Babesia canis canis and Babesia canis vogeli clinicopathological findings and DNA detection by means of PCR-RFLP in blood from Italian dogs suspected of tick-borne disease

Molecular Survey of Tick-Borne Haemoparasites of Dogs by Multiplex Polymerase Chain Reaction from Punjab, India

PURPOSE

Tick-transmitted parasites as Babesia gibsoni, Babesia vogeli, Ehrlichia canis, and Hepatozoon canis are major health concern for dogs. Owing to prevalence and infection severity, there is need of sensitive, specific, and affordable test for their simultaneous detection.

METHODS

Prevalence of B. gibsoni, B. vogeli, E. canis, and H. canis infections was assessed on 719 blood samples by microscopy and multiplex PCR assay targeting 18S rRNA (B. gibsoni & H. canis), ITS1 & 5.8S rRNA (B. vogeli) and VirB9 gene (E. canis). An internal control (canine-actin) was also included to increase the accuracy of assay and effect of associated risk factors with disease prevalence was also studied.

RESULTS

Microscopic prevalence of B. gibsoni, B. vogeli, E. canis and H. canis was 5.0%, 0.1%, 1.4% and 1.0%, respectively, whereas with multiplex PCR assay, the corresponding values were 8.9%, 1.1%, 2.6% and 5.1% besides concurrent infections of B. gibsoni & H. canis (0.4%), B. gibsoni & E. canis (0.4%), E. canis & H. canis (0.3%) and B. gibsoni & B. vogeli (0.1%). Analytical sensitivity of developed assay was 0.1pg (B. gibsoni & H. canis), 0.01pg (B. vogeli), and 1.0pg (E. canis). A ″fair″ (B. vogeli & H. canis) to ″substantial″ (B. gibsoni & E. canis) agreement between two tests was observed with data as statistically significant. Breed, sex and location were significantly associated with B. gibsoni infection.

CONCLUSION

The developed multiplex PCR assay offers a potential solution to detect these pathogens simultaneously, aiding in timely diagnosis and effective disease management in suspected dogs.

Molecular detection and characterization of Anaplasma marginale and Babesia canis vogeli infecting dogs in Luxor, Egypt

Tick-borne diseases in animals are increasing rapidly worldwide, but there is insufficient information about tick-borne diseases infecting dogs in southern Egypt. Thus, in the current study, we detected the presence of Anaplasma marginale (A. marginale) and Babesia canis vogeli (B. canis vogeli) in the blood of dogs. The results revealed that 4/100 (4%) were positive, and a higher infection rate was found in males (75%), than females (25%). The phylogenetic analysis for the major surface protein 4 (msp4) gene in this study was compared with amplicons separate from other reported isolates with alignment by identity 100% with cattle and camels from Egypt, and the phylogenetic analysis for the B. canis vogeli small subunit ribosomal RNA (SSU rRNA) gene in this study identified identity by 99.89% with dogs from Egypt. This report is considered the first report in southern Egypt about A. marginale in dogs based on the sequence analysis of the msp4 gene, providing new data for the classification and identification of A. marginale in dogs compared to A. marginale isolated from other animals in southern Egypt.

Island hitchhikers: pathogen agents of Madeira and Azores ticks

Ticks are blood-sucking arthropods that can transmit pathogens to their host. As insular ecosystems can enhance tick-host interactions, this study aimed to understand tick diversity, pathogen presence, and their respective associations in the Azores and Madeira archipelagos. Unfed or partially engorged ticks (n = 120) were collected from 58 cats and dogs in the Azores (n = 41 specimens) and Madeira (n = 79 specimens) from November 2018 to March 2019. Vector identification was based on morphology and molecular criteria. For pathogen sequencing, 18S gene fragment for Babesia/Hepatozoon and gltA for Rickettsia were performed. Sequence data was explored using BLAST and BLAST and phylogenetic inference tools. In the Azores, Ixodes hexagonus, I. ventalloi, and Rhipicephalus sanguineus (n = 6; 14.6%, n = 6; 14.6%, and n = 29; 70.7% respectively) were found and in Madeira I. ricinus and R. sanguineus (n = 78, 98.7%; and n = 1, 1.3%; respectively) were identified. Tick COI markers confirmed species highlighting confirmation of R. sanguineus s.s. and genotype A of I. ventalloi. In the Azores Islands, the detected Rickettsia massiliae was linked to R. sanguineus (dogs and cats) and I. hexagonus (dogs), and in Madeira Island, R. monacensis (dogs) and Hepatozoon silvestris (cats) were found associated with I. ricinus. Further, I. ventalloi presence in the Azores expands west its known range, and Hepatozoon silvestris in Madeira may suggest that I. ricinus could have a role as a potential vector. Finally, as R. massiliae and R. monacensis presence underlines public health risks, surveillance by health authorities is crucial as pathogen-tick interactions may drive disease spread, therefore monitoring remains pivotal for disease prevention.

Age, sex and breed effect on laboratory parameters in natural Babesia canis infection

We tested the hypothesis that age, breed, and sex are related to hematology, biochemistry, acute phase proteins (APPs), seroreactivity and level of parasitemia in dogs with an acute phase response (APR) due to Babesia canis infection. The study enrolled 61 privately owned dogs that naturally acquired B. canis infection. Groups were formed according to the age: young dogs less than one year, and adult dogs more than one year old. Moreover, the group of males was compared to females and purebred to mixed breed dogs. Seroreactivity was tested with immunofluorescence antibody test, level of parasitemia with real-time polymerase chain reaction (real-time PCR), hematology, and biochemistry with automatic analyzers, serum amyloid A with enzyme-linked immunosorbent assay, fibrinogen with heat precipitation and ceruloplasmin and paraoxonase-1 with manual spectrophotometric methods. For protein separation agarose gel electrophoresis was used. The main changes in the whole population of B. canis-infected dogs were fever, pancytopenia, and change in APPs level. One-third of young, and 96% of adult dogs were seropositive (P < 0.001). The level of parasitemia was higher in the young dogs (P < 0.001). Erythroid lineage parameters (P < 0.01), and leukocytes (P < 0.05) were lower in the young, when compared to the adult dogs. Young dogs had lower total globulins (P < 0.001), β- and γ-globulins (P < 0.001), and higher α-globulins (P = 0.022) than adult dogs. Young dogs had higher concentrations of phosphate (P = 0.003) and cholesterol (P < 0.001) and lower amylase (P = 0.014) and lipase activity (P = 0.020) than adult ones. Male dogs had lower neutrophil count than females (P = 0.035), and purebred dogs had more band neutrophils than mixed breed dogs (P = 0.004). In conclusion, dogs with natural Babesia canis infection at a young age have more severe anemia and APR including leukopenia than adults. Male and purebred dogs might also have more severe APR than females and mix-breeds, as they have more pronounced changes related to the myeloid lineage.

Completing the Puzzle: A Cluster of Hunting Dogs with Tick-Borne Illness from a Fishing Community in Tobago, West Indies

Eight hunting dogs were visited by a state veterinarian on the island of Tobago, Trinidad and Tobago, West Indies, as owners reported anorexia and paralysis in five of their dogs. The veterinarian observed a combination of clinical signs consistent with tick-borne illness, including fever, anorexia, anaemia, lethargy and paralysis. Blood and ticks were collected from each dog and submitted to a diagnostic laboratory for analysis. Microscopic analysis revealed a mixed infection of intracytoplasmic organisms consistent with Babesia spp. (erythrocyte) and Ehrlichia spp. (monocyte), respectively, from one dog, while a complete blood count indicated a regenerative anaemia (n = 1; 12.5%), non-regenerative anaemia (n = 4; 50%), neutrophilia (n = 3; 37.5%), lymphocytosis (n = 2; 25%), thrombocytopaenia (n = 3; 37.5%) and pancytopaenia (n = 1; 12.5%). DNA isolated from the eight blood samples and 20 ticks (16 Rhipicephalus sanguineus and 4 Amblyomma ovale) were subjected to conventional PCR and next-generation sequencing of the 16S rRNA and 18S rRNA gene for Anaplasma/Ehrlichia and Babesia/Theileria/Hepatozoon, respectively. The DNA of Ehrlichia spp., closely related to Ehrlichia canis, was detected in the blood of three dogs (37.5%), Anaplasma spp., closely related to Anaplasma marginale, in two (25%), Babesia vogeli in one dog (12.5%) and seven ticks (35%) and Hepatozoon canis and Anaplasma spp., in one tick (5%), respectively. These findings highlight the need to test both the vector and host for the presence of tick-borne pathogens when undertaking diagnostic investigations. Further studies are also warranted to elucidate the susceptibility of canids to Anaplasma marginale.

