SNAP 4Dx Plus Research Articles

TRP36-ELISA for E. canis detection: Concordance with TaqMan real-time PCR and point-of-care testing

Ehrlichia canis, a widely distributed tick-borne pathogen, requires prompt and accurate diagnosis for effective management. Real-time PCR serves as the reference standard for diagnosing E. canis infection, whereas serological tests are crucial for detecting antibody responses indicative of infection or post-exposure status. Early detection during the acute phase of the disease is essential for optimal treatment and recovery. E. canis Tandem Repeat Protein 36 (TRP36) elicits early acute phase responses. We developed an enzyme-linked immunosorbent assay (ELISA) using recombinant TRP36 to detect IgM and IgG antibodies against E. canis. We assessed the diagnostic agreement, sensitivity, and specificity of the rTRP36-ELISA and a commercial test kit (SNAP 4Dx Plus Test) with TaqMan Real-time PCR (qPCR) using the NCSS 2023 program version 23.0.1. Leftover serum samples from 32 dogs at the Veterinary Teaching Hospital were randomly selected and examined for E. canis infection using qPCR, rTRP36-ELISA, and SNAP 4Dx Plus Test. qPCR detected positive results in 12 (37.5 %), whereas ELISA and SNAP 4Dx Plus detected positive results in 10 (31.25 %) and 13 (40.62 %), respectively. Moderate agreement (κ = 0.545) was observed between rTRP36-ELISA and qPCR, and fair agreement (κ = 0.379) between SNAP 4Dx Plus and qPCR. Substantial agreement (κ = 0.79) was found between rTRP36-ELISA and SNAP 4Dx Plus. Compared to qPCR, the sensitivity and specificity of rTRP36-ELISA were 70 % and 77.27 %, respectively, compared to 53.85 % and 73.86 %, respectively, for SNAP 4Dx Plus. Our findings suggest that TRP36 is a promising antigen for E. canis serodiagnosis, potentially improving sensitivity and specificity.

Evaluation of the Veterinary IDEXX SNAP 4Dx Plus Test for the Diagnosis of Lyme Disease in Humans.

Background: Lyme disease, caused by infection with Borrelia burgdorferi, is the most common vector-borne disease in the United States. The standard two-tier testing (STTT) algorithm suffers from low sensitivity, misinterpretation, and long turnaround time, preventing timely detection and treatment. To address these challenges, we hypothesized that the canine point-of-care (PoC) SNAP 4Dx Plus test used to detect Borrelia burgdorferi antibodies could be employed for human diagnosis. Materials and Methods: The SNAP 4Dx Plus testing was conducted in accordance with the manufacturer's instructions, with results read by manual inspection. All analyses were conducted using R version 4.3.1, and agreement between the PoC assay and the STTT was assessed using kappa statistics with GraphPad software. Results: We included 102 previously-tested human serum samples, of which 19 samples (18.6%) were STTT positive. Compared to the STTT, the SNAP 4Dx Plus test demonstrated a low sensitivity of 0.16 (95% CI 0.03 to 0.40). Conclusion: Overall, our results do not support the use of the SNAP 4Dx Plus LD assay for the diagnosis of human Lyme disease. Differences in antibody concentrations between human and canine samples may partly explain our findings.

Idiopathic Immune Mediated Haemolytic Anaemia (IMHA) in a 2.5-Month-old Puppy: A Case Report

