Hepatozoon Canis In Dogs Research Articles

A review of Hepatozoonosis caused by Hepatozoon canis in dogs.

Hepatozoon canis is a type of single-celled organism is spread by ticks and commonly affects dogs. It is responsible for causing one of the most significant parasitic diseases in dogs, called Hepatozoonosis. It is considered one of the most common causes of canine vector-borne diseases because it is closely linked to Rhipicephalus sanguineus (the brown dog tick), a species found worldwide. Hepatozoonosis caused by H. canis is prevalent in regions such as South Europe, South America, Asia, and Africa. H. canis often causes emaciation, anemia, and intermittent fever in infected dogs. The drugs used to treat H. canis infection in dogs include the combination of imidocarb dipropionate with doxycycline, toltrazoril, tetracycline hydrochloride, and the combination of trimethoprim-sulfamethoxazole.The primary solution to prevent the spread of infections caused by H. canis is to control the population of R. sanguineus ticks because H. canis is spread through ticks. This review aims to provide a brief overview of various studies conducted on the morphology, life cycle, hosts, epidemiology, clinical symptoms, laboratory diagnosis, autopsy findings, differential diagnosis, treatment, and prevention methods of H. canis.

Ocorrência de patógenos transmitidos pelo carrapato Rhipicephalus sanguineus sensu lato em cães na região semiárida do estado do Rio Grande do Norte, Brasil

ABSTRACT: The aim of this study was to determine the occurrence of infection by Ehrlichia canis, Anaplasma platys, Babesia vogeli, and Hepatozoon canis in dogs from the semiarid region of Rio Grande do Norte state. Also, we evaluated the characteristics that favor the infection by E. canis and the presence of Rhipicephalus sanguineus s.l. ticks. For that, 120 dogs were included, from which blood samples were collected for DNA extraction and molecular diagnosis of these four pathogens. Anamnesis and physical examination were performed on each patient, and all properties were characterized. Chi-square and Fisher’s exact tests were used to verify the association of the studied variables. The most prevalent pathogen in the study was E. canis (13.3%), followed by A. platys (11.7%), H. canis (6%) and B. vogeli (6%). Correspondence analysis performed between E. canis positivity and the variables studied showed the influence of factors such as tick history, non-vaccination and non-use of antiparasitic medications. The main environmental factor observed in the infection by E. canis was the presence of trees and vegetation in the residences. Recognizing these characteristics can help elaborate prevention and control strategies since environmental management activities seek to reduce the interaction between vector and host and, consequently, the exposure to diseases.

The first report on Hepatozoon canis in dogs and wolves in Poland: clinical and epidemiological features

BackgroundCanine hepatozoonosis caused by Hepatozoon canis is a common infection in dogs, with frequent case reports from the Mediterranean region and more recently from several Central European countries, such as Hungary and Germany. Despite the high prevalence of H. canis in red foxes, no infections have been reported to date in dogs in Poland. We describe here the first autochthonous cases of H. canis infection in dogs, including their clinical features, and report the prevalence of H. canis in grey wolves from different regions of Poland.MethodsThin smears prepared from blood samples collected from dogs were evaluated by microscopic examination. A total of 60 wolves and 47 dogs were tested. Infections were confirmed by PCR and sequencing.ResultsGamonts of H. canis were found in > 50% of the neutrophils of two dogs and in < 10% of the neutrophils in another five dogs. Molecular typing by PCR sequencing of the 18S ribosomal RNA gene fragment confirmed infections in 11 dogs from different regions of Poland, in 2.7% of dogs attending veterinary practices in central Poland and in 35% of wolves from various geographical regions of Poland. Clinical features manifested mostly in older dogs, and the most common signs were anaemia and apathy. Young dogs usually remained asymptomatic.ConclusionsThis is the first report of H. canis infection in dogs and wolves in Poland. Although the exact vector of the parasite is not known, veterinary practitioners should be aware of this new parasitosis and should consider appropriate diagnostics to confirm/exclude this infection. Further studies are needed to understand the transmission routes of H. canis in domestic and wild canids in Poland.Graphical

Autochthonous infection with Ehrlichia Canis and Hepatozoon Canis in dogs from Serbia.