Tick-borne infections in wolves from an expanding population in Eastern Europe

In Central and Eastern Europe, wolf populations have been increasing over the last two decades, recolonizing areas from which the species had been previously exterminated. As wolves are still recovering after years of persecution by humans, recognizing pathogens infecting this species, including tick-borne infections, is crucial for its conservation. On the other hand the high mobility of wolves and their frequent contacts with humans, dogs, and other domestic species make them a potentially important zoonotic reservoir. In this paper, we used molecular methods to determine the prevalence of tick-borne pathogens in the following genera: Anaplasma, Babesia, Bartonella, Borrelia, and Rickettsia in 50 free-ranging wolves from Poland. We detected Babesia canis in the blood of nine individuals (prevalence 9/50=18 %). The obtained sequence showed the highest similarity to B. canis isolated from dogs and ticks, and all infected individuals originated from regions endemic to the ornate tick, Dermacentor reticulatus. Anaplasma phagocytophilum was found in tissue from one individual (1/50=2 %), and the sequence was assigned to the zoonotic ecotype I.

The Diverse Pathogenicity of Various Babesia Parasite Species That Infect Dogs

Babesia species infect a very wide range of mammal hosts across the globe, and zoonotic infections are of growing concern. Several species of the Babesia genus infect dogs, and some of these cause significant morbidity and mortality. The Apicomplexan parasite resides within the red cell and infections result in direct damage to the host through intra- and extravascular hemolysis. An exuberant inflammatory response by the host to some species of Babesia parasites also results in significant collateral damage to the host. Canine infections have been the subject of many studies as the well-being of these companion animals is increasingly threatened by the spread of tick vectors and an increasingly mobile dog population. There are currently no widely available and effective vaccines, and effective treatment can be challenging. Understanding disease pathogenesis underlies the development of new treatments. The varying pathogenicity of the various Babesia parasite species that infect dogs offers an opportunity to explore the molecular basis for the wide range of diseases caused by infection with this parasite genus. In this review, we focus on what has been reported about the clinical presentation of Babesia-infected dogs in an attempt to compare the severity of disease caused by different Babesia species.

Molecular detection of Babesia spp. in dogs in Germany (2007-2020) and identification of potential risk factors for infection

BACKGROUND

In Europe, canine babesiosis is most frequently caused by Babesia canis and Babesia vogeli, and occasionally by Babesia gibsoni.. In Germany, B. canis is recognized as endemic. The aims of this study were to assess how often Babesia spp. infections were diagnosed in a commercial laboratory in samples from dogs from Germany, and to evaluate potential risk factors for infection.

METHODS

The database of the LABOKLIN laboratory was screened for Babesia spp.-positive polymerase chain reaction (PCR) tests for dogs for the period January 2007-December 2020. Sequencing was performed for positive tests from 2018 and 2019. Binary logistic regression analysis was performed to determine the effects of sex, season, and year of testing. Questionnaires were sent to the submitting veterinarians to obtain information on travel abroad, tick infestation, and ectoparasite prophylaxis of the respective dogs. Fisher's exact test was used to calculate statistical significance and P < 0.05 was considered statistically significant.

RESULTS

In total, 659 out of 20,914 dogs (3.2%) tested positive for Babesia spp. by PCR. Of 172 sequenced samples, B. canis was identified in 156, B. vogeli in nine, B. gibsoni in five, and B. vulpes in two. Season had a statistically significant impact on test results when summer/winter (1.6% tested positive) was compared to spring/autumn (4.7%), with peaks in April (5.2%) and October (7.4%) [P < 0.001, odds ratio (OR) = 3.16]. Sex (male 3.5%, female 2.8%; P = 0.012, OR = 1.49) and age (< 7 years old 4.0%, ≥ 7 years old 2.3%; P < 0.001, OR = 1.76) of the tested dogs also had a statistically significant effect. A statistically significant impact was demonstrated for observed tick attachment (P < 0.001, OR = 7.62) and lack of ectoparasite prophylaxis (P = 0.001, OR = 3.03). The frequency of positive Babesia spp. tests did not significantly differ between the 659 dogs that had never left Germany and the 1506 dogs with known stays abroad (P = 0.088).

CONCLUSIONS

The possibility of canine infection with B. canis needs to be especially taken into consideration in spring and autumn in Germany as the activity of the tick Dermacentor reticulatus, a potential vector for canine babesiosis, is highest in these seasons. Travel and importation of dogs are considered major factors associated with canine babesiosis in Germany. However, autochthonous Babesia spp. infections also occur in a considerable number of dogs in Germany.

Evaluation of recombinant Babesia gibsoni thrombospondin-related adhesive protein (BgTRAP) for the sero-diagnosis of canine babesiosis

Canine babesiosis, caused by Babesia gibsoni is one of the most significant tick-borne illnesses across the world. Light microscopy as well as polymerase chain reaction may fail in the diagnosis of disease when the level of parasitaemia is very low during subclinical and chronic cases. The serological techniques using a recombinant protein will be useful for the accurate and sensitive surveillance of the disease, especially in chronic cases. The present study describes the evaluation of recombinant N-terminal B. gibsoni Thrombospondin-related adhesive protein (BgTRAP) based indirect ELISA for the sero-diagnosis of B. gibsoni infection in dogs. A partial N-terminal BgTRAP gene (870 bp) of B. gibsoni, was expressed in Escherichia coli using a pET32a (+) vector. The recombinant BgTRAP based indirect ELISA was compared with the PCR targeting the same gene. A sensitivity and a specificity of 84% and 73.33% were observed in the indirect ELISA. The accuracy, positive predictive value and negative predictive value were 78.18%, 72.30%, 84.60% respectively. The rBgTRAP antigen did not show any cross-reactivity with sera from dogs infected with common helminth parasites viz. Ancylostoma caninum, Dirofilaria immitis, D. repens, Spirometra spp., Toxocara canis and haemoparasites like Trypanosoma evansi, Babesia vogeli, Hepatozoon canis and Ehrlichia canis.

Canine Babesiosis Caused by Large Babesia Species: Global Prevalence and Risk Factors-A Review

Canine babesiosis is a disease caused by protozoan pathogens belonging to the genus Babesia. Four species of large Babesia cause canine babesiosis (B. canis, B. rossi, B. vogeli, and the informally named B. coco). Although canine babesiosis has a worldwide distribution, different species occur in specific regions: B. rossi in sub-Saharan Africa, B. canis in Europe and Asia, and B. coco in the Eastern Atlantic United States, while B. vogeli occurs in Africa, southern parts of Europe and Asia, northern Australia, southern regions of North America, and in South America. B. vogeli is the most prevalent large Babesia species globally. This results from its wide range of monotropic vector species, the mild or subclinical nature of infections, and likely the longest evolutionary association with dogs. The most important risk factors for infection by large Babesia spp. include living in rural areas, kennels or animal shelters, or regions endemic for the infection, the season of the year (which is associated with increased tick activity), infestation with ticks, and lack of treatment with acaricides.

Detection and Molecular Characterization of Canine Babesiosis Causative Agent Babesia canis in Naturally Infected Dogs in the Dobrogea Area (Southeastern Romania)

Canine babesiosis is an emerging tick-borne disease of major veterinary concern in Europe. Its prevalence has increased in the last two decades and is spreading rapidly toward the north. The aim of this study was to investigate the genetic diversity of Babesia spp. strains isolated from naturally infected dogs in a tick-endemic area (Dobrogea) in southeastern Romania. For this purpose, a total of twenty-three samples from dogs diagnosed with various clinical forms of babesiosis, evaluated by means of clinical history, physical examination, and hematological tests, were subjected to a molecular investigation using PCR, sequencing analysis, and genetic characterization. A microscopic examination of thin Diff-quick-stained blood smears revealed large intra-erythrocytic Babesia piroplasms in all dogs. The PCR and sequencing analysis results indicated the presence of Babesia canis in 22 dogs (95.7%) and Babesia vogeli in 1 dog (4.3%). Among the B. canis isolates, two genotypes were distinguished based on two nucleotide substitutions (GA→AG) observed in the 18S rRNA gene sequences (at positions 609 and 610), with the AG genotype predominating (54.5% of samples), while the GA variant was identified in 9.1% of samples. In the remaining isolates (36.4%), both variants were identified. The B. vogeli-positive dog also tested positive for antibodies against Ehrlichia canis and displayed severe disease. This study reports, for the first time, the presence of genetically heterogenic B. canis strains in dogs with clinical babesiosis in Romania. These findings provide a basis for future studies on the relationship between the genetic structure of the causative agents of canine babesiosis in Romania and the course of the disease.

Clinical presentation, diagnostic investigations, treatment protocols and outcomes of dogs diagnosed with tick-borne diseases living in the United Kingdom: 76 cases (2005-2019)

OBJECTIVES

To report the presence of tick-borne diseases in dogs living in the United Kingdom.

MATERIALS AND METHODS

Dogs with a final diagnosis of tick-borne diseases made between January 2005 and August 2019 at seven referral institutions in the United Kingdom were included in the study.

RESULTS

Seventy-six dogs were included: 25 were diagnosed with ehrlichiosis, 23 with babesiosis, eight with Lyme borreliosis and six with anaplasmosis. Fourteen dogs had co-infections with two or three pathogens. Except for those dogs with anaplasmosis and Lyme borreliosis, most dogs with tick-borne diseases had a history of travel to or from endemic countries. However, three dogs with ehrlichiosis, and one dog each infected with Babesia canis and Babesia vulpes did not have any history of travel. A variety of non-specific clinical signs and laboratory abnormalities were reported. Targeted treatment was successful at achieving clinical remission in 64 (84%) dogs.

