Synergistic effects of using sodium hypochlorite (bleach) and desiccation in surface inactivation for Toxocara spp.

Toxocara cati and T. canis are parasitic nematodes found in the intestines of cats and dogs respectively, with a cosmopolitan distribution, and the potential for anthropozoonotic transmission, resulting in human toxocariasis. Spread of Toxocara spp. is primarily through the ingestion of embryonated eggs contaminating surfaces or uncooked food, or through the ingestion of a paratenic host containing a third-stage larva. The Toxocara spp. eggshell is composed of a lipid layer providing a permeability barrier, a chitinous layer providing structural strength, and thin vitelline and uterine layers, which combined create a biologically resistant structure, making the Toxocara spp. egg very hardy, and capable of surviving for years in the natural environment. The use of sodium hypochlorite, household bleach, as a disinfectant for Toxocara spp. eggs has been reported, with results varying from ineffective to limited effectiveness depending on parameters including contact time, concentration, and temperature. Desiccation or humidity levels have also been reported to have an impact on larval development and/or survival of Toxocara spp. eggs. However, to date, after a thorough search of the literature, no relevant publications have been found that evaluated the use of sodium hypochlorite and desiccation in combination. These experiments aim to assess the effects of using a combination of desiccation and 10% bleach solution (0.6% sodium hypochlorite) on fertilized or embryonated eggs of T. cati, T. canis, and T. vitulorum. Results of these experiments highlight the synergistic effects of desiccation and bleach, and demonstrate a relatively simple method for surface inactivation, resulting in a decrease in viability or destruction of T. cati, T. canis and T. vitulorum eggs. Implications for these findings may apply to larger scale elimination of ascarid eggs from both research, veterinary, and farming facilities to mitigate transmission.

Comparison of extracellular vesicle isolation methods for the study of exosome cargo within Toxocara canis and Toxocara cati excretory secretory (TES) products.

Toxocara is a genus of nematodes, which infects a variety of hosts, principally dogs and cats, with potential zoonotic risks to humans. Toxocara spp. larvae are capable of migrating throughout the host tissues, eliciting eosinophilic and granulomatous reactions, while surviving for extended periods of time, unchanged, in the host. It is postulated that larvae are capable of altering the host's immune response through the release of excretory-secretory products, containing both proteins and extracellular vesicles (EVs). The study of EVs has increased exponentially in recent years, largely due to their potential use as a diagnostic tool, and in molecular therapy. To this end, there have been multiple isolation methods described for the study of EVs. Here, we use nanoparticle tracking to compare the yield, size distribution, and % labelling of EV samples acquired through various reported methods, from larval cultures of Toxocara canis and T. cati containing Toxocara excretory-secretory products (TES). The methods tested include ultracentrifugation, polymer precipitation, magnetic immunoprecipitation, size exclusion chromatography, and ultrafiltration. Based on these findings, ultrafiltration produces the best results in terms of yield, expected particle size, and % labelling of sample. Transmission electron microscopy confirmed the presence of EVs with characteristic cup-shaped morphology. These findings can serve as a guide for those investigating EVs, particularly those released from multicellular organisms, such as helminths, for which few comparative analyses have been performed.

Cestodiasis in 2 Puerto Rican crested anoles.

Two adult male Puerto Rican crested anoles (Anolis cristatellus cristatellus) housed in a research facility were presented with debilitation and were euthanized. On autopsy, anole 1 had a large cystic white structure in the left pelvic limb, which protruded through the ruptured epidermis, and a large, poorly demarcated swelling in the right caudal abdomen. Anole 2 had masses in the mid-dorsum, caudal dorsum, left pelvic limb, and tail. These masses contained variably sized cestode larvae, which ruptured into the coelomic cavity. Evaluation of the larvae revealed a thickened and wrinkled anterior end, with a cleft-like invagination, consistent with either a plerocercoid sparganum or a tetrathyridium. Histologically, several cestode larvae were contained in the body wall of both anoles. These were up to 650 µm in diameter, with a thin tegument and a spongy parenchyma. The spongy parenchyma contained numerous, up to 30 µm diameter, sharply demarcated, basophilic-to-black structures (calcareous corpuscles). There was pneumonia and hepatitis in anole 2, suggestive of potential secondary infection subsequent to immunosuppression. Molecular amplification of the cytochrome C oxidase subunit 1 revealed 100% homology for the COX1 gene of the diphyllobothriid tapeworm Spirometra erinaceieuropaei, also known as Spirometra mansoni.