The epidemiological status concerning many canine tick-borne diseases (TBDs) in Serbia is still insufficiently known. Our study aimed to investigate the presence of tick-borne pathogens of the family Anaplasmataceae and Hepatozoon spp., as a cause of illnesses accompanied by clinical signs that can occur in dogs with anaplasmosis, ehrlichiosis and hepatozoonosis. Dogs are included in the study based on the presence of a minimum of three clinical and/or pathological findings that could be associated with anaplasmosis, ehrlichiosis and hepatozoonosis. During the study (April-October 2018), 11 dogs met the conditions to be included in the survey. Identification of the causative agent in the blood of diseased dogs was performed by conventional PCR followed by sequencing. The presence of the pathogens was confirmed in three animals (3/11, 27.3%). The presence of Ehrlichia canis was confirmed in 3-month-old female Rottweiler puppy, an 8-year old Miniature Schnauzer female was positive for Hepatozoon canis infection, while 4-year-old mixed breed male dog was co-infected with both mentioned pathogens. These are the first cases of autochthonous infection with E. canis and H. canis in dogs from Serbia confirmed by molecular methods. The results of our study indicate the importance of molecular methods to establish a reliable diagnosis of TBDs. Also, the confirmed presence of causative agents of canine monocytic ehrlichiosis and hepatozoonosis in Serbia appeals to veterinary practitioners that it is necessary to exclude the presence of those diseases in suspicious dogs.

Clinical, diagnostic and epidemiological implications of Hepatozoon spp., Babesia spp. and Leishmania infantum infection in cats and dogs in a Mediterranean periurban setting

Hepatozoon spp., Babesia spp. and Leishmania infantum are common parasites of dogs in Mediterranean countries and are less frequent in cats, particularly Babesia spp. and L. infantum. Moreover, there is limited information on coinfections between these parasites and on L. infantum’s distribution in blood, skin and lymphoid tissue in cats. We used PCR and DNA sequencing to investigate the prevalence of these parasites and the aetiology of Hepatozoon spp. and Babesia spp., in blood, skin, spleen and lymph node samples from up to 212 stray cats and 82 abandoned dogs in southeast Spain. All except 2 dogs were healthy; instead, 112 cats had clinical signs. The estimated PCR prevalences (95% confidence interval) were 25% (19–31%) Hepatozoon felis in cats, 13% (6–21%) Hepatozoon canis in dogs, 1% (0–4%) Babesia vogeli in dogs, 0% Babesia spp. in cats and 21% (15–26%) and 44% (33–55%) L. infantum in cats and dogs, respectively, and infections were not associated with each other. Leishmania infantum prevalence in lymphoid tissue was significantly higher in dogs than in cats (p < 0.001), and dogs had higher parasite loads than cats (p = 0.012). Moreover, L. infantum prevalence was significantly higher in the skin and lymphoid tissue compared to blood in infected, asymptomatic animals but it was similar in cats with clinical signs, which also had higher parasite loads compared to infected, asymptomatic cats (p < 0.05). The study highlights significant differences between sympatric dogs and cats with respect to the parasite infections investigated, as well as the need to examine both lymphoid tissue and skin samples to maximise the sensitivity of L. infantum infection diagnosis.

Molecular Epidemiology, Characterisation of Hepatozoon canis in Dogs as well as in Ticks and Haemato-biochemical Profile of the Infected Dogs in Chennai

Background: Canine hepatozoonosis is caused by Hepatozoon canis and is transmitted through ingestion of an ixodid tick, Rhipicephalus sanguineus sensu lato containing mature oocysts. Periodical screening of vectors and their host for the presence of pathogen acts as reliable method for understanding the pattern of the disease which thereby reduces the chance of disease and the cost of treatment. Methods: A total of 482 blood samples and 47 pooled tick samples collected from 482 dogs during the study period were screened through conventional and molecular techniques for the presence of H. canis. The haematology and biochemical profile of infected animals were evaluated. Positive PCR products were sequenced, compared with the existing sequences and were analysed phylogenetically. Result: Out of 482 blood samples collected from dogs, only 5 were found to be positive microscopically for H. canis while 32 blood samples and 8 tick samples were found positive by polymerase chain reaction (PCR). Amongst epidemiological attributes, age and gender were found to have no significant relationship for the occurrence of the disease while, breed of the dog had a significant association. Haematology and biochemistry revealed profound anaemia, monocytosis and elevated blood urea nitrogen in dogs with H. canis.