CLINICAL SIGNIFICANCE

Even in non-endemic areas, veterinary surgeons should consider tick-borne diseases in dogs with compatible clinical presentation and laboratory findings and especially where there is a history of travel. As autochthonous transmission of tick-borne-pathogens does occur, an absence of travel should not rule out tick-borne diseases. Specific diagnostic testing is required to confirm infection, and this enables prompt targeted treatment and often a positive outcome.

Correlation between Babesia Species Affecting Dogs in Taiwan and the Local Distribution of the Vector Ticks

The objective of our study was to survey Babesia infection rates by PCR and tick species on stray dogs to correlate the distribution of Babesia with the distribution of ticks infesting dogs in Taiwan. Three hundred eighty-eight blood samples and 3037 ticks were collected from 388 roaming, and free-ranging owned dogs at residential sites in Taiwan between January 2015 and December 2017. The prevalence of B. gibsoni and B. vogeli was 15.7% (61/388) and 9.5% (37/388), respectively. Most positive B. gibsoni dogs were found in the northern part of the country 56/61 (91.8%), whereas a few were found in the middle 5/61 (8.2%). Babesia vogeli infection rates were 10%, 3.6%, and 18.2% in the northern, central, and southern regions, respectively. Five species of ticks were found: Rhipicephalus sanguineus (throughout Taiwan), Rhipicephalus haemaphysaloides (in the north), Haemaphysalis hystricis (in the north and middle of Taiwan), and Amblyomma testidunarium and Ixodes ovatus (both in the north). None of the dogs in the south were infected with B gibsoni, which correlated with the absence of H. hystricis, a tick recently identified as the local vector for B gibsoni. Babesia vogeli was more equally distributed, coinciding with R. sanguineus, a tick that is present throughout Taiwan. Anaemia was detected in 86.9% of infected dogs; among these dogs, approximately 19.7% showed severe anaemia (HCT < 20). These findings provide useful advice for owners regarding outdoor activities with their dogs and local veterinarians with a regional differential diagnosis of babesiosis in Taiwan.

Prevalence and geographic distribution of Babesia conradae and detection of Babesia vogeli in free-ranging California coyotes (Canis latrans)

Babesia species are intraerythrocytic piroplasms that can result in disease characterized by hemolytic anemia and thrombocytopenia. Of the 5 species that are known to infect canids in the United States, Babesia conradae is most frequently diagnosed in California, and Babesia vogeli is prevalent in the US. Despite the recent re-emergence of B. conradae, the mechanism of transmission is not known. Coyotes (Canis latrans) have been a proposed reservoir of disease, and previous work has shown that dogs with known aggressive interactions with coyotes are at greater risk for infection. This study aimed to determine the prevalence of B. conradae in wild coyote populations in California to assess the viability of coyotes as a potential source of infection for domestic dogs. Four hundred and sixty-one splenic samples were obtained during post-mortem examination of coyote carcasses from Southern California, Fresno, and Hopland. Demographic data including age, sex, cause of death, and urbanity were collected for each coyote. DNA was extracted from samples and amplified using real-time PCR with primers specific for the B. conradae ITS-2 gene. The 18S gene was amplified and sequenced using conventional PCR primers specific to the Babesia genus from any coyotes positive for B. conradae. In total, 22 coyotes tested positive for B. conradae in Fresno (n = 15), Orange (n = 4), San Bernardino (n = 1), and Los Angeles counties (n = 1) with an overall prevalence of 4.8%. Coyotes from Fresno (P<.01) and rural coyotes (P<.01) were significantly more likely to be infected with B. conradae. Ten of 14 samples sequenced were 99-100% homologous to B. conradae, and 4 samples were 100% homologous with B. vogeli DNA indicating co-infection with both pathogens. This study demonstrates that coyotes can become infected and harbor B. conradae and B. vogeli and should be investigated as a possible source of infection in domestic dogs.

Sensitive and rapid detection of Babesia species in dogs by recombinase polymerase amplification with lateral flow dipstick (RPA-LFD)

Canine babesiosis is a tick-borne disease caused by Babesia spp., which infects and destroys healthy erythrocytes, leading to mortality and morbidity in dogs. The diagnosis of babesiosis is tedious and time-consuming, especially in latent and chronic infections. Here, a recombinase polymerase amplification combined with a lateral flow dipstick (RPA-LFD) assay was developed for rapid and accurate detection of Babesia spp. in canine blood specimens based on the 18S rRNA region. The RPA-LFD assay using rpaBab264 gave specificity to Babesia spp. in dogs (B. vogeli and B. gibsoni) without cross-amplification to other parasites (apicomplexans and non-apicomplexans), with detection limit of at least 22.5 copies/μl (0.1 fg/µl) at 40 °C for at least 10 min. The whole process of DNA amplification by RPA and readout by LFD did not exceed 30 min. To determine the performance of the RPA-LFD assay, a total of 30 clinical samples was examined and compared with conventional PCR (cPCR) and multiplex HRM (mHRM). Eight dogs (26.67%) were detected as positive by RPA-LFD, while seven and six were found positive by cPCR and mHRM, respectively. RPA-LFD and cPCR showed high agreement with Babesia spp. detection with kappa > 0.9. We confirmed that the dogs were infected by B. vogeli from sequences of positive PCR results. Our findings suggested that RPA-LFD using the rpaBab264 assay offered a rapid, accurate, cost-effective and simple method for Babesia spp. detection that is feasibly applicable to be rapid kit at a pet hospital or point-of-care testing.

Molecular Prevalence of Selected Tick-Borne Pathogens in Dermacentor reticulatus Collected in a Natural Park in Italy

Dermacentor reticulatus is one of the most important vectors of tick-borne pathogens (TBPs) in Europe causing diseases in animals and humans. A longitudinal study was planned, aimed to detect the molecular prevalence of tick-borne pathogens, i.e., Babesia spp. and the spotted fever group Rickettsiae, and its seasonal variation in D. reticulatus questing ticks to define the temporal infection risk. Ticks were collected monthly over a period of 15 months in a peri-urban park in Lombardy, Italy. DNA extraction and molecular analyses were performed. Statistical analysis was carried out. Out of 488, 53 (P = 10.9%) adult questing ticks were positive for Babesia DNA. A higher prevalence was revealed in male (32/241, P = 13.3%) than in female (21/247, P = 8.5%) ticks. Positive ticks were mostly collected in winter months (P = 13.3%) compared to early (P = 7.9) and late (P = 12.8) spring months. A similar percentage of positive ticks was evidenced in transects 1 and 3 (5.8% and 6.5%, respectively); instead, a significant higher prevalence was recorded in transect 2 (P = 16.0%). Obtained sequences confirmed a homology of 100% with B. canis sequences deposited in GenBank. No ticks tested positive for Rickettsia spp. DNA (0/488, P = 0%). The conspicuous circulation of B. canis infection in D. reticulatus adult questing ticks confirms their role in the epidemiology of canine babesiosis and requires preventive measures for dogs in this recreational area. Even if no tick was positive for the spotted fever group Rickettsia, its capacity as a vector of zoonotic pathogens should not be neglected.

Vector-borne pathogens of zoonotic concern in hunting dogs of southern Italy

Dogs are commonly exposed to vector-borne pathogens (VBPs), yet few data are available on hunting dogs, which are often at high risk of infection due to their involvement in field activities. To investigate the occurrence of VBPs and evaluate the relative performance of different diagnostic tools, blood and serum samples were collected from hunting dogs (n = 1,433) in rural areas of southern Italy. All samples were tested by Knott's technique for filarioids, serologically (SNAP® 4Dx® Plus) for Anaplasma spp., Borrelia burgdorferi sensu lato, Dirofilaria immitis and Ehrlichia spp. and molecularly (qPCR) for all except B. burgdorferi of the above pathogens plus Babesia spp. and Leishmania infantum. Logistic regression was run to evaluate the statistical associations between the risk of VBP infection and independent variables (such as geographic area of provenience, age class and sex) and K-Cohen formula for assessing the concordance among diagnostic tests. Overall, out of 321 dogs (22.4%) positive to at least one VBP, 28 (1.9%) were infected by filarial species at the Knott's technique. In particular, Acanthocheilonema reconditum was the most prevalent (1.6%), followed by D. immitis (0.2%) and Dirofilaria repens (0.1%). One hundred forty (9.8%) and 231 (16.1%) dogs scored positive to VBPs by serological and molecular methods, respectively. The most prevalent pathogens detected were Ehrlichia spp. (7.3%) with SNAP® 4Dx® Plus, and A. reconditum (7.7%) by qPCR. Statistics revealed a significant association (p < 0.001) between A. reconditum infestation and both Ehrlichia spp. seropositivity and geographical origin of dogs. An agreement of 99.9%, 94.0% and 95.7% for Knott - SNAP® 4Dx® Plus, Knott - qPCR and SNAP® 4Dx® Plus - qPCR for D. immitis was found, respectively. Data demonstrate a high prevalence of VBPs in hunting dogs, indicating that this group of animals is largely exposed to several arthropod vector species and suggesting the transmission risk of pathogens to humans in rural areas of southern Italy. A multi-diagnostic approach and a deeper cooperation among healthcare and stakeholders are required to prevent VBP infections to animals and humans.