Background: A 2.5-month-old puppy was presented to the Veterinary Clinical Complex of the College of Veterinary Sciences and AH, Jalukie, Nagaland with a complaint of emesis for one week, inappetence, icterus of the lower abdominal area and other visible mucous membrane. Detailed clinical history was collected and clinical examination was conducted. Methods: 4 ml blood peripheral blood was collected from the cephalic vein in the Lev-Lock blood clot activator vacutainer to harvest serum for biochemical analysis. Another 2 ml of whole blood was also collected in Lev-Lock K3 EDTA vacutainer for complete blood count, blood smear examination for blood parasites, morphological changes in the RBC and IDEXX SNAP 4Dx Plus test kit was also used for diagnosis of the blood parasites test. Result: Peripheral blood smear examination and IDEXX SNAP 4Dx Plus test were found to be negative for blood parasites, but spherocytosis could be observed in the blood smears. A complete blood count (CBC) examination revealed severe anaemia of macrocytic normochromic type, neutrophilic leucocytosis and thrombocytopenia. Serum biochemistry revealed a decrease in blood urea nitrogen (BUN) and creatinine with normal alanine transaminase (ALT). Treatment with whole blood transfusion, corticosteroid and other supportive therapy was successful in this case. Based on the clinical presentation, laboratory findings and its response to the treatment with prednisolone, it was diagnosed as an idiopathic immune-mediated haemolytic anaemia (IMHA) with an extravascular mechanism of haemolysis. A follow-up review after 1 year and 4 months post-treatment reported that the dog was still alive and healthy.

Comparative evaluation of Borrelia burgdorferi antibody detection between the VetScan Flex4 and SNAP 4Dx Plus

Two studies were developed to compare Borrelia burgdorferi antibody detection between the VetScan Flex4 and SNAP 4Dx Plus tests. The objective of the first study was to evaluate the diagnostic sensitivity (Se) and specificity (Sp) of VetScan Flex4 and SNAP 4Dx Plus B. burgdorferi results using field sourced samples compared to a Western Blot reference method. The sensitivity and specificity of VetScan Flex4 were 81.9 % (95 % CI: 71.9 %-89.5 %) and 89.3 % (95 % CI: 85.2 %-92.9 %) respectively, and SNAP 4Dx Plus's sensitivity and specificity were 80.7 % (95 % CI: 70.6 %-88.6 %) and 92.8 % (95 % CI: 89.1 %-95.5 %) respectively. When comparing VetScan Flex4 and Snap 4Dx Plus, the Simple Kappa Coefficient estimate was 0.76 (95 % CI: 0.69-0.84) indicating substantial agreement between the two methods. McNemar's Test revealed concordance between the two methods was not statistically significant (P = 0.05). The objective of the second study was to evaluate whether VetScan Flex4 differentiates between B. burgdorferi antibodies derived from infection versus vaccination with commonly used canine Lyme vaccines. The sensitivity and specificity of the VetScan Flex4 in differentiating canine Lyme vaccination from infection with Borrelia burgdorferi were 100 % (Se 95 % CI: 78.2 %-100 %; Sp 95 % CI: 91.2 %-100 %). In conclusion, the VetScan Flex4 is a reliably sensitive and specific point-of-care test that is similar to Snap 4Dx Plus, can differentiate between infection and Lyme vaccination, and can be utilized by veterinarians for Lyme disease diagnosis and surveillance of B. burgdorferi exposure.

Occurrence and hematological aspects of dogs with Canine Monocytic Ehrlichiosis

Canine monocytic ehrlichiosis (CME) is an infectious disease caused by a gram-negative bacterium of the genus Ehrlichia spp., a monocyte parasite that leads to thrombocytopenia, anemia, hyporexia, apathy, pale mucous membranes, among others. The etiological agent is distributed worldwide, but there is a greater incidence and considerable prevalence in places with temperate climates due to the high presence of the tick vector Rhipicephalus sanguineus. In Brazil, the number of cases of this disease appears to have increased in many regions, due to several factors, but more studies are still needed regarding the prevalence in various regions. In view of the aforementioned points, this retrospective study aimed to address the findings of the clinical and laboratory evaluation of 43 medical records with the definitive diagnosis of canine monocytic ehrlichiosis, in naturally infected dogs, treated at HOVET - UFES, during the period of June 2017 to September 2023, in order to discuss and relate the findings found with current literature, as well as report the occurrence of this disease. For this, we used the clinical and laboratory records of dogs that showed positivity in the SNAP 4Dx Plus® rapid test and/or in blood smears, and presented Ehrlichia spp. morulae. in leukocytes. Simultaneously, clinical data, blood count findings and biochemical test results were prepared in figures, tables and organizational charts. Subsequently, with the information and results found, descriptive analysis of the data was used to demonstrate the occurrence through percentages. The most frequent clinical and laboratory changes were the presence of ticks, hyporexia, lymphadenomgelia, apathy, pale mucous membranes, thrombocytopenia, normocytic normochromic anemia, lymphopenia and hypoalbuminemia. Therefore, it is concluded that it is essential to report the occurrence of Ehrlichia sp. in dogs, as well as knowing the main clinical and laboratory changes mentioned so that it is possible to assist in the early identification of canine monocytic ehrlichiosis.