Multicenter evaluation of the Vetscan Imagyst system using Ocus 40 and EasyScan One scanners to detect gastrointestinal parasites in feces of dogs and cats.

The Vetscan Imagyst system (Zoetis) is a novel, artificial intelligence-driven detection tool that can assist veterinarians in the identification of enteric parasites in dogs and cats. This system consists of a sample preparation device, an automated digital microscope scanner, and a deep-learning algorithm. The EasyScan One scanner (Motic) has had good diagnostic performance compared with manual examinations by experts; however, there are drawbacks when used in veterinary practices in which space for equipment is often limited. To improve the usability of this system, we evaluated an additional scanner, the Ocus 40 (Grundium). Our objectives were to 1) qualitatively evaluate the performance of the Vetscan Imagyst system with the Ocus 40 scanner for identifying Ancylostoma, Toxocara, and Trichuris eggs, Cystoisospora oocysts, and Giardia cysts in canine and feline fecal samples, and 2) expand the assessment of the performance of the Vetscan Imagyst system paired with either the Ocus 40 or EasyScan One scanner to include a larger dataset of 2,191 fecal samples obtained from 4 geographic regions of the United States. When tested with 852 canine and feline fecal samples collected from different geographic regions, the performance of the Vetscan Imagyst system combined with the Ocus 40 scanner was correlated closely with manual evaluations by experts. Sensitivities were 80.0‒97.0% and specificities were 93.7‒100.0% across the targeted parasites. When tested with 1,339 fecal samples, the Vetscan Imagyst system paired with the EasyScan One scanner successfully identified the targeted parasite stages; sensitivities were 73.6‒96.4% and specificities were 79.7‒100.0%.

Evaluation of Fecal Egg Count Tests for Effective Control of Equine Intestinal Strongyles.

The American Association of Equine Practitioners strongly advocates evidence-based intestinal strongyle control in horses. It recommends targeted treatment of all heavy egg shedders (>500 eggs per gram (EPG) of feces), while the low shedders (0-200 EPG) are left untreated. As 50-75% of adult horses in a herd are low shedders, preventing them from unnecessary anthelmintic exposure is critical for tackling resistance. There are various fecal egg count (FEC) techniques with many modifications and variations in use, but none is identified as a gold standard. The hypothesis of the study was that the diagnostic performance of 12 commonly used quantitation methodologies (three techniques with four variants) differs. In this regard, method comparison studies were performed using polystyrene beads as proxy for intestinal strongyle eggs. Mini-FLOTAC-based variants had the lowest coefficient of variation (CV%) in bead recovery, whereas McMaster variants had the highest. All four variants of Mini-FLOTAC and the NaNO3 1.33 specific gravity variant of modified Wisconsin followed a linear fit with R2 > 0.95. In contrast, the bead standard replicates for modified McMaster variants dispersed from the regression curve, causing a lower R2. The Mini-FLOTAC method seems less influenced by the choice of floatation solution and has better repeatability parameters and linearity for bead standard recovery. For FEC tests with high R2 (>0.95) but that underestimated the true bead count, a correction factor (CF) was determined to estimate the true count. Finally, the validity of CF was analyzed for 5 tests with R2 > 0.95 to accurately quantify intestinal strongyle eggs from 40 different horses. Overall, this study identified FEC methodologies with the highest diagnostic performance. The limitations in standardizing routine FEC tests are highlighted, and the importance of equalization of FEC results is emphasized for promoting uniformity in the implementation of parasite control guidelines.

Vector-borne and other pathogens of potential relevance disseminated by relocated cats.

Large populations of unowned cats constitute an animal welfare, ecological, societal and public health issue worldwide. Their relocation and homing are currently carried out in many parts of the world with the intention of relieving suffering and social problems, while contributing to ethical and humane population control in these cat populations. An understanding of an individual cat's lifestyle and disease status by veterinary team professionals and those working with cat charities can help to prevent severe cat stress and the spread of feline pathogens, especially vector-borne pathogens, which can be overlooked in cats. In this article, we discuss the issue of relocation and homing of unowned cats from a global perspective. We also review zoonotic and non-zoonotic infectious agents of cats and give a list of practical recommendations for veterinary team professionals dealing with homing cats. Finally, we present a consensus statement consolidated at the 15th Symposium of the Companion Vector-Borne Diseases (CVBD) World Forum in 2020, ultimately to help veterinary team professionals understand the problem and the role they have in helping to prevent and manage vector-borne and other pathogens in relocated cats.