A Molecular survey of Hepatozoon canis in dogs in the Siirt province of Turkey

This study aimed to determine Hepatozoon canis prevalence in dogs in the Siirt province of Turkey by the molecular method. The animal material of the study consisted of a total of 75 dogs that appeared clinically healthy. Two ml of blood sample were taken from the vena cephalica antebrachii. Then, DNA extraction was performed. Polymerase chain reaction (PCR) was performed to amplify the 666 bp 18S rRNA gene region of Hepatozoon canis. Two positive PCR products were purified and sequenced. As a result of Nested-PCR, H. canis specific bands in 666 bp size were obtained in 7 (9.33%) out of 75 dogs. The result of sequence analysis, the nucleotide sequence was registered in the NCBI GenBank database with accession numbers OL467380.1-OL467538.1. Hepatozoon canis registered in GenBank of sequence OL467380.1 was found to be similar with other H. canis strains of registration numbers MW684292.1 with 99.69% and MH615006.1-MK091085.1-MF797806.1 with 99.53% rates; and the sequence with registration number OL467538.1 was found to be similar to the series MW684291.1 with 99.09% and MH615006.1-MK091085.1-KX 818220.1 with 99.08% rates by BLAST analysis. Hepatozoon canis prevalence of dogs in the Siirt province was determined as a result of this study. It is of great importance to take preventive measures, especially to fight ticks with appropriate acaricides, since there is no vaccine to prevent the disease.

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.

Identical 18S rRNA haplotypes of Hepatozoon canis in dogs and foxes in Brandenburg, Germany

Hepatozoon canis is a blood parasite of the suborder Adeleorina infecting wild and domestic canids. Transmission occurs by oral uptake of Rhipicephalus sanguineus sensu lato vector ticks infected with H. canis, but vertical transmission is also assumed to be possible. In German foxes, a high prevalence of H. canis has previously been reported despite the fact that R. sanguineus s.l. is not endemic. In the absence of knowledge about local transmission pathways, foxes should be considered to be possible reservoirs of H. canis and contribute to infection of domestic dogs. The present study aimed to determine how often foxes and dogs are infected in Brandenburg (Germany) and if identical or different H. canis 18S rRNA haplotypes are found in these host species. Hepatozoon spp. were detected by PCR in 46/1050 (4.4 %) of dog blood and 176/201 (77.6 %) of fox spleen samples from Brandenburg. Sequencing of 19 dog and 56 fox samples identified all as H. canis. For nine positive dogs, owners stated that they had never left Germany suggesting that autochthonous transmission occurs not only in foxes but also in dogs. Sequences for seven of these possible autochthonous cases were obtained and six were identical to the predominant haplotype found in the foxes. Haplotype network analysis confirmed that many dogs, including some without travel history, carried the same or very similar 18S rRNA haplotypes as the foxes suggesting that both hosts participate in the same epidemiological cycle.

Molecular detection of Hepatozoon canis in dogs and ticks in Shaanxi province, China

Hepatozoon canis, transmitted by Rhipicephalus sanguineus, is a tick-borne pathogen and causes canine hepatozoonosis. Until now, only limited previous studies were conducted on the molecular detection and characterization of Hepatozoon sp. in dogs in China. Blood samples were collected from 93 sick dogs that were clinically diagnosed as babesiosis but tested negative for Babesia, and 103 apparently healthy dogs, as well as their infesting ticks in Xi’an and Hanzhong cities, Shaanxi province of China. PCR amplifying partial 18S rRNA gene was used to detect the DNA of Hepatozoon sp. Genetic and phylogenetic analysis were performed to determine the Hepatozoon species. Our results demonstrated that H. canis was identified from the sick dogs and the infested ticks in Hanzhong, with no significant differences of prevalence between both genders and ages. No positive blood or tick samples were found in Xi’an. Moreover, all the 18S rRNA gene sequences recovered from both dogs and the infested ticks showed a high genetic similarity with each other, and also presented a close relationship with other known sequences in and outside China. In conclusion, H. canis was identified in babesiosis-suspected dogs and ticks infesting them in Shaanxi, China, although the association between clinical signs and H. canis need further study.