Prevention of heartworm infection in dogs using a combination of moxidectin, imidacloprid and praziquantel: evidence from a randomized clinical trial.

The aim of this study was to evaluate the efficacy of a topical combination of moxidectin 3.5%, imidacloprid 10% and praziquantel 10% for the prevention of Dirofilaria immitis (Leidy, 1856) infection in dogs. For this purpose, a randomized and controlled clinical trial was conducted between August 2021 and October 2022, in the municipality of Goiana, state of Pernambuco, north-eastern Brazil, where heartworm is highly prevalent. Of the 213 dogs initially sampled (baseline), 68 (31.9%) were positive for adult antigens (SNAP 4Dx Plus, Idexx) and/or microfilariae (modified Knott's test). On day 0, 140 negative dogs were randomly included in the treatment and control groups, 70 animals each. During the study, 60 dogs (34 treated and 26 untreated) were removed for different reasons. At the end of the study (day 360 ± 2), 36 treated and 44 untreated were sampled and included in the efficacy calculation. The efficacy against the development of adults and microfilariae was 84.7%, with only one treated dog being positive for adult antigens but negative for microfilariae. On the other hand, eight untreated dogs were positive for adultantigens and/or microfilariae, resulting in a significant difference in the number of positives between groups (Chi-square test = 4.706, df = 1, P = 0.0301). Remarkably, the efficacy against the appearance of D. immitis microfilariae was 100% (i.e., all treated dogs negative) and three untreated dogs were positive for microfilariae. The topical combination of moxidectin 3.5%, imidacloprid 10% and praziquantel 10% significantly reduced the risk of D. immitis infection in treated dogs as compared with untreated dogs, in a highly endemic area in north-eastern Brazil.

A second-generation, point-of-care immunoassay provided improved detection of Anaplasma and Ehrlichia antibodies in PCR-positive dogs naturally infected with Anaplasma or Ehrlichia species.

A validated second-generation SNAP 4Dx Plus (Idexx) incorporates new peptides for improved detection of antibodies against Anaplasma and Ehrlichia tick-borne pathogens in dogs. We compared the first- and second-generation SNAP 4Dx Plus using dogs naturally infected with Anaplasma or Ehrlichia species, or dogs seroreactive by an E. canis indirect fluorescent antibody test (IFAT). The second-generation immunoassay was more sensitive than the first-generation for dogs infected with A. phagocytophilum (51.1% and 29.2%, respectively), A. platys (63.6% and 35.3%, respectively), E. canis (96.2% and 88.3%, respectively), or E. ewingii (73.7% and 70.8%, respectively), and for dogs seroreactive by E. canis IFAT (87.3% and 83.9%, respectively). The second-generation immunoassay detected significantly more Anaplasma- or Ehrlichia-infected dogs that were Anaplasma (p < 0.001) or Ehrlichia (p = 0.031) seroreactive, respectively, than did the first-generation test. When Ehrlichia seroreactivity by E. canis IFAT and both immunoassays was compared, significantly more E. canis-infected dogs were seroreactive by E. canis IFAT than the first-generation (p = 0.006) but not the second-generation (p = 0.125) immunoassay. Significantly more E. ewingii-infected dogs were seroreactive by the first- (p = 0.011) and second-generation (p = 0.049) immunoassays than the E. canis IFAT. Medical records available for 7 dogs that were Anaplasma seroreactive by the second-generation but not the first-generation immunoassay revealed case management decisions that might have been different with an immediate anaplasmosis diagnosis, including earlier doxycycline therapy and less hospitalization. The second-generation SNAP 4Dx Plus test offered improved serologic detection of Anaplasma and Ehrlichia in naturally infected dogs.