Elimination of probable praziquantel-resistant Dipylidium caninum with nitroscanate in a mixed-breed dog: a case report.

BACKGROUND: Praziquantel is the drug of choice for treating the tapeworm Dipylidium caninum in dogs; however, resistance is possible, and regular, non-targeted administration of praziquantel may select for anthelminthic-resistant populations. METHODS: The zinc sulfate fecal floatation procedure was conducted. Gross visualization was used to identify Dipylidium spp. segments, and capsule endoscopy was used to visualize adult tapeworms within the intestinal tract. RESULTS: An 18-month-old spayed female terrier mix was presented due to diarrhea, hematochezia and weight loss. The dog received appropriate anthelmintic therapy for Giardia spp., Ancylostoma spp. and Dipylidium spp. The dog's clinical signs resolved, and elimination of Ancylostoma spp. was confirmed by subsequent fecal analysis. However, Dipylidium spp. segments were repeatedly present in the stool. Observation of the segments confirmed the presence of adult Dipylidium spp in feces. Treatment with praziquantel and epsiprantel were unsuccessful in eliminating the organism but was apparently successful in flea prevention. A single dose of nitrosconate was administered and eliminated Dipylidium spp. infection in the dog. CONCLUSIONS: Nitrosconate can be an effective treatment for praziquantel-resistant dipylidiasis in dogs. The novel application of capsule endoscopy confirmed the anthelmintic efficacy of this treatment.

First paleoparasitological evidence of Muellerius sp. in sheep or goat dated to the Sasanian Empire (500 CE) in ancient Iran.

A fecal pellet was recovered in an ancient salt mine in Chehrabad located in western Iran (36.55° N, 47.51° E). Based on prior publications showing the success of the salt mine's environment to preserve various life forms, it was decided to try and ascertain whether this faex contained any parasites of paleoparasitologic interest. The rehydration involved placing the pellet in an aqueous solution of 0.5% trisodium phosphate for a week, followed by the examination of aliquots of the entire rehydrated sample on a total of 153 microscope slides. The examination of the rehydrated material revealed the presence of two larval nematodes; there were no eggs or oocysts recovered. The larvae were photographed and measured, and the decision was made not to submit the two larvae to grinding and DNA extraction for molecular diagnostics due to their excellent state of preservation. The larvae were identified as first-stage larvae that appear to represent the genus Muellerius. Herein are reported the finding of two first-stage larvae of Muellerius nematodes (Metastrongyloidea, Protostrongylidae) from the rehydrated fecal pellet collected in a Chehrabad salt mine from the era of the Sasanian Empire.

Further data on the distribution of Dirofilaria spp. in the Czech Republic in dogs.

Based on previously published data, the Czech Republic is regarded an endemic country of the onchocercid nematodes Dirofilaria immitis (Leidy, 1856) and Dirofilaria repens Railliet et Henry, 1911. Nevertheless, while cases of D. repens are commonly reported from dogs in South Moravia, no recent records of D. immitis are available. Therefore, the present study was performed to clarify the occurrence of both species of Dirofilaria Railliet et Henry, 1910. Blood samples of 551 dogs sampled during 2015 and 2016 were analysed microscopically for presence of microfilariae and blood sera were examined by IDEXX SNAP® 4Dx® test (IDEXX, USA). DNA from blood of microscopically positive dogs was extracted and PCR protocol amplifying fragment of cytochrome c oxidase I (COI) gene was performed; PCR products were then sequenced. All dogs from the Bohemian part of the Czech Republic were negative. The prevalence of D. repens in the Moravian region was 5.7 % (27/476). BLAST analyses of obtained sequences confirmed the presence of D. repens (99-100% identical to KX265049). All sampled animals showed a negative result for D. immitis antigen in IDEXX SNAP® 4Dx® test. Our study confirmed the previously reported occurrence of D. repens in South Moravia and revealed its spreading from the epicentre to the north and west. PCR with subsequent sequencing together with negative results for D. immitis antigen in IDEXX SNAP® 4Dx® test revealed only D. repens infection. A previously published autochthonous infection of dogs with D. immitis in South Moravia was not confirmed.

