Spirocerca Lupi Research Articles

Zoonotic gastrointestinal parasites of shelter dogs in Israel.

Zoonotic gastrointestinal parasites of shelter dogs in Israel.

Thoracic radiographic findings of canine spirocercosis in Australia.

Canine spirocercosis in Australia has been poorly described in the veterinary literature. The objectives of this multicentre retrospective case series were to increase the awareness of veterinarians (including teleradiology providers) regarding Spirocerca lupi in Australia and to describe the thoracic radiographic findings of dogs infected with S. lupi with comparison to other endemic regions. Fifty-nine dogs with a diagnosis of canine spirocercosis were recruited from veterinary practices located in subtropical and tropical Australia. Many (54/59; 92%) originated from Mount Isa, Queensland, due to proactive screening. Thoracic radiographs identified 42 oesophageal masses in 35/59 (59%) of affected dogs. Identification of oesophageal masses was nearly always facilitated by oesophageal gaseous distension after gastro-oesophageal endoscopy, sedation or anaesthesia (33/35, 94%). Oesophageal masses were most frequently centred at T8. Where the aorta was visualised, aortic enlargement was detected in 17/42 (40%) dogs. Spondylitis was frequently detected (32/59; 54%) and most frequently located at T8-11. Spondylosis deformans was less frequently detected (14/59; 24%) but in 7/14 (50%) studies it was present concurrently with spondylitis. Spondylitis had varied morphological features, some of which were contrary to previously reported definitions. Despite this, the radiographic appearance of spondylitis allowed relatively reliable differentiation from spondylosis deformans and added significant confidence to the radiographic diagnosis of spirocercosis. Pleural effusion (5/59; 8%) was the most frequent additional radiographic finding. In conclusion, thoracic radiographic findings of canine spirocercosis in Australia are similar to other endemic regions and S. lupi is present in multiple regions of Australia not previously reported.

Immunohistochemical Expression of GDNF, P53 and Ki67 with Tunel Assay in Canine Non-Neoplastic Esophageal Nodules Induced by Spirocerca lupi

Abstract Spirocercosis caused by Spirocerca lupi has a global distribution and mainly infects dogs although other carnivores may be affected as well. The research aimed to ascertain the proportion of cellular proliferation/apoptosis within the parasite-induced nodules and to categorize the inflammatory cells by CD3 (for T lymphocytes), CD20 (for B lymphocytes), and CD68 (for macrophages) markers. The study included 152 Iranian mixed-breed dogs (87 males and 65 females) examined for esophageal spirocercosis. The dogs underwent hematological investigations and Telemann concentration stool exams to detect the parasites’ eggs. The normal and nodular esophagi underwent TUNEL assay, histopathology, and immunohistochemical staining for GDNF, p53, Ki67, CD3, CD20, and CD68. According to our findings, 31 out of 152 dogs (20.39%) were diagnosed with spirocercosis based on clinical examinations and stool exams, while 20 out of 152 dogs (13.16%) had nodular esophagi in necropsy. Normal and nodular esophageal tissue samples (n=64) were collected from necropsied dogs. Histopathology confirmed non-neoplastic parasitic nodular lesions. Immunohistochemically, increased GDNF, Ki67, CD3, CD20, and CD68 expression was significant (p<0.05) in nodular tissue compared to normal tissue. However, the expression of p53 was not significant (p>0.05). Given the results of Ki67 expression and TUNEL assay, the rate of proliferation (6-8 times)/apoptosis (2-3 times) significantly increased (p<0.05) in the infected tissue compared to normal tissue. The results indicated that the GDNF as a neurotrophic growth factor may play an important role in the pathogenesis of nodular spirocercosis in dogs. Meanwhile, a high proliferation/apoptosis rate in the parasitic nodular compared to normal esophagi may stimulate inducing neoplastic transformation in normal esophageal tissue.

Aberrant migration of Spirocerca lupi to the spinal cord in dogs: Association of clinical signs, CSF analysis, preventive treatment, and outcome.