EFFECTIVE DIAGNOSTIC TECHNIQUES IN BORRELIA BURGDORFERI INFESTATION IN DOGS

Borreliosis or Lyme disease is a disease transmitted by ixodidae ticks during feeding on blood (Ixodes pacificus and Ixodes scapularis in the USA, Ixodes persulcatus in Asia, Ixodes ricinus in Europe) and is widespread in the entire northern hemisphere. In Romania, the geographic distribution and prevalence of Borrelia burgdorferi sensu lato was 1.4% in 41 counties, with a prevalence between 0.75–18.8%. B. burgdorferi sensu lato. had a prevalence of 3.8%, being found inside ticks in 55 of 183 localities. Successful treatment and full recovery can only be achieved through early diagnosis. The clinical and serologic diagnosis of Lyme disease is particularly difficult because of the phenotypic heterogeneity within and among spirochete species. A case study is presented in this paper: an eight-year-old male Yorkshire terrier dog, which was diagnosed positive for Lyme disease, based on a test which uses a peptide called C6 and which comes from the VlsE protein of B. burgdorferi, used to detect antibodies in dogs. The results demonstrate the reliability of the commercial SNAP 4Dx Plus Test for B. burgdorferi, which uses C6 to differentiate antibodies produced by natural infection from antibodies formed after vaccination. In addition, using real-time PCR, the diagnosis was negative, confirming the results from the literature, according to which the PCR technique is only recommended for research, the positivity percentage being low, especially when the sample is blood (0.1%). We conclude that the tests for the detection of antibodies specific to Lyme disease are recommended and useful.

Prevalence of Anaplasma phagocytophilum and Borrelia burgdorferi infection in horses from Pennsylvania (2017-2019) using antibody and organism-based detection.

To determine the prevalence of Anaplasma phagocytophilum and Borrelia burgdorferi infections in Pennsylvania horses. 271 horses. A survey was conducted with PCR and serology to evaluate anaplasmosis and Lyme disease infections in horses from Pennsylvania that were suspected for tick-borne infection. A phagocytophilum was detected in 19/271 (7.0%) Pennsylvania horses tested by the duplex PCR. B burgdorferi was not detected in any horse blood tested by PCR. Overall, 120/271 (44.3%) horses tested positive for presence of A phagocytophilum antibodies by at least the IDEXX SNAP 4Dx Plus lateral flow immunosorbent (SNAP) or indirect fluorescent antibody (IFA) assay, with 69 (25.5%) testing positive by both SNAP and IFA; 43 (15.9%) tested positive by IFA only, and 8 (3.0%) tested positive by SNAP only. Similarly, 209/271 (77.1%) horses tested positive for the presence of B burgdorferi antibodies by at least 1 test, with 139 (51.3%) testing positive by both SNAP and IFA; 45 (16.6%) tested positive by SNAP only, and 25 (9.2%) tested positive by IFA. Both A phagocytophilum and B burgdorferi are important tick-borne infections. The study provides prevalence data for both A phagocytophilum and B burgdorferi and compares test performance. For serologic detection, IFA detected antibodies to A phagocytophilum in a higher proportion (41.3%) of horses compared to SNAP (28.4%), while SNAP detected antibodies to B burgdorferi in a higher proportion (67.9%) of horses compared to IFA (60.5%). Both diseases showed a high seroprevalence in all areas surveyed.