Feline ophthalmomyiasis externa caused by Cuterebra larvae: four cases (2005-2020).

CASE SERIES SUMMARY: Described are four cats diagnosed with ophthalmomyiasis externa caused by Cuterebra larvae. Medical records were retrospectively reviewed to identify cats with ophthalmomyiasis externa between 2005 and 2020 at Cornell University Hospital for Animals. Signalment, history, clinical and diagnostic findings, treatment and outcome were recorded. All cats were young (< 3 years of age), had outdoor access and were initially examined during the summer months. All cases had unilateral disease with the right eye affected. Two cases had nictitating membrane lesions and two had orbital disease. Concurrent superficial corneal ulceration was present in three cats. Two cats suffered from pyrexia, suspected secondary to inflammation from the larval infestation. Successful larval removal was performed in all cats, which resulted in improvement of discomfort and clinical signs. A corneal ulcer persisted in one cat, which was lost to follow-up prior to ulcer resolution. Parasite identification confirmed Cuterebra species infestation in all cases. RELEVANCE AND NOVEL INFORMATION: To the authors' knowledge, this is the first report of feline ophthalmomyiasis externa caused by Cuterebra species. Parasite removal was successful in restoring comfort and resolving clinical signs in all cats with adequate follow-up information.

Prevalence of endoparasitic and viral infections in client-owned cats in metropolitan Bangkok, Thailand, and the risk factors associated with feline hookworm infections.

The prevalence of enteric parasites in cats in metropolitan Bangkok has not been updated in over 13 years. The main objectives of this study include updating the prevalence of endoparasitism in client-owned cats, status of retroviral infections and determining the association between feline hookworm infection and possible risk factors. A total of 509 fecal samples were collected from client-owned cats in 2014-2015 and examined by a wet fecal mount technique. If additional sample remained, a PBS-ethyl acetate sedimentation was done (n = 229), and ZnSO4 centrifugal flotation was also performed if there was sufficient remaining sample (n = 105). At least one parasite was observed in 32.0% (163/509) of cats, with Ancylostoma being the most common intestinal parasite detected in 21.6% (110/509) of cats. Other parasitic infections detected by fecal examinations included Toxocara (6.9%; 35/509), Platynosomum (3.7%; 19/509), Cystoisospora (3.5%; 18/509), Taenia (2.9%; 15/509), Spirometra (1.6%; 8/509), Dipylidium (0.4%; 2/509), and Opisthorchis-like trematode (0.2%; 1/509). Examination for Giardia infection was conducted with the SNAP® Giardia Test, a coproantigen test, on a subset of the fecal samples (233/509) and revealed a positive result on 3.9% (9/233) of samples. Plasma samples were analyzed using the SNAP® Triple Test detecting antigens of Feline Leukemia Virus (FeLV) and Dirofilaria immitis while also detecting antibodies to Feline Immunodeficiency Virus (FIV). Antigens of FeLV and antibodies to FIV were found in 7.1% (19/269) and 5.2% (14/269) of cats, respectively. None of the cats were found to have circulating antigen of Dirofilaria immitis using this test. No association between retroviral and endoparasitic infections was found. From multivariable logistic regression examining associated factors, the ability of cats to access the outdoors (adjusted OR = 3.22, 95% CI; 1.42-7.87) and having tapeworm segments or adult helminths in feces (adjusted OR = 3.31, 95% CI; 1.34-8.21) were significantly associated with the finding of hookworm eggs in feces. This work presents the most up-to-date data on enteric feline parasite prevalence in the metropolitan Bangkok area from which fecal samples were directly collected from cats. Consequently, this study emphasizes that diagnosis of parasitic infections and the routine use of antiparasitic medications should be encouraged by veterinarians and to owners in order to reduce the reservoir of potentially zoonotic parasites.

Spread of anthelmintic resistance in intestinal helminths of dogs and cats is currently less pronounced than in ruminants and horses - Yet it is of major concern.