Distribution of Tick-Borne Pathogens in Domestic Animals and Their Ticks in the Countries of the Mediterranean Basin between 2000 and 2021: A Systematic Review

Tick-borne pathogens (TBPs) include a wide range of bacteria, parasites and viruses that cause a large spectrum of animal, human and zoonotic tick-borne diseases (TBDs). The object of this review was to establish an inventory and an analysis of TBPs found in domestic animals in the countries of the Mediterranean Basin. This geographic area occupies a central position between several continents and is an area of movement for animals, humans and pathogens of interest and their vectors, which is important in terms of animal and human health. In this systematic review, we included a total of 271 publications produced between 2000–2021 concerning TBPs in domestic animals. Among this literature, we found a total of 90 pathogen species (known as TBPs) reported in the 20 countries of the area; these were detected in tick species from domestic animals and were also directly detected in domestic animals. In all, 31 tick species were recorded and 12 domestic animal species, the latter comprising nine livestock and three pet species. More than 50% of the publications were from Western Europe. Island data were extracted and assessed, as islands of the Mediterranean Basin were represented in 16% of the publications and 77.8% of the TBPs reported. Our results show the importance of islands in the monitoring of TBPs, despite the low percentage of publications.

Van İlindeki Sokak Köpeklerinde Babesia Türlerinin Polimeraz Zincir Reaksiyonu Yöntemi İle Araştırılması

Amaç: Köpek babesiosisi Babesia spp.’ nin neden olduğu hemolitik anemi, splenomegali, trombositopeni ve ateşe neden olabilen kene kaynaklı bir protozoal hastalıktır. Türkiye’de yapılan moleküler çalışmalar soncunda B. canis, B. gibsoni, B. vogeli, B. rossi ve B. vulpes türlerinin varlığı ortaya konulmuştur. Yapılan literatür taramalarına göre Van ilinde yaşayan köpeklerde Babesia türlerini ortaya koyan herhangi bir çalışma bulunmamaktadır. Bu çalışma, Van ilindeki köpeklerde babesiosisin varlığı ve yaygınlığının Polimeraz Zincir Reaksiyonu (PZR) tekniği ile araştırılması amacıyla yapılmıştır. Yöntem: Rastgele seçilen toplam 100 asemptomatik köpeğin vena cephalica antebrachii’lerinden EDTA’lı tüplere kan örnekleri alınmıştır. Alınan örneklerden elde edilen DNA’lar, Babesia spp.’ nin varlığı yönünden 18S ribozomal RNA geninin amplifiye edildiği PZR yöntemi ile araştırılmıştır. Bulgular: Muayene edilen 100 köpeğin PZR sonuçlarına göre hiçbirinde Babesia spp. DNA’sına rastlanmamıştır. Sonuç: Bu çalışma ile Van yöresi sokak köpeklerinde ilk kez Babesia spp. türleri moleküler olarak araştırılmıştır.

Clinical characteristics of naturally Babesia gibsoni infected dogs: A study of 60 dogs

Babesia gibsoni is increasingly recognized globally as a cause of canine tick-borne anemic disease; however, only a few clinical reports of naturally acquired infection are available. In this systematic study of dogs presenting with B. gibsoni infection, clinical and laboratory data were collected for dogs with PCR-confirmed B. gibsoni infection admitted to the National Taiwan University Veterinary Teaching Hospital (NTUVH) from January 2014 through December 2015. Of the 60 dogs recruited, 20 (33.3%) had concurrent disease and 40 (66.7%) had only B. gibsoni infection. The severity of anemia in B. gibsoni infected dogs with concurrent or without concurrent infection was not significantly different. The most commonly observed hematological abnormalities were anemia (49/60, 81.7%) and thrombocytopenia (37/60, 61.7%). Of 49 dogs, 24 (49%) had severe to very severe anemia (PCV < 20%). The main biochemical abnormalities included hyperglobulinemia (28/53, 52.8%), hyperbilirubinemia (10/28, 35.7%) and elevated hepatic enzyme activity (7/48, 14.6%). In addition, 2 of the 60 the client-owned dogs and 5 of the 33 B. gibsoni-positive stray dogs were detected as having a naturally atovaquone-resistant strain, using the SimpleProbe® assay. The study results provide a useful clinical presentation of B. gibsoni infection and raise the issue of the naturally atovaquone-resistant strain currently existing in Taiwan.

Identification of parameters and formulation of a statistical and machine learning model to identify Babesia canis infections in dogs using available ADVIA hematology analyzer data

BACKGROUND

Canine babesiosis is an important tick-borne disease in endemic regions. One of the relevant subspecies in Europe is Babesia canis, and it can cause severe clinical signs such as hemolytic anemia. Apart from acute clinical symptoms dogs can also have a more chronic disease development or be asymptomatic carriers. Our objective was to identify readily available ADVIA hematology analyzer parameters suggestive of B. canis parasitemia in dogs and to formulate a predictive model.

METHODS

A historical dataset of complete blood count data from an ADVIA hematology system with blood smear or PCR confirmed parasitemia cases was used to obtain a model by conventional statistics (CS) methods and machine learning (ML) using logistical regression and tree methods.

RESULTS

Both methods identified that important parameters were platelet count, mean platelet volume and percentage large unstained cells. We were able to formulate a CS model and ML model to screen for Babesia parasitemia in dogs with a sensitivity of 84.6% (CS) and 100% (ML), a specificity of 97.7% (CS) and 95.7% (ML) and a positive likelihood ratio (LR+) of 36.78 (CS) and 23.2 (ML).

CONCLUSIONS

This study introduces two methods of screening for B. canis parasitemia on readily available data from ADVIA hematology systems. The algorithms can easily be introduced in laboratories that use these analyzers. When the algorithm marks a sample as 'suggestive' for Babesia parasitemia, the sample is approximately 37 times more likely to show Babesia merozoites on blood smear analysis.

Molecular discrimination and genetic diversity of three common tick-borne pathogens in dogs in Thailand

There was little information regarding the occurrence of canine vector-borne disease (CVBDs) in shelter dogs in Thailand. This work is the first report regarding a molecular method used to determine the occurrence and genetic diversity of three canine tick-borne pathogens (TBPs) (Hepatozoon canis, Anaplasma platys and Ehrlichia canis) in blood samples from 275 shelter dogs in the north and central areas of Thailand. The PCR results based on the 18S rRNA and 16S rRNA genes showed that 71 (25.82%) dogs were positive for at least a TBP. The overall occurrence rates of H. canis, A. platys and E. canis infections were 1.81, 16.36 and 7.64%, respectively. For the phylogenetic analysis, A. platys 16S rRNA gene was genetically diverse, while H. canis 18S rRNA and E. canis 16S rRNA genes were conserved. The haplotype diversity exhibited 12 and 2 haplotypes as well as 78 and 178 polymorphic sites of A. platys and E. canis 16S rRNA genes, respectively. Our findings could be used to improve the understanding of phylogeny and genetic diversity of TBP rRNA genes and used to ameliorate the diagnosis and control programmes for the diseases in Thailand.

Occurrence of Babesia Species and Co-Infection with Hepatozoon canis in Symptomatic Dogs and in Their Ticks in Eastern Romania

Although the distribution of Babesia spp. and Hepatozoon canis is well known in Romania, there is still a marked lack of information in many places of the country. This study aimed to investigate the occurrence of these haemoparasites in symptomatic dogs and in their ticks in Iasi, eastern Romania. Ninety owned dogs were subjected to clinical examination at the Faculty of Veterinary Medicine of Iasi and all detectable ticks (58 ticks from 15 dogs) were collected. Additionally, 124 ticks collected from the coat of other dogs (no. = 23) were included. Three Babesia species were found in dogs: Babesia canis (94.4%), Babesia vogeli (3.3%), and Babesia rossi (2.2%). All the dogs resulted negative for H. canis. The ticks were identified as follows: Ixodes ricinus (64%), Dermacentor reticulatus (33%), and Rhipicephalus sanguineus group (3%). B. canis (Minimum Infection Rate; MIR = 81%), B. vogeli (MIR = 3%), and Babesia microti-like piroplasm (MIR = 1%) were found in ticks. Moreover, 15 ticks were positive for H. canis, 6 were co-infected with B. canis, and 1 with B. microti-like piroplasm. This is the first molecular identification of B. rossi in two symptomatic dogs from Romania, although further studies are needed to investigate the vector competence of other ticks from Europe.