Spirocerca lupi is a nematode typically targeting the esophageal wall but may also migrate to the spinal cord. This study aimed to characterize the clinical presentation, cerebrospinal fluid (CSF) findings, prognostic factors, and outcomes of dogs with spinal S. lupi (SSL) aberrant migration, and to evaluate prophylactic treatment efficacy. Medical records from 2016 to 2022 were reviewed, including 284 study and 280 control dogs. Complete recovery occurred in 130/284 dogs (46 %) at 1 month, and in 214/284 dogs (75 %) at 3 months and was associated with the clinical grade at presentation (P < 0.001). Of the 162 non-ambulatory dogs, 59 % became ambulatory at 1 month, and 79 % at 3 months. Dogs with urinary incontinence were less likely to fully recover (P = 0.04). Protein CSF concentration was lower at presentation in dogs who completely recovered at 1 month and 3 months (344 mg/dL [15-1297] vs. 732 mg/dL [34-1291], P = 0.006, and 366 mg/dL [15-1297] vs. 769 mg/dL [83-1262], P = 0.025, respectively). A higher proportion of control dogs received prophylactic treatment compared to the SSL group (216/280 [77 %] vs. 168/284 [59 %], respectively, P < 0.001, OR 0.43, CI 0.30-0.62) however, prophylactic treatment did not significantly impact recovery rates. Our findings suggest that SSL is associated with a favorable prognosis; however, full recovery may take several months, and dogs presenting with urinary incontinence and higher neurological severity grades are less likely to recover. Finally, our findings suggest that prophylactic treatment against S. lupi may have a protective effect against SSL and is therefore recommended in endemic regions.

Nematode fauna in Canis lupus familiaris and Felis catus in Karakalpakstan and molecular genetic analysis of Toxascaris leonina

The article analyses the current species diversity of nematodes of dogs and cats in Karakalpakstan. Our research team identified 11 species of nematodes in dogs: Trichocephalus vulpis (Froelich, 1789), Dioctophyme renale (Goeze, 1782), Ancylostoma caninum (Ercolani, 1859), Uncinaria stenocephala (Railliet, 1854), Toxascaris leonina (Linstow, 1902), Toxocara canis (Werner, 1782), Spirocerca lupi (Rudolphi, 1809), Physaloptera praeputialis (Linstow, 1888), Rictularia affinis (Jagerskiold, 1904), Dirofiliaria immitis (Leidy, 1856), and Dirofiliaria repens (Railliet et Henry, 1911). The prevalence of infection in the dog population ranged from 8.3% to 45.8%, with the intensity of infection ranging between 1 and 28 individuals. The nematode fauna of cats consisted of 9 species: D. renale , A. caninum , U. stenocephala , T. leonina , T. canis , Ph. praeputialis , R. affinus , D. immits , and D. repens . In this group of animals, the prevalence ranged from 8.3% to 37.6% and the intensity of infection from 1 to 23 individuals. Toxascaris leonina was the predominant helminth species in both cats and dogs. Toxocara canis showed a prevalence of 37.6% and an infection intensity of 4 to 9 individuals in domestic Canidae, and 33.7% and 3-8 individuals in Felis catus . The research team conducted a molecular genetic analysis of T. leonina . The study showed that Toxascaris leonina from dogs differed from the same species of nematodes from cats and w as characterised by two subclades. One clade identified in dogs (PP865013) is close to an isolate from China (MN329693) and Australia (NC023504), and the other one in cats (PP864705) to an isolate from the tiger (China, MW560284). In addition, the isolates are grouped together irrespective of hosts and location and are related to other species from the family Ascarididae .

Sialoadenosis caused by spirocercosis in two dogs from Sri Lanka

AbstractSpirocercosis is a common parasitic disease in dogs in tropical and mediterranean regions of the world caused by the nematode Spirocerca lupi. Some dogs with spirocercosis develop sialoadenosis, a condition identified by non‐inflammatory, painless, bilateral enlargement of the mandibular salivary glands. Development of sialoadenosis in dogs infected with S. lupi occurs as a consequence of neurological stimulation caused by larval migration and oesophageal parasitic nodule formation. This report describes the clinical signs, diagnosis, treatment and the treatment outcome of two dogs diagnosed with sialoadenosis caused by spirocercosis. Phenobarbital therapy is useful to control clinical signs shown by the dogs with sialoadenosis secondary to spirocercosis presented at an early stage of the disease. A more favourable disease outcome is possible when phenobarbital therapy is combined with anti‐parasitic medication effective against S. lupi.

