infect non-human primates and domestic cats. The lifecycle of these nematodes remains unclear. In non-human primates, Anatrichosoma spp. were found in the nasal cavity. However, ulcerative dermatitis has been reported in infected cats. An adult, intact, female domestic short-haired cat was presented with ulcerative pododermatitis of all limbs. Punch biopsy was performed at the edge of the ulcerative wound for histopathological investigation and showed necrosis and infiltration of inflammatory cells around the nematode-like lesion. Eggs with Capillaria-like characteristics were present. Tissue sections were subjected to DNA extraction and PCR targeting 18S rRNA, using primers designed from Anatrichosoma 18S rRNA. The phylogenetic tree revealed that DNA obtained from the lesion of the domestic cat was grouped with Anatrichosoma spp. from the olive glass mouse (Abothirx olivacea), Capillaria plica and Eucoleus aerophilus, both from the red fox (Vulpes Vulpes). The study is the first report of feline anatrichosomiasis in Thailand, and we present both pathological findings and molecular evidence. The cat was successfully treated with emodepsine/praziquantel. The skin lesion recovered within 3 days after anthelmintic treatment. Because Anatrichosoma spp. have been reported in humans, the zoonotic potential of this parasite should be considered.

Characterization of serum protein electrophoresis patterns and C-reactive protein in canine tick-borne diseases.

BACKGROUND AND AIM: Canine tick-borne diseases are important diseases with a worldwide distribution. In Thailand, the most important canine tick-borne diseases are ehrlichiosis, babesiosis, and hepatozoonosis. This study aimed to determine the serum protein electrophoresis patterns (SPEPs) and C-reactive protein (CRP) levels associated with Ehrlichia canis , Babesia canis, or Hepatozoon canis single infections. MATERIALS AND METHODS: A total of 650 canine blood samples were collected from animal hospitals and clinics in Bangkok and its vicinity to examine health status and blood parasite infection. Suspected blood parasite infections were examined by buffy coat thin blood smear and confirmed by polymerase chain reaction. Normal dog and positive E. canis , B. canis, and H. canis single infections and serum protein profiles were determined by agarose gel electrophoresis. CRP concentration was measured by fluorescent immunoassay. RESULTS: In dogs infected with E. canis, B. canis, and H. canis single infections, albumin levels and A/G ratios significantly decreased, whereas ß2-globulin levels increased (p<0.05). The γ-globulin level significantly increased in E. canis and H. canis infections (p<0.05). A monoclonal gammopathy pattern wasi observed in E. canis and B. canis sngle infections, whereas ß-γ bridging patterns and increased ß- and γ-globulin fractions were found in H. canis single infections. The CRP level increased in dogs with blood parasite single infections and may be related to the pathogenesis of the infection. CONCLUSION: SPEPs and CRP levels can be used to monitor health status and blood parasite problems in infected dogs.

Serum protein profiles and C-reactive protein in natural canine filariasis.

BACKGROUND AND AIM: Canine filariasis is caused by several species of filarial worms. The pathophysiological response to infection is mainly due to the filaria lifecycle. Laboratory detection methods to assess the pathological alterations characteristic of filariasis are needed urgently. Serum protein profiles and C-reactive protein (CRP) levels are used widely to diagnose several animal diseases. This study aimed to determine the serum protein profiles and CRP levels in dogs infected with Dirofilaria immitis or Brugia pahangi or both parasites. MATERIALS AND METHODS: Blood samples were collected from 980 dogs presenting at animal hospitals and veterinary clinics in Bangkok and its vicinity. The presence of microfilaria in samples was determined using a buffy coat smear and staining with Wright-Giemsa. The sheathed and unsheathed microfilaria species were identified by acid phosphatase staining. Forty positive samples were tested. The serum protein profiles were identified by agarose gel electrophoresis. The CRP concentration was measured using a fluorescent immunoassay. RESULTS: Albumin levels and albumin-to-globulin ratios were significantly lower, and total protein, ß2 globulin, and γ globulin levels were significantly elevated in dogs infected with D. immitis and B. pahangi compared with reference values in normal dogs. The average CRP concentrations in dogs infected with D. immitis or B. pahangi were 69.9 and 12.9 mg/L, respectively. CONCLUSION: The total protein and γ globulin levels increased in canine filariasis compared with the normal reference range. The CRP concentration in dogs infected with D. immitis was extremely high, whereas that in dog infected with B. pahangi was normal.

Seasonal distribution and environmental parameters associated with Brugia pahangi and Dirofilaria immitis in naturally infected dogs in Bangkok and vicinity, Thailand.

Dirofilaria immitis and Brugia pahangi are vector-borne parasites found in dogs and cats, including Thailand. In order to evaluate the effects of season and environmental parameters on the prevalence of these parasites, this retrospective study was conducted in 2019. A total of 79,506 canine blood samples were examined. B. pahangi was found in 0.55% of samples (438/79,506; 95% CI 0.50-0.61) while D. immitis was detected in 0.43% (345/79,506; 95% CI 0.39-0.48). One-way ANOVA found no effect of seasonal conditions on prevalence. For B. pahangi, the parameters rainfall, relative humidity and sunshine hours showed associations with p ≤ 0.20 and were included in multiple logistic regressions resulting in adjusted odds ratios of 0.53, 1.31 and 0.55, respectively. For D. immitis, only average temperature showed p ≤ 0.20, resulting in an odds ratio of 0.42. In conclusion, Thailand has environmental parameters that do not change very much during the year, so they might not affect the prevalence of two filarial nematodes. However, the threat of B. pahangi and D. immitis should not be ignored, especially in subtropical regions where their vectors are abundant. Both owners and veterinarians should be concerned about filarial prevention and control of D. immitis and B. pahangi.