Simultaneous Exposure to Angiostrongylus vasorum and Vector-Borne Pathogens in Dogs from Italy

Several drivers have recently fostered the expansion of Angiostrongylus vasorum throughout Europe, where Vector-Borne Pathogens (VBPs) are also spreading. However, the level of simultaneous risk of infection is still unknown in canine populations. This study evaluated the simultaneous exposure to A. vasorum and major canine VBPs in dogs of Italy. Sera of 294 dogs were subjected to two ELISAs, detecting A. vasorum circulating antigens and antibodies against the parasite, and to the following assays: (i) SNAP® 4DX (IDEXX Laboratories Inc.) detecting Dirofilaria immitis antigens, and antibodies vs. Borrelia burgdorferi, Anaplasma spp. and Ehrlichia spp. and (ii) IFAT for the detection of antibodies vs. Leishmania infantum, Babesia canis and Rickettsia conorii. Twenty-two (7.5%, CI: 4.8-11.1%) and six (2%, CI: 0.7-4.4%) dogs scored positive for circulating A. vasorum antibodies and antigens, respectively. Seventeen dogs (5.8%, CI: 3.4-9.1%) were positive for A. vasorum antibodies + at least one VBP, three (1%, CI: 0.2-3%) for A. vasorum antigen + at least one VBP, while one dog (0.3%, CI: 0.01-1.88%) was positive for A. vasorum antigen + A. vasorum antibodies + B. canis antibodies. These results show that dogs living in different regions of Italy are at risk of simultaneous infections with both A. vasorum and VBPs. Despite the same scenario being likely in other countries of Europe, the current knowledge is scant. Therefore, further studies are warranted to amplify current epizootiological information and to understand whether control programs should be improved.

Seroprevalence and prevalence of Babesia vogeli in clinically healthy dogs and their ticks in Costa Rica

Canine babesiosis is a disease caused by a parasite of the genus Babesia which destroys red blood cells. Previous studies have shown the presence of Babesia vogeli in rural areas in Costa Rica using molecular techniques. The objective of the present study was to determine the seroprevalence and prevalence of B. vogeli in clinically healthy dogs and their ticks at the national level, both within and outside the Central Valley. Blood samples and ticks from 482 dogs were collected between June 2011 and May 2014, and analyzed by immunofluorescence assay (IFA) and real-time polymerase chain reaction (qPCR); two protocols of endpoint PCR and sequencing were used to confirm qPCR-positive samples. Seroprevalence of canine babesiosis of 5.3% (24/453) was determined at the national level, specifically 2.0% (5/253) within and 9.5% (19/200) outside the Central Valley, respectively. Real-time PCR determined a global prevalence of B. vogeli of 31.3% (125/400): 21.4% (47/220) within the Central Valley and 43.3% (78/180) outside the Central Valley. The endpoint PCR amplified only 10 of the 125 blood samples identified as positive in qPCR. One sample amplified by endpoint PCR was sequenced and identified as B. vogeli. Twelve canines were identified with past infections, seven canines with active infection, and 111 canines with early infection. Two species of ticks were found with B. vogeli: Rhipicephalus sanguineus sensu lato (n = 40) and Amblyomma ovale (n = 1). The prevalence of canine babesiosis at the national level, both within and outside the Central Valley, is reported here for the first time, determining the presence of the piroplasmid throughout the country, with a higher circulation of the agent outside the Central Valley. Only one species, B. vogeli, was detected in the blood of dogs and their ticks. Therefore, veterinarians should consider using qPCR to determine the presence of the parasite in blood donors and before starting treatment of vector-borne disease in dogs.

Babesia gibsoni infection in Italy: a cross sectional study of 607 blood samples belonging to dogs that needed a molecular analysis investigation (2016-2019)

Babesia gibsoni (B. gibsoni) infection was sporadically described in Europe. In Italy, in particular, it was detected by PCR analysis only in one dog with unclear source of infection, while it has never been found in molecular studies involving more subjects. The aim of this retrospective, cross-sectional study was to determine the presence and the proportion of B. gibsoni infected dogs in a convenient Italian canine population. Babesia spp PCR analysis reports of canine blood samples collected from January 2016 to December 2019 were selected from the San Marco veterinary laboratory database and evaluated. Piroplasms PCR analysis was performed on 18S rRNA gene and positive samples were sequenced. Available data about signalment, living area and season of diagnosis were evaluated and statistically analyzed. The studied canine population had a median age of 62 months (interquartile range, IQR: 72.5) and was composed of male/female purebred and mixed breed dogs. Through sequencing, B. canis (26/40, 65%), B. vogeli (7/40, 17.5%), B. gibsoni (6/40, 15%) and B. vulpes (1/40, 2.5%) infections were reported. The proportion of B. gibsoni infected dogs in the described population was of 0.99%. The infection resulted more likely in male (6/6, 100%), purebred (5/6, 83.3%) dogs with median age of 40.5 months (IQR:32.3). In one case, the clinical signs and parasitemia appeared after a dogfight with a cohabitant infected dog. No other plausible sources of infection were detected. Likely, this could be considered the first autochthonous B. gibsoni infection case documented in Italy. Our results underline the need of considering B. gibsoni not only an exotic, random and rare cause of disease for dogs in Italy, but a possible emerging pathogen to take into account during diagnostic and epidemiological investigations, in symptomatic as well as in asymptomatic patients.

Prevalence and distribution of pathogen infection and permethrin resistance in tropical and temperate populations of Rhipicephalus sanguineus s.l. collected worldwide

The brown dog tick, Rhipicephalus sanguineus sensu lato (s.l.) Latreille (Acari: Ixodidae), is a peridomestic, cosmopolitan parasite of dogs known to vector numerous pathogens of veterinary and medical importance. Recent phylogenetic analyses separate this tick into temperate and tropical lineages. Populations of Rh. sanguineus s.l. have been reported to exhibit sodium channel target site insensitivity to permethrin and etofenprox, which is likely due to the prolonged use of pyrethroids against many pests in and around the home. In this study, populations collected in the Caribbean, Africa, Asia, Europe and North America, were tested to identify the distribution of a known resistance mechanism, pathogen-vector interactions and phylogeny in relation to latitude. Using molecular assays, populations from 29 distinct locations were simultaneously geographically typed and screened for bacterial infection by Rickettsia, Ehrlichia, Babesia and Hepatozoon species, and for the presence of a sodium channel single nucleotide polymorphism known to confer permethrin resistance. Implications of these results on Rh. sanguineus s.l. management in association with geographical distribution will be discussed.

Exposure to Major Vector-Borne Diseases in Dogs Subjected to Different Preventative Regimens in Endemic Areas of Italy

Vector-borne diseases (VBDs) are globally widespread arthropod-transmitted diseases with a significant impact on animal and human health. Many drivers have recently spurred the geographic spread of VBDs in dogs. This study has evaluated the exposure to most important VBDs in dogs under different preventative treatments in different regions of Italy, i.e., Veneto, Friuli Venezia-Giulia, Umbria, Giglio Island (Tuscany), Abruzzo and Latium. Serological analyses were performed to detect antibodies against Leishmania infantum, Babesia canis, Anaplasma phagocytophilum/Anaplasma platys, Ehrlichia canis/Ehrlichia ewingii, Borrelia burgdorferi, Rickettsia conorii and the circulating antigen of Dirofilaria immitis. Dogs were categorized according to the treatment schedule usually received, and the association between seropositivity and possible risk factors was statistically evaluated. Overall, 124/242 (51.2%) dogs tested positive for at least one pathogen, while 34 (14.0%) were exposed to two or more pathogens. The most detected seropositivity was against R. conorii, followed by Anaplasma spp., L. infantum, B. canis, and the other pathogens under study. Significant statistical associations were found according to geographical provenance, history of tick infestation, lifestyle and inadequate prophylactic treatments. Random/irregular treatments have been identified as a clear risk factor. These results show that adequate prophylactic treatment protocols are overlooked by dog owners, despite the availability of several effective products, with possible implications in veterinary medicine and on public health.

Prevalence, genetic, and biochemical evaluation of immune response of police dogs infected with Babesia vogeli

Background and Aim:

Babesia species are tick-borne protozoan parasites of apicomplexan type which infect the erythrocytes of dogs it ranges from subclinical to severe cases, depending on different factors such as immune status, age, and presence of other co-infections with the Babesia species. Hence, this study aimed to identify the protozoan parasites infecting police dogs of different breeds, ages, and both sexes in Egypt. Concerning molecular detection of Babesia vogeli using conventional polymerase chain reaction sequencing and phylogenetic analysis, followed by the assessment of immunological and biochemical status of infected dogs.

Materials and Methods:

The blood of 242 police K9 dogs was collected. The age, breed, sex, and health status with clinical signs of dogs were recorded. Hematological, biochemical, and oxidative stress analyses of the blood were performed together with gene expression analysis using two genes (gamma interferon [IFN-γ] and tumor necrosis factor-alpha [TNF-α]). The identification of the causative agent was performed using molecular analysis of the 18S ribosomal RNA (rRNA). The 18S rRNA region of canine Babesia spp. was successfully amplified, and sequencing data were deposited in GenBank (accession number: MT565474.1), which resembled those of B. vogeli.

Results:

The results of blood samples screening revealed that of the 242 blood samples, 62 were positive for B. vogeli infection. The infection rate in male dogs was higher than that in female dogs. The police dogs were classified into the following three groups of dogs: (1^st group) healthy, (2^nd infected with B. vogeli, and mixed infection of B. vogeli and Ehrlichia canis). The oxidative stress biomarkers levels in B. vogeli infected dogs were greater than that of healthy dogs. Likewise, IFN-γ and TNF-α level in B. vogeli infected dogs were elevated in infected dogs.

Conclusion:

Our findings demonstrated that B. vogeli had completely adverse effects on the health condition of the police dogs that may lead to death in some dogs.