An Improved Point-of-Care ELISA for the Diagnosis of Anaplasmosis and Ehrlichiosis During the Acute Phase of Tick-Borne Infections in Dogs

Veterinarians often test for serologic evidence of vector-borne infections in sick dogs presenting with clinical signs or to screen for subclinical chronic infections. Additional peptide targets for the detection of antibodies to Anaplasma phagocytophilum, Anaplasma platys, and Ehrlichia canis were added to an existing point-of-care (POC) ELISA test (SNAP 4Dx Plus Test, IDEXX Laboratories, Westbrook, ME). This second-generation, multi-analyte test detects Dirofilaria immitis antigen and antibodies to Anaplasma spp., Borrelia burgdorferi, and Ehrlichia spp. The second-generation test is expected to better meet the needs of practicing veterinarians and their patients. To assess this expectation, the second-generation POC test was evaluated with serum samples from experimentally infected dogs and a broader field population of dogs. Compared to the first-generation test, most dogs experimentally infected with A phagocytophilum (n = 7/8), A platys (n = 4/6), or E canis (n = 4/6) had detectable antibody responses 3-22 days earlier post-infection; these results demonstrated better alignment with polymerase chain reaction (PCR) amplification results and the onset of clinical signs. Using a convenience sample set of 510 sera from both academic and commercial veterinary diagnostic laboratories, the second-generation test had sensitivities greater than 90% for Anaplasma spp. (94.1%), B burgdorferi (95.5%), Ehrlichia spp. (93.4%) and D immitis (98.0%). Specificity ranged from 96.8% - 100% across the four assays. Results from this study demonstrate that the second-generation POC ELISA had an improved ability to detect serologic responses during the acute phase of A phagocytophilum, A platys, and E canis experimental infections. The results from the broader field samples support overall high sensitivity and specificity, consistent with the historical performance of the first-generation POC ELISA test.

Clinical and blood count findings in dogs naturally infected with Dirofilaria immitis.

Dirofilaria immitis is a nematode that infects canids worldwide as well as other mammalian species, including humans. Worms and dogs are well adapted to one another, making dogs the best urban host for the parasite. Nevertheless, 30% of dogs do not sufficiently present microfilaremia, that is, the low larval load impairs transmission by mosquitoes and diagnosis by its detection in the blood samples. Therefore, the canine diagnosis must always include a microfilaria test and serological tests to detect adult worm antigens. To describe the clinical findings in naturally infected dogs in Rio de Janeiro, 34 dogs were included in the study. All dogs were evaluated for history, anamnesis, physical examination, complete blood count (CBC), D. immitis testing for antigens (ELISA test SNAP 4Dx Plus®), and microfilarial burden. The most frequent complaint from the owners was coughing (14.7%, 5/34). The most common CBC finding was eosinophilia (29.4%), followed by thrombocytopenia (26.5%) and neutrophilia (14.7%). Of the 34 animals, 91.2% were microfilaremic, with a mean count of 11.939 microfilaria/mL. Veterinarians working in areas endemic to D. immitis should always undergo screening tests and pulmonary auscultation, and increased expiratory sounds, even in the absence of coughing, can be considered a sign of the disease, along with eosinophilia, thrombocytopenia, and neutrophilia.

Seroprevalence of Anaplasma spp. and Ehrlichia spp. and molecular detection of Anaplasma phagocytophilum and Anaplasma platys in stray dogs in Bosnia and Herzegovina