Emergence of Dirofilaria repens (Spirurida: Onchocercidae) in dogs in Eastern Thailand.

BACKGROUND AND AIM: Dirofilaria repens is a zoonotic vector-borne parasite of dogs and cats. It is not commonly found in every part of Thailand, except the southern part. This study was conducted to investigate the prevalence of this parasite in Eastern Thailand in 2019. MATERIALS AND METHODS: A total of 8003 blood samples were collected from private veterinary clinics and animal hospitals in Eastern Thailand. Blood parasites were examined using buffy coat thin blood smears with Wright-Giemsa staining. D. repens was morphologically identified and confirmed using the acid phosphatase activity technique. RESULTS: The first case of D. repens was found in March 2019. The prevalence of D. repens from January to December 2019 was 0.44% (35/8003) (95% confidence interval 0.30-0.61). CONCLUSION: The prevalence data of D. repens in Eastern Thailand indicate that this parasitic infection should be considered as a zoonotic vector-borne disease. A strategic plan to control zoonotic transmission alongside a preventive program should be emphasized and encouraged among pet owners and veterinarians.

Efficacy of Broadline® in cats against induced infections with developing fourth-stage larval and adult Ancylostoma ceylanicum hookworms.

Ancylostoma ceylanicum hookworms parasitize dogs and cats in subtropical and tropical South East Asia and Pacific region, the Arab Peninsula, southern Africa and South America but cause patent infections in humans too. To evaluate the efficacy of Broadline®, a combination product comprising eprinomectin, fipronil, (S)-methoprene and praziquantel, against developing fourth-larval stage (L4) and adult A. ceylanicum in cats, a blinded, induced infection study was conducted. Following oral inoculation of 24 purpose bred cats with ˜300 infectious A. ceylanicum larvae each, cats were allocated to one of three groups of eight animals, each which served either as untreated controls or received Broadline® (once topically at the minimum label dose of 0.12 mL per kg bodyweight) when the hookworms were L4 (five days post inoculation, dpi) or adults (25 dpi). Efficacy was determined on nematode counts following necropsy of the cats. Fecal examination at 22 dpi confirmed that all cats of the control group and of the group to be treated when the hookworms were adult were excreting hookworm eggs (range, 100 to 1000 eggs per gram) while no eggs were recovered from the feces of the cats treated with Broadline® 5 dpi. Nematode counts established 35 dpi demonstrated that Broadline® treatment was 100% efficacious against both, developing L4 and adult A. ceylanicum: no hookworms were recovered from any Broadline®-treated cat while all control animals harbored A. ceylanicum (range, 8-35) (p < 0.001). No health problems were observed throughout the study.

Molecular detection of pathogens in ticks and fleas collected from companion dogs and cats in East and Southeast Asia.

BACKGROUND: Ticks and fleas are considered amongst the most important arthropod vectors of medical and veterinary concern due to their ability to transmit pathogens to a range of animal species including dogs, cats and humans. By sharing a common environment with humans, companion animal-associated parasitic arthropods may potentially transmit zoonotic vector-borne pathogens (VBPs). This study aimed to molecularly detect pathogens from ticks and fleas from companion dogs and cats in East and Southeast Asia. METHODS: A total of 392 ticks and 248 fleas were collected from 401 infested animals (i.e. 271 dogs and 130 cats) from China, Taiwan, Indonesia, Malaysia, Singapore, Thailand, the Philippines and Vietnam, and molecularly screened for the presence of pathogens. Ticks were tested for Rickettsia spp., Anaplasma spp., Ehrlichia spp., Babesia spp. and Hepatozoon spp. while fleas were screened for the presence of Rickettsia spp. and Bartonella spp. RESULT: Of the 392 ticks tested, 37 (9.4%) scored positive for at least one pathogen with Hepatozoon canis being the most prevalent (5.4%), followed by Ehrlichia canis (1.8%), Babesia vogeli (1%), Anaplasma platys (0.8%) and Rickettsia spp. (1%) [including Rickettsia sp. (0.5%), Rickettsia asembonensis (0.3%) and Rickettsia felis (0.3%)]. Out of 248 fleas tested, 106 (42.7%) were harboring at least one pathogen with R. felis being the most common (19.4%), followed by Bartonella spp. (16.5%), Rickettsia asembonensis (10.9%) and "Candidatus Rickettsia senegalensis" (0.4%). Furthermore, 35 Rhipicephalus sanguineus ticks were subjected to phylogenetic analysis, of which 34 ticks belonged to the tropical and only one belonged to the temperate lineage (Rh. sanguineus (sensu stricto)). CONCLUSION: Our data reveals the circulation of different VBPs in ticks and fleas of dogs and cats from Asia, including zoonotic agents, which may represent a potential risk to animal and human health.