DETECTION OF BLOOD PROTOZOA IN PET DOGS IN NINEVEH PROVINCE

Through out this study we collected 54 blood samples from the cephalic vein of dogs. They were all obtained from indoor breeding from both sexes and were of different ages and different breeds. Blood smears were prepared, stained with Giemsa stain and examined under the light microscope to detect blood parasites. The result of clinical examination of dogs showed different clinical signs which included nervous signs, weakness, haemglobinurea and Enlargement of lymph nodes, whereas others did not show any clinical signs. The clinical signs combined with presence of blood protozoa which included Babesia gibsoni, B.canis, Trypanosoma evansi, Hepatozoon canis, the high infection rate was recorded in Babesia (31.4%); while the lowest infection rate was recorded in Trypanosoma evansi (11.2%) Our results detected Hepatozoon canis in dogs (20.3%), Some cases showed mixed infection with Trypanosoma evansi and Hepatozoon canis. A higher infection rate was found in older age with a significance of variance p <0.05) and large breeds showed higher infection rate than small breeds. We conclude that the pet dogs recorded high infective rate with blood protozoa and recommended the owner to use antiprotozoal drugs and ectoparasites spots and test the animal periodically in veterinary clinic to identify the infection early. In conclusion, a high rate of infection with blood parasites was found in pet dogs. Vegular testing and routine treatment program of with antiprotozoal drugs and anti-parasitic drugs should be used a control measure.

Molecular detection of Hepatozoon canis in dogs from Kerala.

India has a wide range of agro-climatic zones which is highly conducive for a diverse range of vectors and canines are continuously exposed to the risk of spectrum of tick borne protozoan diseases. The brown dog tick, Rhipicephalus sanguineus is widely prevalent among dogs in Kerala and there is a high prevalence of this tick transmitted Babesia and Ehrlichia spp. infection. However, the incidence of Hepatozoon canis transmitted by the same tick species had not been reported in the state since 2004. Preliminary screening of client owned dogs revealed six dogs to be positive for typical gelatin capsule shaped gamonts of H. canis within neutrophils in blood smear by microscopic examination. A PCR assay was standardized to amplify a specific 737bp fragment of 18S rRNA gene of H. canis. Phylogenetic analysis revealed closest relationship with West Indies isolate deposited at GenBank database. The present study records the molecular detection of this haemoparasite in the state, for the first time.

Molecular Survey of Hepatozoon canis in Dogs from Samsun Province of Northern Part of Turkey

We attempt to address new information of haematozoan infections in dogs from Samsun province of Turkey. The diagnostic techniques using genus specific polymerase chain reaction designed to amplify a fragment of ∼666 bp located in 18S ribosomal RNA (rRNA) gene of Hepatozoon spp. include microscopic investigations. H. canis identities were confirmed by sequencing the 18S rRNA gene. Two hundred (170 stray and 30 owned dogs) blood samples from asymptomatic dogs treated for endo and ecto parasites were examined. There were no detected ticks on dogs in the clinical examinations. None of 200 thin blood smears were positive for the presence of Hepatozoon spp. gametocytes. Only one dog sample from 200 with a prevalence of 0.5% was found to be positive for the presence of Hepatozoon DNA demonstrates a chronic infection. Partial sequences of the 18S rRNA gene shared 99-100% similarity with the corresponding H. canis isolates. Contrary the other molecular surveys on H. canis among Turkey, this research revealed a very low prevalence of H. canis in dogs from Samsun province of Turkey, and it indicates that ectoparasite control programs have a great impact on decreasing the vector borne parasitic diseases especially in the stray and owned dogs.

Autochthonous Hepatozoon infection in hunting dogs and foxes from the Czech Republic.