Spirocerca lupi draft genome, vaccine and anthelmintic targets

Spirocerca lupi draft genome, vaccine and anthelmintic targets

Molecular characterization of a novel Spiruromorpha species in wild Chinese pangolin by mitogenome sequence analysis.

Pangolins are susceptible to a variety of gastrointestinal nematodes due to their burrowing lifestyle and feeding habits, and few parasitic nematodes have been reported. Here, a Chinese pangolin with old wounds on its leg and tail was rescued from the Heyuan City, Guangdong Province. The cox1 and SSU rRNA of the worms from the intestine of the Chinese pangolin had the highest sequence identity of 89.58% and 97.95% to the species in the infraorder Spiruromorpha. The complete mitogenome of the worm was further assembled by next-generation sequencing, with a size of 13,708 bp and a GC content of 25.6%. The worm mitogenome had the highest sequence identity of 78.56% to that of Spirocerca lupi, sharing the same gene arrangement with S. lupi and some species in other families under Spiruromorpha. However, the mitogenome between the worm and S. lupi showed differences in codon usage of PCGs, sequences of NCR, and tRNA secondary structures. Phylogenetic analysis showed that the worm mitogenome was clustered with S. lupi in the family Thelaziidae to form a separate branch. However, it is still difficult to identify the worm in the family Thelaziidae because the species in the family Thelaziidae are confused, specifically S. lupi and Thelazia callipaeda in the family Thelaziidae were separated and grouped with species from other families. Thus, the parasitic nematode from the Chinese pangolin may be a novel species in Spiruromorpha and closely related to S. lupi. This study enriches the data on gastrointestinal nematodes in the Chinese pangolin.

Helminth Fauna of Bats in the Rostov Region: Review. 1. Nematoda

Introduction. Bats (Chiroptera) are the least studied group of mammals in many regions of Russia. At the same time, the chiropterans are known to be one of the largest orders of Mammalia, which can act as hosts and carriers of various pathogenic fungi, bacteria and viruses. However, the parasitic fauna of this group of animals is poorly investigated. The study of bat-parasitizing worms has great practical importance, since bats, due to their ancient origin, are a very detached order. Endoparasites, including the chiropteran helminths, have not been previously studied in the Rostov region. According to the available data, the up-to-date research on the bat parasites in Russia has been carried out only in the Saratov region and in the Republic of Mordovia. The aim of this series of articles is to study the helminth species composition parasitizing in chiropterans in the Rostov region. In the first report we present the data on nematodes.Materials and Methods. The materials for the research were the articles from the open access literature databases: PubMed (pubmed.ncbi.nlm.nih.gov), Cyberleninka (cyberleninka.ru), GoogleScholar (https://scholar.google.com ), etc. The main method used was the analysis of the collected data.Results. The authors were the first to reveal that 27 nematode species from 14 genera, 8 families, 4 orders and 2 classes can be found in 15 bat species living in the Rostov region. The numerous Chromadorea class is represented by 21 species, 12 of which are found in Russia.Discussion and Conclusion. The results of the literature sources analysis showed that the largest number of nematode species parasitize in two chiropteran species living in the Rostov region: in the Daubenton's bat (15 species) and in the common noctule (14 species). Only one species has been recorded in the northern bat. Most nematode species parasitize specifically in bats and have a direct life cycle. (e.g., species of the genus Molinostrongylus). For some species, such as Pterygodermatites bovieri and Litomosa spp., the intermediate hosts are arthropods and the definitive hosts are various bat species. For three nematode species: Ascarops strongylina, Physocephalus sexalatus and Spirocerca lupi, bats are the paratenic hosts.

Elucidating Spirocerca lupi spread in the Americas by using phylogenetic and phylogeographic analyses.