Development and application of multiplex PCR assay for the simultaneous detection of Babesia vogeli, Ehrlichia canis and Hepatozoon canis in dogs

A multiplex PCR assay was standardized and evaluated to simultaneously detect the DNA of Babesia vogeli, Ehrlichia canis and Hepatozoon canis in dogs of selected districts of Punjab state, India. Amplicons of 602 bp, 380 bp and 306 bp corresponding to B. vogeli (18S rRNA gene), E. canis (VirB9 gene), and H. canis (18S rRNA gene) were obtained, without any non-specific amplification. The results of multiplex PCR assay were further compared with the corresponding singleplex PCR assay. The diagnostic sensitivity and specificity of multiplex PCR assay with respect to singleplex PCR assay in the detection of B. vogeli, E. canis and H. canis varied from 50% to 100% and 92.08% to 98.79%, respectively revealing "moderate" to "very good" agreement by kappa value statistics. Blood samples from 322 dogs collected from selected districts of Punjab state, India, when screened by microscopy revealed the prevalence of B. vogeli, E. canis and H. canis as 0.31%, 0.93% and 1.86%, respectively whereas with multiplex PCR assay the values were 0.93%, 10.24% and 4.65%, respectively, with concurrent infection of E. canis & H. canis (1.86%) and B. vogeli & E. canis (0.31%). The diagnostic sensitivity and specificity of multiplex PCR assay with respect to microscopy in the detection of B. vogeli, E. canis and H. canis varied from 69.15% to 100% and 85.11% to 92.33%, respectively revealing "fair" agreement by kappa value statistics and the data was statistically significant. The analytical sensitivity of multiplex PCR assay in the detection of B. vogeli, E. canis and H. canis was 100 pg, 10 pg and 0.1 pg, respectively, whereas the values for the singleplex counterpart were 0.1 pg, 0.01 pg and 0.01 pg. Furthermore, various risk factors viz. age, breed, sex, season and districts were non-significantly associated with the prevalence of these haemoparasites except for E. canis that revealed a significant association with districts by multiplex PCR assay. Therefore the multiplex PCR assay developed may be useful in identification of the aetiological agents of these diseases during their early phase, which may in turn be useful in development of better health care and appropriate treatment of suspected dogs, particularly in endemic regions.

Detection and Molecular Characterization of Babesia canis vogeli and Theileria annulata in Free-Ranging Dogs and Ticks from Shahriar County, Tehran Province, Iran

Background:

We aimed to detect and characterize vector-borne parasites of Babesia and Theileria in dog and ticks by PCR assay. Canine babesiosis is a significant tick-borne disease caused by different Babesia species. As the infection has not been reported in Shahriar region Tehran, Iran, molecular techniques allowed us to identify tick-borne parasites in asymptomatic dogs.

Methods:

The number of 40 dog peripheral blood samples and 27 skin attached ticks were analyzed by molecular PCR assay. The specific primers were used for detecting Babesia canis, B. gibsoni and T. annulata.

Results:

B. c. vogeli was detected in 10 dog blood samples (25%). Additionally, T. annulata infection was identified in 13 dog blood samples (32.5%) and 18 isolated tick DNAs (66.7%). The results of PCR were confirmed by 18S rRNA and Tams1 gene sequence analyzing and have been registered in GenBank under following accession numbers for B. c. vogeli (MH793502) and T. annulata (MK105284). Conclusion: The verification of T. annulata infection in free-ranging dogs and ticks shows dogs might be considered as important natural carriers/reservoirs for T. annulata in enzootic region for bovine theileriosis. The obtained data may be useful for veterinary practitioners and dog owners to aware of Babesia and Theileria infection in dog and tick to establish the effective preventive measures.

The red fox (Vulpes vulpes), a possible reservoir of Babesia vulpes, B. canis and Hepatozoon canis and its association with the tick Dermacentor reticulatus occurrence

The red fox (Vulpes vulpes) is known to be a reservoir host of various vector-borne protozoan parasites. Yet, the impact of these parasitic infections on the health status of the red fox is unknown. In this study, we compared the prevalence of haemoprotozoa in juvenile and adult foxes from four regions in Poland. The abundance of questing adult Dermacentor reticulatus ticks was shown to differ between regions and include a tick-endemic and non-endemic region, as well as two zones in which D. reticulatus recently expanded: an eastern and a western zone. Spleen and kidney enlargement indices were compared between infected, co-infected and non-infected foxes to evaluate pathogenic output of parasitic infections. Blood samples were collected from 383 necropsied red foxes and 25 live-trapped red fox cubs. The weights of spleens, kidneys and bodies were recorded for each necropsied individual. Blood and spleen DNA samples were screened by PCR to detect 18S rRNA and cox1 gene fragments of Babesia spp., and 18S rRNA of Hepatozoon spp. Prevalence of infection and mean organ weight indices were compared in relation to fox age and sex, origin (zone) and infection status. Hepatozoon canis (174/381; 45.7%) and Babesia vulpes (117/381; 30.7%) were the dominant pathogens infecting adult foxes. Babesia canis DNA was detected in 9 (2.4%) individuals. Two fox cubs from Western Poland were infected with B. vulpes (2/14; 14%), while H. canis infection (16/25; 59%) was detected in cubs from all three regions where trapping was carried out. Infection with B. vulpes was associated with significantly higher weights of spleens and kidneys. Spleen weight/ body weight and mean kidney weight/ body weight indices were shown as relevant in evaluating changes occurring during infection with B. vulpes. Babesia and Hepatozoon spp. infections differed in red foxes from D. reticulatus-endemic, non-endemic and newly inhabited areas. The prevalence of B. canis in foxes from four regions of Poland reflects the prevalence recorded in questing adult D. reticulatus collected in these areas. This finding suggests a contribution of red foxes to the establishment of new foci of B. canis-infected D. reticulatus ticks in areas recently invaded by this tick species. Spleen and kidney enlargement was identified in foxes infected with B. vulpes, particularly in individuals co-infected with B. vulpes and H. canis.

Detection of tick-borne pathogens in Rhipicephalus sanguineus sensu lato and dogs from different districts of Portugal

Dogs are highly exposed to pathogens transmitted by ectoparasites. The Mediterranean climate of Southern Europe, together with the presence of stray and/or neglected pets in close proximity with humans, contribute for tick expansion and stand for increased risk to infections in humans due to the zoonotic potential of many of these agents. The aim of this study was to perform a molecular survey in dogs (suspected of tick-borne disease and/or infested with ticks), as well as in ticks collected from those animals, from 12 districts of Portugal to investigate the occurrence of Rickettsia spp. and other tick-borne pathogens (Babesia, Ehrlichia, Anaplasma and Hepatozoon). Additionally, a serological survey of spotted fever group Rickettsia in Portuguese dogs was performed using an in-house immunofluorescence assay (IFA). A total of 200 whole-blood samples and 221 Rhipicephalus sanguineus s. l. ticks were collected from dogs. A total of 14 (7 %) blood samples and 10 (4.5 %) ticks yielded presumptively positive 420-bp amplicons using the Rickettsia spp. partial ompB nested PCR. Screening of the ompB-positive samples using the gltA gene showed 8 positive ticks. All Rickettsia ompB and gltA sequences had the highest identity with R. massiliae. The Rickettsia-positive dogs were further tested for other tick-borne pathogens and were found to be infected with Babesia spp. (n = 5), but not with Ehrlichia, Anaplasma or Hepatozoon. Of the 149 dog serum specimens tested in the serological assay, 103 (69 %) were positive for IgG antibodies against spotted fever group Rickettsia. Antibodies were found in dogs from all the studied districts, in 55 (53 %) of the stray and in 48 (47 %) of the owned dogs. Our study detected and characterized for the first time R. massiliae in dogs from Portugal, broadening the geographical range of this canine pathogen and adding knowledge to the impact of this disease in dogs.

Clinicopathological and molecular profiles of Babesia vogeli infection and Ehrlichia canis coinfection

BACKGROUND AND AIM

Canine babesiosis, a tick-borne parasitic disease, is caused by the hemoprotozoa, Babesia vogeli, and Babesia gibsoni. Infection with these parasites, which is endemic globally, leads to life-threatening immunosuppression in dogs. The merozoites invade the red blood cells (RBCs) of infected dogs. Ehrlichia canis, an intracellular bacterium that infects monocytes, is transmitted by the same tick species (Rhipicephalus sanguineus) during blood consumption and coinfection with B. vogeli and E. canis has been reported. Although the hematology and biochemistry of canine babesiosis have been studied, more studies are needed to develop a better understanding of the hematobiochemical and molecular profiles associated with cases of single infection and coinfection of canine babesiosis in Thailand. This study aimed to investigate the hematological, biochemical, and molecular profiles of B. vogeli infection and E. canis coinfection.

MATERIALS AND METHODS

The study included 33 B. vogeli-positive blood samples and 11 E. canis-coinfected blood samples. To exclude coinfection with Hepatozoon canis and Anaplasma platys, only dogs with B. vogeli infection and B. vogeli-E. canis coinfection were included in the study. A multiplex polymerase chain reaction (PCR) assay was conducted to detect B. vogeli, E. canis, and H. canis, and a conventional PCR assay was conducted for the detection of A. platys. Besides, the PCR assay and sequencing, comprehensive data analysis was conducted, including a microscopic blood parasite examination and hematological and biochemical data analysis.