Stray dogs may be highly exposed to vector-borne pathogens (VBPs), including zoonotic agents, and therefore may pose a high risk of spreading infections to other animals and humans. Among the Anaplasmataceae, Anaplasma phagocytophilum, A. platys and Ehrlichia canis are commonly identified species in dogs in Europe; however, information on the occurrence of these pathogens in canine populations from Bosnia and Herzegovina (B&H) is still lacking. Thus, the aim of this study was to determine the seroprevalence of Anaplasma spp. and Ehrlichia spp. in stray dogs in the Sarajevo region of B&H and to identify A. phagocytophilum, A. platys, E. canis and E. ewingii by molecular techniques. A total of 903 blood samples of stray dogs were screened by SNAP 4Dx Plus Test for the presence of antibodies against A. phagocytophilum/A. platys and E. canis/E. ewingii. Real-time PCR assays were performed for the detection of Anaplasmataceae, A. phagocytophilum, A. platys, E. canis and E. ewingii in seropositive dogs. Antibodies to A. phagocytophilum/A. platys and/or E. canis/E. ewingii were detected in 187 (20.7%) samples. Seroprevalence was highest for A. phagocytophilum/A. platys (184/903, 20.4%). Two dogs had antibodies to E. canis/E. ewingii, while one dog was found to have antibodies to A. phagocytophilum/A. platys and to E. canis/E. ewingii. Forty-eight (25.7%) of the 187 seropositive dogs examined by Real-time PCR were positive for Anaplasmataceae. A. phagocytophilum was detected in 45 (24%) samples, while one sample was positive for A. phagocytophilum and A. platys. Two samples positive for Anaplasmataceae tested negative in the species-specific PCRs. E. canis or E. ewingii could not be detected in any of the Ehrlichia-seropositive dogs. These findings highlight the need for dog health monitoring, improving the health and welfare of stray dog population, and establishment of effective surveillance systems to combat VBDs.

Infection with Dirofilaria immitis and Other Infections in Cats and Dogs from Rio de Janeiro, Brazil: The Need for Prophylactic Enforcement.

Dirofilaria immitis, a mosquito-borne nematode that primarily infects dogs, can equally infect cats. Although there have been numerous studies on canine heartworm prevalence in Brazil, there have been few studies on feline infections. Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are both life-threatening retroviruses transmitted directly between cats. Infections with Ehrlichia spp. and Anaplasma spp. are highly prevalent among dogs in Brazil, with Rhipicephalus sanguineus being the main vector for both bacteria. This study aimed to gather information on these infections among dogs and cats in the metropolitan area of Rio de Janeiro by performing rapid point-of-care tests for prophylactic enforcement. Surplus samples of serum or plasma from private laboratories were tested by enzyme-linked immunosorbent assay (ELISA) (SNAP Feline Triple Test or SNAP 4Dx Plus Test). The prevalence of heartworm disease was 7% among dogs and 0.9% among cats, the latter being 12.9% of the former. The prevalence of FIV and FeLV was 4.3 and 11.9%, respectively. Among dogs, the seroprevalence of Ehrlichia spp. and Anaplasma spp. was 27.1 and 9.8%, respectively, and Borrelia burgdorferi was not detected. Given that such infections circulate among pets, prophylactic measures should be encouraged by small animal practitioners.

Incidence of Dirofilaria immitis and Leishmania infantum infections in sheltered dogs from Southern Italy.

Leishmania infantum and Dirofilaria immitis are among the most important vector-borne pathogens in Europe, affecting animal and human health. In endemic areas, the epidemiology of both infections is conditioned by abundance of vectors and chemoprophylaxis measures. However, knowledge on the incidence of heartworm (HW) and Leishmania infections occurring in sympatry is still scant. Thus, this study aimed to evaluate the incidence of both infections in two dog shelters from southern Italy, which represent hotspots for these two diseases. In June and in October 2020, all dogs that previously scored negative for L.infantum (n=111, site 1; n=70, site 2) and D. immitis (n=58, site 1; n=61, site 2) in 2019 were tested for the estimation of the incidence of both infections. Anti-L. infantum IgG was detected by immunofluorescence antibody test, whereas D. immitis infection was diagnosed by modified Knott's test, SNAP 4Dx Plus test and real-time PCR. The overall D. immitis and L. infantum infection incidence values were both higher in site 2 (i.e. 63.9% and 10%, respectively) than site 1 (i.e. 39.7% and 1.8%, respectively). The dog shelter in site 2 was shown to be more suitable for the development of the mosquito/sand fly populations and, consequently, for the spreading of both parasites representing a potential threat for animal and human health. The high incidence of both infections recorded in this study suggests the need for chemoprophylaxis measures and vector monitoring and control to minimize the risk for animals and humans living in shelters or in their neighbourhoods.