Anthelmintic resistance (AR) has thus far only rarely been reported for intestinal helminths of dogs and cats, in contrast to parasites of livestock and horses. We highlight possible reasons for this striking and important discrepancy, including ecological, biological and genetic factors and/or intervention regimens of key intestinal helminths concerning both host groups. In view of the current knowledge related to the genetics, mechanisms and principles of AR development, we point at issues which in our view contribute to a comparatively lower risk of AR development in intestinal helminths of dogs and cats. Finally, we specify research needs and provide recommendations by which, based on the available information about AR in ruminant and equine helminths, the development of AR in dog and cat helminths may best be documented, prevented or at least postponed.

Effectiveness of a novel orally administered combination drug product containing milbemycin oxime and lotilaner (Credelio® Plus) for the treatment of larval and immature adult stages of Ancylostoma caninum in experimentally infected dogs.

BACKGROUND: The hookworm, Ancylostoma caninum, is a common and important zoonotic intestinal nematode parasite that infects dogs globally. Both the immature and adult stages of A. caninum ingest large volumes of blood during the feeding process and can cause severe anemia and death in young dogs, even before patent infections can be diagnosed using routine faecal examination methods. Thus, effective treatment of any pre-patent stages of immature hookworms can reduce or eliminate the risk of clinical disease in infected dogs and additionally reduce environmental contamination of eggs and infective larvae. Two randomized, blinded, GCP-compliant, pivotal laboratory dose confirmation studies were conducted to evaluate the effectiveness and safety of a new novel combination of lotilaner and milbemycin oxime tablets (Credelio Plus®) administered orally to dogs experimentally infected with immature (L4 and immature adult [L5]) stages of A. caninum. METHODS: Treatments using the intended global commercial tablet formulation of Credelio Plus were administered in a time frame relative to inoculation with infective larvae so that effectiveness could be assessed against each specific immature stage of A. caninum. In each study, dogs were randomized to one of six (study 1) or four (study 2) treatment groups. Each treatment group contained 8 (study 1) or 10 (study 2) dogs that had been experimentally inoculated with infective A. caninum larvae on day 0 and were dosed once on day 7 or day 11. Enrolled subjects were administered placebo tablets, Credelio Plus tablets, or lotilaner mono tablets to provide minimum dosages of 0.75 mg/kg of milbemycin oxime and 20 mg/kg of lotilaner. All dogs were necropsied 5 days after their respective treatment. All nematodes recovered from the gastrointestinal tract at necropsy were counted by species and stage. RESULTS: For both dose confirmation studies and based on geometric mean worm counts, efficacy of Credelio Plus was ≥ 97.3% against L4 larval stage of A. caninum and ≥ 98.7% against immature adult (L5) A. caninum. CONCLUSIONS: These studies demonstrated that the orally administered Credelio Plus combination tablet was highly efficacious in treating immature (L4 and immature adult [L5]) stages of A. caninum in experimentally infected dogs.

Effectiveness of Credelio® Plus, a novel chewable tablet containing milbemycin oxime and lotilaner for the treatment of larval and immature adult stages of Toxocara canis in experimentally infected dogs.

BACKGROUND: The ascarid, Toxocara canis, is a common and important zoonotic intestinal nematode parasite that infects dogs globally. An effective treatment that kills any pre-patent stages of immature T. canis could additionally reduce or eliminate the development of patent infections that can result in clinical disease in infected dogs and would further reduce environmental contamination of eggs. Two randomized, blinded, GCP-compliant, pivotal laboratory dose confirmation studies were conducted to assess the effectiveness and safety of a new novel combination of lotilaner and milbemycin oxime tablets (Credelio Plus) administered orally to dogs that were experimentally infected with immature (L4 or immature adult [L5]) stages of T. canis. METHODS: The commercial tablet formulation of Credelio Plus® was administered in a time frame relative to inoculation with infective eggs. This allowed for effectiveness to be assessed against each specific immature stage of T. canis. In each study, dogs were randomized and allocated to one of four treatment groups. Each treatment group contained ten dogs that had been experimentally inoculated on Day 0 with infective T. canis eggs and then were dosed once on Day 14 or Day 24 using either placebo tablets or Credelio Plus tablets (IP) to provide minimum dosages of 0.75 mg/kg of milbemycin oxime and 20 mg/kg of lotilaner. All dogs were necropsied 5 or 6 days after their respective treatment. At necropsy, all nematodes recovered from the gastrointestinal tract were counted by species and stage. RESULTS: In both dose confirmation studies using geometric mean worm counts, effectiveness of Credelio Plus was ≥ 98.6% and ≥ 96.8% against L4 larval stage T. canis and immature adult [L5] T. canis in both studies, respectively. CONCLUSIONS: These studies demonstrated that the Credelio Plus combination tablet administered orally to dogs was highly efficacious against experimental infections with L4 and immature adult [L5] stages of T. canis.