Spirocerca lupi is a parasitic nematode of domestic and wild canids of the world. This nematode induces esophageal spirocercosis and may eventually lead to carcinomas, aortic aneurisms, and death of the animal. Two genotypes of S. lupi have been described based on specimens from Europe, Asia, Africa, and Oceania, but no profound analysis has been conducted with S. lupi from the Americas. To study this, S. lupi specimens isolated from domestic dogs from Mexico, Costa Rica, and the United States, were molecularly characterized using 18S rDNA and cox1 fragments. Bayesian inference (BI) phylogenetic trees, Templeton-Crandall-Sing (TCS) haplotype networks and Principal coordinate analysis on nucleotide distances were constructed for each locus separately. In addition, a phylogeographic study using a fragment of the cox1 gene was used to infer the evolutionary history of the genus. BI cox1 trees grouped S. lupi from the Americas in genotype 1, together with Israeli specimens, and showed a high nucleotide identity with those worms. In the TCS network, American specimens clustered next to Israeli S. lupi. Furthermore, the 18S rDNA gene fragment separated Costa Rican worms from African, Asian, and European specimens and other species of the family Spiruridae. Interestingly, the phylogeographic analysis suggested that the origin of S. vulpis was in Europe, and it later diverged into S. lupi that spread first to Africa, then to Asia and finally to the Americas. Therefore, we suggest that the worms from the American continent might have originated from Asia by dispersion of infected intermediate, paratenic or definitive hosts.

INTESTINAL PARASITES IN PECARI TAJACU AND SUS SCROFA DOMESTICUS IN THE CAATINGA FROM SOUTHEASTERN PIAUÍ, BRAZIL.

This study identifies gastrointestinal parasites in the feces of Pecari tajacu (caititu) and Sus scrofa domesticus (domestic pig) in southeastern Piauí, Brazil. The region covers 2 protected areas, Serra da Capivara National Park and Serra das Confusões National Park, and surrounding communities. Fecal samples from 64 animals, 42 from domestic swine and 22 from caititu, collected between 1985 and 2013, were analyzed by optical microscopy. Helminths and/or protozoa were found in 64% of the domestic pig samples and 27% of the caititu samples, totaling 18 morphospecies: Nematoda, Spirurida (2 morphospecies), Trichostrongyloidea, Eimeriidae, Aspidodera sp., Bertiella sp., Metastrongylus sp., Trichostrongylus sp., Moniezia sp., Gongylonema sp., Trichuris suis, Spirocerca lupi, Macracanthorhyncus hirudinaceus, Globocephalus urosubulatus, Strongyloides cf ransomi, Balantioides coli, and Eimeria cf scabra. The highest parasite diversity was obtained in the pig samples, totaling 15 morphospecies, compared to only 6 in caititus, with S. cf ransomi, G. urosubulatus, and S. lupi present in both hosts. We discuss the presence of parasites associated with domestic animals around the Protected Areas and potentially zoonotic parasites close to human communities, which raise concerns about the conservation of wildlife, human health, and livestock in the region.

Spirocerca lupi in the stomach of two Andean foxes (Lycalopex culpaeus) from Chile

The genus Spirocerca includes nematodes that parasitize the stomach and the oesophagus of carnivores, chiefly canids. Herein, we provide new data about the morphological, histopathological, and molecular characterization of Spirocerca sp. in Andean foxes (Lycalopex culpaeus) in Chile. Intact immature worms, identified as Spirocerca sp., were recovered in the lumen of the stomach from two foxes. Histologically, worms morphologically consistent with spirurid nematodes were present within the wall of the stomach and surrounded by nodular areas of inflammation with central necrotic debris. Molecular analysis of the cox1 gene yielded 19 sequences and 5 nucleotide sequence types with 99.95 to 99.98% similarity, being shared between both foxes. Nucleotide similarity ranged from 93.1 (with genotype 2 of S. lupi and S. vulpis) to 95.8% (with genotype 1 of S. lupi), a higher similarity than noted from sequences of S. lupi from an Andean fox from Peru (91.0 to 93.3%). However, the Poisson Tree Processes for species delineation did not support the existence of a new species Spirocerca. Phylogenetic and nucleotide analyses suggest that these specimens belong to a new variant or genotype of S. lupi or to a cryptic species. Whether the presence of the worms in the stomach has to do with genotypic differences in parasites or host or some combination is uncertain. Spirocerca lupi has never been found in Chilean dogs and must be investigated.

Evaluation of a treatment protocol in dogs with intraspinal spirocercosis.