RESULTS

The comparison of the hematobiochemical data between the B. vogeli-positive and E. canis coinfection groups identified that there were statistically significant differences in the RBC parameters, including RBC count, hemoglobin concentration, hematocrit, and RBC distribution width (p=0.001). Neither B. vogeli infection nor coinfection with E. canis was associated with the sex, breed, recorded clinical signs, geographic origin of the dog and also B. vogeli 18S rRNA gene sequencing results.

CONCLUSION

Coinfection with E. canis increased the severity of babesiosis. The pathogenic mechanisms underlying this infection, such as destruction of RBCs, require further investigation. This study may enhance diagnosis, treatment, and prevention of canine babesiosis.

Don't let sleeping dogs lie: unravelling the identity and taxonomy of Babesia canis, Babesia rossi and Babesia vogeli

For most of the 20th century the causative agent of canine babesiosis, wherever it occurred in the world, was commonly referred to as Babesia canis. Early research, from the 1890s to the 1930s, had shown that there were three distinctly different vector-specific parasite entities occurring in specific geographical regions, that host response to infection ranged from subclinical to acute, and that immunity to one stock of the parasite did not necessarily protect against infection with other stocks. This substantial body of knowledge was overlooked or ignored for 50 years. In this review the first records and descriptions of the disease in four geographical regions were traced: sub-Saharan Africa, Europe, North Africa and Asia. Research leading to identification of the specific tick vector species involved is documented. Evidence is given of the growing realisation that there were substantial biological differences between stocks originating from different geographical regions. Etymological provenance for Babesia vogeli is proposed.

Ehrlichia canis in dogs experimentally infected, treated, and then immune suppressed during the acute or subclinical phases

Background

Concerns for recrudescence of Ehrlichia canis infection arise when immunosuppressive drugs are used to treat immune‐mediated diseases in dogs previously infected with E. canis.

Objectives

Determine whether administration of prednisolone and cyclosporine would reactivate E. canis infection in dogs previously treated with doxycycline during the acute or subclinical phases.

Animals

Seven beagles previously experimentally infected with E. canis and administered doxycycline for 4 weeks were included. Three of the 7 dogs were incidentally concurrently infected with Anaplasma platys and Babesia vogeli and were administered 2 doses of imidocarb 2 weeks apart before enrollment in the current study.

Methods

Experimental study. Each dog was administered prednisolone and cyclosporine for 6 weeks. Clinical signs, complete blood cell count (CBC), polymerase chain reaction (PCR) assays for E. canis, A. platys, and B. vogeli DNA in blood, E. canis indirect fluorescent antibodies (IFA) titers, and flow cytometry for antiplatelet antibodies were monitored.

Results

All dogs completed the immunosuppressive protocol. No evidence for recrudescence of E. canis, A. platys, or B. vogeli were detected based on clinical signs or results of CBC, PCR, IFA, and flow cytometry for antiplatelet antibodies. E. canis IFA titers were negative in 5/7 dogs at the end of immunosuppressive protocol and were negative 6 months after the protocol in 5/5 dogs available for testing.

Conclusions and Clinical Importance

Dogs administered with a 4‐week course of doxycycline with or without imidocarb failed to show evidence of activation of E. canis infection after administration of a commonly used immune suppressive protocol.

The electrophoretic pattern of serum proteins in dogs with babesiosis

This study was aimed at the evaluation of the electrophoretic pattern of serum proteins in dogs naturally infected with Babesia canis. Blood samples were collected from 37 dogs infected with B. canis and showing clinical signs consistent with the disease. The sick animals were classified as dogs with physiologic and decreased red blood cell (RBC) values. Twenty-five healthy dogs formed the control group. The concentrations of total proteins and protein fractions were measured in blood serum. The values of total proteins, albumin and albumin/globulin (A/G) ratio in dogs with babesiosis were significantly lower than in healthy ones (P < 0.001). In the globulin fractions, significantly higher relative concentrations of α1-, β1- and β2-globulins (P < 0.01), and non-significantly higher values of α2- and γ-globulins were found in dogs with babesiosis with a double α2-zone in six out of 37 animals. Marked differences were observed also between the two groups of sick animals, with significantly lower values of albumin and A/G ratio (P < 0.05), and significantly higher values of α1- and β1-globulins in dogs with decreased RBC (P < 0.05 and P < 0.01, respectively). Presented results indicate marked alterations in the electrophoretic pattern of serum proteins in dogs with babesiosis suggesting its usefulness for the evaluation of pathophysiological changes caused by the disease and for diagnostic of disease severity.

Rapid identification of Babesia canis and Babesia gibsoni (Asian genotype) in canine blood samples using a customized portable real-time PCR analyzer and TaqMan-based assay

Canine babesiosis is a serious infectious disease in subtropical and tropical regions. Typically, clinical detection of canine babesiosis is performed by blood smear observation or the traditional polymerase chain reaction (PCR). Herein, we developed a new TaqMan-based real-time PCR assay combined with a customized portable real-time PCR platform for a rapid and accurate detection of canine babesiosis. Two new primer/probe pairs (B18S and BITS1) were designed based on 18S ribosomal RNA and an internal transcribed spacer 1 (ITS1) sequence to differentiate Babesia canis and B. gibsoni (Asian genotype) DNAs from canine blood samples. Additionally, a corresponding customized compact real-time PCR platform with low 6-carboxyfluorescein fluorescence detection (≤5 nM), including a fast and accurate thermal cycling ability with a user-friendly interface for thermal control and data analysis, was designed for the limited space use. Both assays (B18S and BITS1) demonstrated a sensitivity of 100 copies/reaction based on the 95 % confidence interval evaluation method. The self-developed customized portable real-time PCR analyzer presented high repeatability and reproducibility with the TaqMan-based assay. Moreover, 501 clinical specimens were collected for evaluating the performance of the proposed PCR. The positive and negative predictive values were 90 % (18 of 20) and 100 % (226 of 226), respectively, for samples suspected with B. canis infection and 98 % (55 of 56) and 100 % (199 of 199), respectively, for samples suspected with B. gibsoni infection.

Simultaneous Detection of Parasitic Vector Borne Diseases: A Robust Cross-Sectional Survey in Hunting, Stray and Sheep Dogs in a Mediterranean Area

Canine vector-borne diseases (CVBDs) are a spectrum of diseases caused by different pathogens transmitted by blood-feeding arthropoda. The aim of this study was to investigate leishmaniosis, babesiosis, and filarial infections in dogs with three different lifestyles (hunting, stray, and sheep dogs) in Molise, the smallest region of southern Italy, where data available about these parasitic infections are very scant. A cross-sectional survey was conducted on 318 hunting, 180 stray, and 218 sheep dogs. Immunofluorescence antibody test, blood smear, molecular techniques and Knott's test were performed to detect Leishmania infantum, Babesia spp. and filarial nematodes. Association between positivity to CVBDs, age, sex, and living conditions was evaluated. An overall prevalence of 12.3% of CVBDs caused by L. infantum (10.2%), B. canis canis (0.3%) and filarial nematodes (2.1%) was detected. Three dogs showed co-infections of L. infantum and B. c. canis (0.1%) or Acanthocheilonema reconditum (0.3%). A significantly association was found only for filarial infection in hunting dogs. These parasites were reported also in dogs without clinical signs. It is very important to plan effective control programs for CVBDs to guarantee not only the health and welfare of pets, but also the public safety, because some of mentioned parasites are of zoonotic importance.

A short-term and long-term relationship between occurrence of acute canine babesiosis and meteorological parameters in Belgrade, Serbia

Belgrade, the capital of the Republic of Serbia, is an endemic location for canine babesiosis caused by Babesia canis. This tick-borne disease occurs seasonally in regions with moderate continental climate. However, recent clinical data show that: 1) some cases of canine babesiosis have been recorded during the winter, and 2) canine babesiosis is spreading to the northern parts of Europe with a colder climate, which is a region previously free of this disease. Our study investigates the occurrence of canine babesiosis in different seasons over 2013-2016, and explores a short-term link between meteorological parameters and number of diagnosed cases of canine babesiosis in Belgrade. It also looks into possible long-term correlations that span one year before the onset of the disease. Based on 872 recorded cases over four years, our results show a bimodal seasonal distribution of canine babesiosis, with a pronounced peak in the spring, and a less conspicuous one in the autumn. Throughout the year, even over the coldest and warmest periods, there is a broad range of temperatures and relative humidities when the disease is recorded. Over one year prior to the spring and autumn onset of the disease, we found a noticeable impact of temperature and relative humidity, and to a lesser extent, of atmospheric pressure and cloud cover, on the number of diagnosed cases. These findings imply short-term and long-term relationships between occurrence of acute canine babesiosis and certain meteorological parameters, and they open further questions that need to be investigated in order to understand the epidemiology of this disease.

Canine babesiosis among working dogs of organised kennels in India: A comprehensive haematological, biochemical, clinicopathological and molecular epidemiological multiregional study

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First holistic study on canine babesiosis among working dogs from India.