SENTINEL COYOTE PATHOGEN SURVEY TO ASSESS DECLINING BLACK-FOOTED FERRET (MUSTELA NIGRIPES) POPULATION IN SOUTH DAKOTA, USA.

As part of the national recovery effort, endangered black-footed ferrets (Mustela nigripes) were reintroduced to the Cheyenne River Sioux Reservation in South Dakota, US in 2000. Despite an encouraging start, numbers of ferrets at the site have declined. In an effort to determine possible causes of the population decline, we undertook a pathogen survey in 2012 to detect exposure to West Nile virus (WNV), canine distemper virus (CDV), plague (Yersinia pestis), tularemia (Francisella tularensis), and heartworm (Dirofilaria immitis) using coyotes (Canis latrans) as a sentinel animal. The highest seroprevalence was for WNV with 71% (20/28) of coyotes testing antibody-positive. Seroprevalence of CDV and plague were lower, 27% and 13%, respectively. No evidence of active infection with tularemia or heartworm was seen in the coyotes sampled. As this study did not sample black-footed ferrets themselves, the definitive cause for the decline of this population cannot be determined. However, the presence of coyotes seropositive for two diseases, plague and CDV, lethal to black-footed ferrets, indicated the potential for exposure and infection. The high seroprevalence of WNV in the coyotes indicated a wide exposure to the virus; therefore, exposure of black-footed ferrets to the virus is also likely. Due to the ability of WNV to cause fatal disease in other species, studies may be useful to elucidate the impact that WNV could have on the success of reintroduced black-footed ferrets as well as factors influencing the spread and incidence of the disease in a prairie ecosystem.

Efficacy of a novel topical combination of esafoxolaner, eprinomectin and praziquantel against Echinococcus multilocularis infections in cats.

NexGard® Combo, a novel topical endectoparasiticide formulation for cats combining esafoxolaner, eprinomectin and praziquantel, for the treatment of internal and external parasite infestations, including arthropods, nematodes and cestodes, was tested for efficacy against induced infections of Echinococcus multilocularis in cats, in two experimental studies. The two studies were performed in the United States with the same E. multilocularis isolate sourced locally. In each study, 20 cats were inoculated intra-gastrically with ~30,000 E. multilocularis protoscoleces three weeks before treatment, then ten cats were randomly allocated to a placebo control group or to the novel formulation treated group. Inoculated cats were treated topically once at the minimum recommended dose of the novel formulation, or with an identical volume of placebo. One week after treatment, cats were humanely euthanized for parasite recovery and count. The efficacy calculation was based on comparison of number of scoleces found in the control group and the novel formulation group. In the two control groups, E. multilocularis scoleces were found in five (range: 30-1025) and eight (range 2-345) cats, the geometric means inclusive of the ten cats per group were 8.9 and 28.8, respectively. In the two novel formulation-treated groups, none of the cats harbored any E. multilocularis scoleces, demonstrating 100% efficacy.

TITLE: Efficacité d'une nouvelle association topique d'esafoxolaner, d'éprinomectine et de praziquantel contre les infections par Echinococcus multilocularis chez les chats. ABSTRACT: NexGard® Combo, une nouvelle formulation d'endectoparasiticide topique pour chats combinant l'esafoxolaner, l'éprinomectine et le praziquantel pour le traitement des infestations parasitaires internes et externes, y compris les arthropodes, les nématodes et les cestodes, a été testé pour son efficacité contre les infections induites par Echinococcus multilocularis chez les chats, dans deux études expérimentales. Les deux études ont été réalisées aux États-Unis avec le même isolat d'E. multilocularis d'origine locale. Dans chaque étude, vingt chats ont été inoculés par voie intra-gastrique avec ~ 30 000 protoscolex d'E. multilocularis trois semaines avant le traitement, puis dix chats ont été répartis au hasard dans un groupe témoin placebo ou dans le groupe traité par la nouvelle formulation. Les chats inoculés ont été traités une fois par voie topique à la dose minimale recommandée de la nouvelle formulation, ou avec un volume identique de placebo. Une semaine après le traitement, les chats ont été euthanasiés sans cruauté pour la récupération et le dénombrement des parasites. Le calcul de l'efficacité était basé sur la comparaison du nombre de scolex trouvés dans le groupe témoin et le groupe de formulation nouvelle. Dans les deux groupes témoins, des scolex d'E. multilocularis ont été trouvées chez cinq (extrêmes: 30 ­ 1025) et huit (extrêmes: 2 ­ 345) chats, les moyennes géométriques comprenant les dix chats par groupe étaient respectivement de 8,9 et 28,8. Dans les deux groupes traités par formulation nouvelle, aucun des chats ne portait de scolex d'E. multilocularis, démontrant une efficacité de 100 %.