Clinicopathologic evaluation of oral squamous cell carcinoma in a young dog

Canine oral papillomas is a benign tumor of young dogs and caused by papillomavirus. The possible role of papillomavirus infection in the development of oral squamous cell carcinoma has recently been studied, but it has not been elucidated in veterinary medicine yet. One-year-old, mixed, spayed, a female dog was presented with severely disseminated oral lesions, lethargy, and weight loss. Physical examination of the patient revealed severely disseminated oral papillomatous lesions in the entire oral cavity and the complete blood test showed mild non-regenerative anemia and pancytopenia. In addition, the patient was found seropositive by the SNAP 4Dx Plus test for Ehrlichia canis. Histopathologic examination of oral lesions was performed using Hematoxylin and Eosin (HE) staining and immunohistochemistry for p16 antibody which increases in infections caused by papillomavirus. Histopathology revealed the histologic features of oral papilloma in association with squamous cell carcinoma. Cytoplasmic and nuclear positive reactions for p16 protein were observed within the neoplastic cells in the immunohistochemical examination. Thereafter, the dog was treated with combined therapy of vincristine, antibiotic, radiotherapy, and high doses of vitamin C. After long-term treatment, the dog completely recovered from the lesions. In this report, it was aimed to present a possible role of papilloma in the development of oral squamous cell carcinoma with the clinical, histopathological, immunohistochemical findings and treatment procedure.

The Main Clinical Signs and Early Diagnosis of Canine Dirofilariosis in the Veterinary Practice of Farms in the Republic of Armenia

The purpose of the research is to determine the main clinical signs of dirofilariosis in dogs, taking into account the peculiarities of animal exploitation and to analyze the efficacy and convenience of using some diagnostic techniques. Materials and methods. The main clinical signs of dirofilariosis in dogs on the farms of Armenia have been studied. The presence of microfilariae was determined in native smears and using a modified Knott method. We also used the Asan Easy Test Heartworm and SNAP 4Dx Plus Test one-step cassette rapid tests for visual detection of Dirofilaria spp. antigen in blood serum. Results and discussion. 8.5% of dogs in the farms of the Republic of Armenia are infected with Dirofilaria sp. The most infected were dogs aged 5–8 years (75%). The main symptomatic signs of dirofilariosis in dogs were established in the specific conditions of the studied region and the specifics of the specific exploitation of animals. It has been established that the immunochromatographic test systems Asan Easy Test Heartworm and SNAP 4Dx Plus Test for visual detection of canine Dirofilaria spp. antigen in blood serum are the most effective for the diagnosis of dirofilariosis.

Serosurvey of arthropod-borne diseases among shelter dogs in the Cumberland Gap Region of the United States

BackgroundThe Cumberland Gap Region (CGR) of the United States is a natural corridor between the southeastern, northeastern, and midwestern regions of the country. CGR has also many species of ticks and mosquitos that serve as competent vectors for important animal and human pathogens. In this study, we tested dogs from six different animal shelters in the CGR for Rocky Mountain spotted fever (RMSF), anaplasmosis, Lyme disease, canine ehrlichiosis and canine heartworm disease.ResultsSera from 157 shelter dogs were tested for antibodies to RMSF agent, Rickettsia rickettsii, using an indirect immunofluorescence assay. Sixty-six dogs (42.0%) were positive for either IgM or IgG, or both IgM and IgG antibodies to R. rickettsii. Moreover, the same set of sera (n = 157) plus an and additional sera (n = 75) from resident dogs at the same shelters were tested using the SNAP 4Dx Plus. Of 232 dogs tested, two (0.9%) were positive for antibodies to Anaplasma phagocytophilum/A. platys, nine (3.9%) were positive for antibodies to Borrelia burgdorferi, 23 (9.9%) for positive for antibodies to Ehrlichia canis/E. ewingii, and 13 (5.6%) were positive for Dirofilaria immitis antigen. Co-infection with two or more etiologic agents was detected in five animals. Three dogs had antibodies to both B. burgdorferi and E. canis/E. ewingii, and two dogs were positive for D. immitis antigen and antibodies to B. burgdorferi and E. canis/E. ewingii.ConclusionsShelter dogs in the CGR are exposed to a number of important vector-borne pathogens. Further studies are required to ascertain the roles these animals play in maintenance and transmission of these pathogens.