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B. gibsoni babesiosis is posing a diagnostic & therapeutic challenge in this country.

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Atypical babesiosis (MODS, DIC) are being maidenly documented from this country.

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Simple PCR assay results were statistically found to be significantly false negative.

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Nested PCR assay to be relied upon as screening and for epidemiological studies.

Canine babesiosis is a serious disease among tick-borne haemoprotozoan diseases, globally. The present study was envisaged for carrying out thorough investigation of the disease among working dogs of organised kennels situated in different agro-climatic zones of India as comprehensive understanding of the disease from this country was pertinently lacking. During the study period of three years (2012–2014), 330 dogs suspected for babesiosis were examined for clinicopathology by their physical examination, haematological and biochemical parameters estimation, while the detection of apicomplexan parasites was confirmed by using various diagnostic techniques i.e. by conventional microscopy, by two different Babesia specific 18S rRNA based PCR protocols (conventional/simple PCR and nested PCR assays) followed by sequencing of obtained PCR amplicons for Babsesia spp. identification. Out of 330 clinical cases screened 5.15% (17/330), 9.09% (30/330) and 15.45% (51/330) were found to be positive in microscopic examination, simple- and nested- PCR assay, respectively. Comparative statistical analyses of these diagnostic assay results revealed that significant difference exists among the three diagnostic methodologies and thus it is recommended that the nested PCR technique be relied upon as a screening molecular assay and also for epidemiological studies of the disease in this country. Phylogenetic analysis based on 18S rRNA depicted the monophyletic nature and clonal expansion among all the B. gibsoni, under study. Sequencing results of PCR amplicons revealed that B. gibsoni has predominantly established itself over B. vogeli as former was incriminated in 47 cases while latter was confirmed in only four animals. Based on the clinical severity, these 51 affected animals were classified into three main groups’ of 17 animals each viz., apparently healthy-, simple or uncomplicated babesiosis- and atypical or complicated babesiosis- group. Haematological and biochemical profiling of these dogs confirmed the characteristics findings of infection by both the Babesia spp. It was observed that the infection by small form of Babesia (B. gibsoni) is posing a significant therapeutic challenge and chemosterilization by commonly prescribed anti-protozoal drugs was not achieved as clinical relapses were often observed. The clinical signs, sequence based confirmation and severity of the infection suggested that there is a positive selection of B. gibsoni (smaller form) over B. vogeli (larger form) in this country and raises serious concerns as prognosis in former is considered to be poor compared to latter. Thus, these findings have opened new paradigms for planning of pragmatic control strategies against this emerging canine health problem.

ACVIM consensus statement on the diagnosis of immune-mediated hemolytic anemia in dogs and cats

Immune-mediated hemolytic anemia (IMHA) is an important cause of morbidity and mortality in dogs. IMHA also occurs in cats, although less commonly. IMHA is considered secondary when it can be attributed to an underlying disease, and as primary (idiopathic) if no cause is found. Eliminating diseases that cause IMHA may attenuate or stop immune-mediated erythrocyte destruction, and adverse consequences of long-term immunosuppressive treatment can be avoided. Infections, cancer, drugs, vaccines, and inflammatory processes may be underlying causes of IMHA. Evidence for these comorbidities has not been systematically evaluated, rendering evidence-based decisions difficult. We identified and extracted data from studies published in the veterinary literature and developed a novel tool for evaluation of evidence quality, using it to assess study design, diagnostic criteria for IMHA, comorbidities, and causality. Succinct evidence summary statements were written, along with screening recommendations. Statements were refined by conducting 3 iterations of Delphi review with panel and task force members. Commentary was solicited from several professional bodies to maximize clinical applicability before the recommendations were submitted. The resulting document is intended to provide clinical guidelines for diagnosis of, and underlying disease screening for, IMHA in dogs and cats. These should be implemented with consideration of animal, owner, and geographical factors.

Development and validation of a multiplex, real-time PCR assay for Babesia rossi and Babesia vogeli

Canine babesiosis is caused by tick-transmitted intraerythrocytic protozoan parasites occurring worldwide. In southern Africa, babesiosis is caused by Babesia rossi and B. vogeli and is one of the most common and important infectious diseases affecting dogs. There is no reliable, rapid and sensitive method for the detection of these parasites, especially when parasitaemia is low. The aim of this study was to develop a sensitive and specific multiplex TaqMan® MGB PCR assay for the diagnosis of canine babesiosis infections occurring in southern Africa, and to discriminate between Babesia rossi and B. vogeli. The fitness of purpose of the assay was to confirm diagnosis of suspect or clinical cases, and estimate prevalence of infection for research purposes. A total of 648 published sequences were used to design the assay. A set of group-specific canine Babesia spp. primers were designed to amplify a 117 nucleotide region of the 18S rRNA gene of all canine Babesia spp. Species-specific TaqMan® MGB probes were developed for B. rossi, B. vogeli, B. canis and B. gibsoni, but analytical validation was only performed for B. rossi and B. vogeli as a multiplex assay. The assay had a broad dynamic range and amplified B. rossi and B. vogeli efficiently (98.6% and 94.7% respectively). The assay was sensitive, with a 95% LOD of 10^-2.67% parasitized erythrocytes (PE) for B. rossi and 10^-2.03% PE for B. vogeli, and specific, with no cross reaction between B. rossi and B. vogeli and no detection of other haemoparasites that infect dogs, such as Ehrlichia canis and Anaplasma platys. Consistent repeatability within and between PCR runs was shown. This assay will be able to accurately and rapidly confirm babesiosis in canines and allow for treatment to be administered in the early stages of the disease, speeding up the recovery time in affected dogs.

An annotated checklist of tick-borne pathogens of dogs in Nigeria

Tick-borne pathogens are transmitted by the bite of a tick vector or the ingestion therein by a susceptible host. Conventionally, the diagnosis of tick-borne parasites in Nigeria is achieved through the demonstration of their developmental stages in the host's blood or tissues. These classical methods are limited in their capability to detect chronic cases or healthy carriers and to differentiate between pathogens of similar morphological features. Molecular diagnostic techniques of high sensitivity have been developed to overcome these shortfalls by detecting the pathogen's DNA, elucidating their genetic makeup and comparing their phylogenetic relationship to other pathogens, sometimes necessitating taxonomic changes. Detection of DNA of canine tick-borne pathogens (CTBPs) such as Ehrlichia canis, Hepatozoon canis, and Mycoplasma haemocanis has been reported in Nigerian dogs corroborating earlier microscopic findings. Furthermore, DNA of Anaplasma platys, Ehrlichia ewingii, 'Candidatus Mycoplasma haemobos' and Theileria sp. hitherto considered to be absent in Nigeria has been detected, thereby expanding the spectrum of CTBPs in the country. However, in some cases, diagnoses based on the detection of single short DNA fragments from pathogens can cause considerable confusion. This occurred in the case of the large canine Babesia, previously referred to as Babesia canis which has been reported in Nigerian dogs. There appears to be confusion regarding the accurate status of this pathogen in Nigeria due to the subsequent classification into Babesia canis, Babesia vogeli and Babesia rossi. Moreover, several molecular studies failed to detect the DNA of Babesia gibsoni previously reported in Nigerian dogs by light microscope. These findings necessitate regular update of the list of CTBPs of veterinary and medical importance, in order to keep practitioners abreast with these changes. Herein, an annotated checklist of tick-borne pathogens of dogs in Nigeria, based on available data from both classical and molecular studies, with notes explaining any discrepancies between the methods and probable explanations thereof, is presented.

A comprehensive review on past, present and future aspects of canine theileriosis

Canine theileriosis is a notorious tick borne piroplasmid infection of wild and domestic canines. The causative agent has not yet been accurately classified. PCR studies revealed that causative agent resembles to Theileria genus and thus provisionally named as Theileria annae. The other Theileria species reported in canines is Theileria annulata, Theileria equi and unnamed Theileria specie. This emergent canine infection is considered to be endemic in most of the European countries. However in Asia this disease has not been reported till date. The vectors responsible for transmission of this disease have not been determined. It has been suggested that DNA of Theileria annae has been detected in hard tick Ixodes hexagonus in Northwestern Spain and several other tick species. Clinically canine theileriosis is characterized by severe weakness, fever, hemoglobinuria and anemia. Recently atovaquone or buparvaquone plus azithromycin therapy showed better clinical efficacy. This comprehensive review is intended to summarize the current knowledge on prevalence and epidemiology of canine theileriosis in different countries of the world and associated tick vectors.

Frequency of Babesia vogeli in domestic dogs in the metropolitan area of Piura, Peru

The aim of this study was to assess the presence of piroplasms in dogs in the metropolitan region of the city of Piura, Peru. Two hundred and twelve canine blood samples were randomly collected. The deoxyribonucleic acid was extracted from each blood sample and was tested using the polymerase chain reaction, restriction fragment length polymorphism and sequence analyses. The study showed the occurrence of Babesia vogeli. For the first time, this approach revealed the presence of canine babesiosis caused by B. vogeli in Peru. This highlights the need to test for pathogens that might be responsible for causing canine babesiosis, through using proper molecular tools.