Efficacy of a novel topical combination of esafoxolaner, eprinomectin and praziquantel for the prevention of heartworm disease in cats.

NexGard® Combo is a novel topical endectoparasiticide formulation for cats combining the insecticide/acaricide esafoxolaner, the nematodicide eprinomectin and the cestodicide praziquantel. The efficacy of this novel formulation for the prevention of heartworm disease in cats was tested in two experimental studies using an induced infection model and a randomized, blinded, placebo-controlled study design, and two USA isolates of Dirofilaria immitis. In each study, 20 naïve cats were each inoculated sub-cutaneously with 100 third-stage larvae of D. immitis 30 days before treatment. Following randomization to two treatment groups of ten cats, each cat was treated topically once, either with the minimum recommended dose of the novel formulation, or with an identical volume of placebo. Five months after treatment (6 months after infections), the cats were humanely euthanized for parasite recovery and count. Efficacy was calculated by comparison of the numbers of adult D. immitis recovered in the control and in the novel formulation groups. In the control groups of each study, D. immitis were recovered in seven and nine cats (respective worm counts ranges 1-7 and 1-16, respective geometric means 1.6 and 5.1). In both studies, none of the treated cats harbored any D. immitis at necropsy and the calculated efficacy of the novel formulation was 100%. There were no adverse reactions related to treatment with the novel formulation. The results of these two studies demonstrate that a topical NexGard® Combo application at the minimum label dose is well-tolerated and efficacious in preventing heartworm disease in cats.

TITLE: Efficacité d'une nouvelle association topique d'esafoxolaner, d'éprinomectine et de praziquantel pour la prévention de la dirofilariose chez les chats. ABSTRACT: NexGard® Combo est une nouvelle formulation d'endectoparasiticide topique pour chats combinant l'insecticide/acaricide esafoxolaner, le nématodicide éprinomectine et le cestodicide praziquantel. L'efficacité de cette nouvelle formulation pour la prévention de la maladie du ver du cœur (dirofilariose) chez les chats a été testée dans deux études expérimentales utilisant un modèle d'infection induite et une conception d'étude randomisée, en aveugle et contrôlée par placebo, et deux isolats américains de Dirofilaria immitis. Dans chaque étude, vingt chats naïfs ont chacun été inoculés par voie sous-cutanée avec 100 larves de troisième stade de D. immitis 30 jours avant le traitement. Après randomisation dans deux groupes de traitement de dix chats, chaque chat a été traité par voie topique une fois, soit avec la dose minimale recommandée de la nouvelle formulation, soit avec un volume identique de placebo. Cinq mois après le traitement (6 mois après les infections), les chats ont été euthanasiés sans cruauté pour la récupération et le dénombrement des parasites. L'efficacité a été calculée en comparant les nombres de D. immitis adultes collectés dans le groupe contrôle et dans le groupe ayant reçu la nouvelle formulation. Dans les groupes témoins de chaque étude, D. immitis a été trouvé chez sept et neuf chats (les nombres de vers respectifs variaient de 1 à 7 et de 1 à 16, les moyennes géométriques respectives étaient 1,6 et 5,1). Dans les deux études, aucun des chats traités ne présentait de D. immitis lors de l'autopsie et l'efficacité calculée de la nouvelle formulation était de 100%. Il n'y a eu aucun effet indésirable lié au traitement avec la nouvelle formulation. Les résultats de ces deux études démontrent qu'une application topique de NexGard® Combo à la dose minimale indiquée sur l'étiquette est bien tolérée et efficace pour prévenir la dirofilariose chez les chats.