Seroprevalence Rates of Tick-Borne Pathogens in Cats from Southern Bulgaria.

The aim of the present study was to investigate the prevalence rates of the feline tick-borne pathogens (FTBPs)-Borrelia burgdorferi, Ehrlichia canis, and Anaplasma phagocytophilum in stray cats from Southern Bulgaria. Serum antibodies were used to estimate the prevalence of exposure to FTBPs from blood swabs. Of the 100 cat samples tested with in-clinic assay SNAP 4Dx Plus, the overall FTBP seroprevalence was 3% (3/100); with B. burgdorferi-1% (1/100) and E. canis-2% (2/100). This study provides the first evidence of exposure to B. burgdorferi and E. canis in cats from Bulgaria.

Comparison of Diagnostic Tools for the Detection of Dirofilaria immitis Infection in Dogs.

In the last two decades, reports of canine heartworm (HW) infection have increased even in non-endemic areas, with a large variability in prevalence data due to the diagnostic strategy employed. This study evaluated the relative performance of two microtiter plate ELISA methods for the detection of HW antigen in determining the occurrence of Dirofilaria immitis in a dog population previously tested by the modified Knott’s test and SNAP 4Dx Plus test. The prevalence of this infection in the sheltered dog population (n = 363) from a high-risk area for HW infection was 44.4% according to the modified Knott’s test and 58.1% according to a point-of-care antigen ELISA. All serum samples were then evaluated by a microtiter plate ELISA test performed with and without immune complex dissociation (ICD). The prevalence increased from 56.5% to 79.6% following ICD, indicating a high proportion of samples with immune complexing. Comparing these results to that of the modified Knott’s test, the samples negative for microfilariae (mfs) and those positive only for D. repens mfs demonstrated the greatest increase in the proportion of positive results for D. immitis by ELISA following ICD. While the ICD method is not recommended for routine screening, it may be a valuable secondary strategy for identifying HW infections in dogs.

Comparative evaluation of field samples using 2 in-clinic assays for heartworm antigen detection in dogs

Dirofilaria immitis (heartworm) antigen testing is routinely performed in veterinary practices to detect canine heartworm infections. The purpose of this study was to evaluate the performance of two in-clinic assays to detect heartworm antigen on field samples from practices in heartworm endemic regions. Veterinary staff in 3 practices located in the Southern United States performed a side by side comparison of the SNAP® 4Dx® Plus Test (IDEXX) and the VETSCAN FLEX4® Test (Zoetis) on samples from canine patients presented for vector-borne disease screening. Assays were performed according to the manufacturer’s instructions. The remaining plasma sample was submitted for confirmatory testing using the PetChek® Heartworm Test (IDEXX) including immune complex dissociation (ICD) by heat treatment. A total of 232 samples were evaluated by the two in-clinic assays and PetChek Test. SNAP 4Dx Plus was significantly more sensitive for the detection of heartworm antigen in this study; sensitivity was 97.4 % for the SNAP 4Dx Plus test and 76.9 % for VETSCAN FLEX4 test (p < 0.01). The specificity of both tests was 99.5 %. This study reveals significant difference in detecting canine heartworm antigen in field samples.