To evaluate the efficiency and safety of a doramectin-based treatment protocol in dogs affected by intraspinal spirocercosis (Spirocerca lupi). Client-owned dogs that were admitted to a veterinary hospital during 2021 to 2022 with acute onset of neurological signs and diagnosed with intraspinal spirocercosis. All dogs underwent complete neurological evaluation, CSF analysis, PCR confirmation of CNS S lupi infection, and follow-up evaluation of at least 6 months. Upon diagnosis, dogs were treated with doramectin at a dose of 400 μg/kg, SC, q 24 h for 3 consecutive days, followed by the same dose once a week for 6 weeks. Prednisone was administered at a dose of 1 mg/kg, PO, q 24 h and tapered every 3 days. Antimicrobial clindamycin was administered at a dose of 12.5 mg/kg, PO, q 12 h for 7 days to reduce the risk of secondary spinal cord infection. Short- and long-term outcomes (1 week to 56 months) were recorded. 8 dogs fulfilled the inclusion criteria, 7 of which presented with neurological deficits and 1 with cervical pain. Initiation of treatment was associated with stopping the deterioration in 7 of 8 dogs. Seven dogs improved and 6 recovered ambulation. One dog was euthanized due to lack of improvement. Six of the recovered dogs were still ataxic on the last follow-up examination at 6 to 56 months. No adverse effects of the drug were noted. Frequent administration of doramectin was found to be safe and effective in preventing neurological deterioration in dogs with intraspinal spirocercosis.

Larvae of Spirocerca lupi and another spirurid species in the same dung beetles: notes on species identification.

Various dung beetle species of the family Scarabaeidae have been reported as intermediate hosts of Spirocerca lupi from different geographical locations, but there has been no data from south-east Asian countries. In the present study in Vietnam, by using morphological and molecular approaches, we identified the third-stage larvae of S. lupi for the first time in two dung beetle species, Catharsius molossus and Copris szechouanicus, adding them as new intermediate hosts of this nematode. In addition, both beetle species were infected with larvae of another spirurid nematode of Physocephalus sp. At large magnifications above 200×, these two spirurid larvae can be differentiated from each other by their body size (1880-2662 vs. 1417-1635 μm) and detailed morphological features of the anterior and posterior ends, such as the length of the buccal cavity, the position of the nerve ring and excretory pore, and tail characters. However, it is difficult to distinguish them at a lower magnification due to their minute size. Moreover, morphometric data of S. lupi larvae vary among reports and the body length may overlap with that of Physocephalus sp., thus, misidentification may occur, indicating the necessity of careful examination for accurate identification. The findings of the present study also supposed that larvae of S. lupi and more spirurid nematodes may be concurrently found in various dung beetle species, including C. molossus and C. szechouanicus, in other south-east Asian countries. Thus, more investigations in various countries should be conducted to identify spirurid larvae from dung beetles in order to fully understand their role as intermediate hosts of S. lupi and other spirurid nematodes.

Espirocercose – uma doença silenciosa – revisão sistemática no período de 2010-2021

Spirocerciasis is a parasitic, chronic, silent and fatal disease caused by Spirocerca lupi, which affects canids, and exceptionally felids. The objective of this report is to record the occurrence of spirocerciasis in dogs/canids reported in Brazil, from 2010 to 2021. The bibliographic research indicated the record of 24 cases in Brazil, with 50% of the cases being recorded in the Southeast region, 42% in the Midwest and 8% in the Northeast. The low number of cases may be associated with the insidious characteristic of the disease, the presence of nonspecific clinical signs, the ability to cause sudden death in the definitive host, due to rupture of an aortic aneurysm, and the difficulty of diagnosis in coproparasitological examination.

Epidemiological study of gastrointestinal helminths among dogs from Northeastern Nigeria: a potential public health concern.

Understanding the epidemiology of canine parasitic infections, gastrointestinal helminthic infections in particular, is crucial for designing an efficient control programs targeted at minimizing the risks of zoonotic transmission. A total of 470 dogs attending veterinary clinics in Northeastern Nigeria were screened for gastrointestinal helminths using standard parasitological techniques. Epidemiological risk factors associated with the canine parasitic infections were assessed using multivariable logistic regression analysis. In total, 77.9% (366/470) of dogs had harboured one or more species of the gastrointestinal helminths: Ancylostoma caninum (40.2%), Toxocara canis (35.1%) Trichuris vulpis (26.6%), Spirocerca lupi (5.7%), Taenia/Echinococcus (12.3%), Dipylidium caninum (10.9%) and Diphyllobothriid ova (2.8%). Female dogs (OR=2.1; p=0.02), local breeds (OR=2.3; p<0.01), younger dogs (OR=3.2; p<0.001), dogs adopted as security guards (OR=1.8; p<0.01) and poor body condition score (OR=3.1; p<0.001) were strongly associated with A. caninum infection. For T. canis and T. vulpis, younger dogs (OR=2.5; p=0.02 and OR=2.3; p<0.01) and poor body condition score (OR=4.2; p<0.001 and OR=2.2; p<0.01) were the strong predictors for infection, whereas female dogs (OR=2.8; p=0.02), younger dogs (OR=4.1; p<0.001) and poor body condition score (OR=4.0; p<0.001) were strongly associated with D. caninum infection in dogs. The results revealed high prevalence of gastrointestinal helminths-some of which have zoonotic potential-among dogs underlying huge public health risk.

Subcutaneous spirocercosis in a dog from Costa Rica and first molecular confirmation of Spirocerca lupi in Central America.

Subcutaneous spirocercosis in a dog from Costa Rica and first molecular confirmation of Spirocerca lupi in Central America.

CHARACTERIZATION OF LESIONS INDUCED BY SPIROCERCA VULPIS (SPIRURIDAE: SPIROCERCIDAE) IN RED FOXES (VULPES VULPES).

Spirocerca lupi infection in dogs (Canis domesticus) is associated with esophageal lesions that may evolve to a neoplastic stage in the form of esophageal sarcoma. In the red fox (Vulpes vulpes) infected with the closely related Spirocerca vulpis, similar lesions may occur in the stomach, but neoplastic forms have not been reported. We characterize Spirocerca vulpis-induced lesions in the fox, using pathology and immunohistochemical (IHC) techniques. Seventy-one out of 163 Spirocerca vulpis-positive red foxes were selected and subjected to histopathological study. Lesions were classified as patchy or diffuse. Ten patchy and 10 diffuse lesion samples were studied using three IHC markers (CD68, CD3, and CD79α for macrophages, T lymphocytes, and B lymphocytes, respectively) and H&E stain for neutrophils and eosinophils. Intensity of necrosis, hemorrhages, and the presence of collagen was also analyzed. Of the S. vulpis-positive red foxes, 96.9% had S. vulpis nodules localized in the gastric area (wall and/or omentum), and 3.1% had nodules in the small intestine. All the samples had a moderate to severe lymphoplasmacytic infiltrate. Mild eosinophil infiltration was observed in both types of lesions, while neutrophil infiltration was significatively higher in the patchy than in the diffuse lesions. Fibrosis with mature collagen fibers was also predominant in the patchy lesions along with the presence of T lymphocytes and macrophages. Both the patchy and diffuse patterns had very few B lymphocytes. These findings suggest that the diffuse form is an earlier stage of the lesion, which eventually evolves into patchy forms. Neoplastic forms were not seen. Although more studies are necessary, this study describes the lesions, characterizes the inflammatory infiltrates, and establishes a possible evolution of the different pathological forms of S. vulpis infection in the red fox.

Helminth infections in dogs in Phu Tho Province, northern Vietnam

Helminth infections in dogs in Phu Tho Province, northern Vietnam

Occurrence and Pathology of Fatal Oesophageal Spirocercosis in a Doberman Dog

Spirocercosis is an important disease affecting primarily the domestic and wild canines. The disease is caused by the nematode, Spirocerca lupi. The parasites are potentially lethal and live inside nodules formed within the oesophageal wall of dogs. This study reports the findings observed during the necropsy conducted on the carcass of a ten year old female Doberman dog at the Department of Veterinary Pathology, KNP College of Veterinary Science, Shirwal. The dog had a history of anorexia and vomition and was treated for gastritis by the local veterinarian before it succumbed. Systemic necropsy revealed a large esophageal tumour like nodule at the distal oesophageal wall. The inner cavity of the nodule had six, 2 cm to 6 cm long reddish spirally coiled nematodes embedded in muco-purulent exudate. Histopathology of the nodule showed the presence of an inflammatory reaction consisting mostly of plasma cells and hemosiderin laden macrophages. The nematodes were identified as S. lupi based on its morphological characteristics.