Blood samples from 21 red foxes (Vulpes vulpes) and 8 hunting dogs from the same locality in the Czech Republic were examined for presence of Hepatozoon canis/Hepatozoon sp. The dogs were selected based on their close contact with foxes during fox bolting and because they had not traveled into known endemic areas. Using diagnostic PCR amplifying partial 18S rDNA fragment, Hepatozoon DNA was detected in 20 red foxes (95%) and 4 dogs (50%). From 8 positive foxes and 2 positive dogs, we obtained nearly complete 18S rDNA sequences. Phylogenetic analyses of these sequences revealed very low variability. Buffy coat smears from positive dogs were prepared and examined. No Hepatozoon gamonts were found. This study provides the first report of autochthonous infection of H. canis/Hepatozoon in dogs and foxes from the Czech Republic. Our study indirectly demonstrates cross infection between red foxes and dogs and confirms autochthonous infection of Hepatozoon canis in dogs living in a geographic area well outside the range of Rhipicephalus sanguineus sensu lato, which is so far the only known vector of H. canis in Europe.

Molecular identification of Hepatozoon canis in dogs from Campo Grande, Mato Grosso do Sul, Brazil.

The aim of this study was to investigate the occurrence of Hepatozoon species infecting dogs in the municipality of Campo Grande, Mato Grosso do Sul (MS), Brazil, using blood samples (n = 165) drawn from dogs. The species Hepatozoon canis was identified in 3.63% of the tested animals using molecular tools. Further studies are needed to determine the clinical relevance of this infection and the main arthropod vectors involved in its transmission.

Prevalence and molecular characterization of Hepatozoon canis in dogs from urban and rural areas in Southeast Brazil

The objective of this survey was to investigate the prevalence of Hepatozoon infection in dogs in the rural and urban areas of Uberlândia, Brazil by PCR and molecular characterization. DNA was obtained from blood samples collected from 346 local dogs from both genders and various ages. Seventeen PCR products from positive blood samples of urban dogs and 13 from the rural dogs were sequenced. Partial sequences of the 18S rRNA gene indicated that all 30 dogs were infected with Hepatozoon canis similar in sequence to H. canis from southern Europe. Four local dog sequences were submitted to GenBank (accessions JN835188; KF692038; KF692039; KF692040). This study indicates that H. canis is the cause of canine hepatozoonosis in Uberlândia and that infection is similarly widespread in rural and urban dogs.

Prevalence of &lt;i&gt;Babesia canis&lt;/i&gt; and &lt;i&gt;Hepatozoon canis&lt;/i&gt; in Zaria, Nigeria

The study was carried out to show the prevalence of Babesia canis and Hepatozoon canis in dogs within Zaria. Between the months of May and August 2010, blood samples collected from 150 dogs were processed using Giemsa stained thin blood smear and examined for the presence of B. canis and H. canis. Of the 150 dogs sampled, 84 (56%) were males and 66 (44%) were females. 106 (70.7%) were adults aged 1 year and above while 44 (29.3%) were dogs below the age of 1 year. Local breeds numbered 111 dogs constituting (74%) of the total number sampled, while 20 (13.3%) and 19 (12.7%) were foreign and cross breed respectively. One hundred and five (70%) of all dogs sampled were unconfined while 45 (30%) were confined. B. canis and or H. canis occurred in 26(17.3%) dogs, of which 10(38.5%) and 12(46.2%) had single infection of the former and later respectively, while 4(15.4%) had mixed infections of both parasites. The occurrence of the haemoparasites was significantly higher (X2 = 12.20, p &lt; 0.05, OR= 4.467) in younger dogs than in the adults, but there was no statistically significant association between the occurrence of the parasites and the breed (X2 = 0.3794, p &gt; 0.05) or sex (X2 = 1.237, p &gt; 0.05) of the sampled dogs. All the infected dogs were as well infested by the tick vector Rhipicephalus sanguineus with the non-confined dogs having significantly higher (X2 = 37.93, p &lt; 0.05) tick infestation rates. The infestation rates in both confined and non-confined groups had no statistically significant association to the respective levels of haemo-parasitism.(X2 = 0.1410, p &lt; 0.05, OR= 1.24).Keywords: Babesia canis, Dogs, Hepatozoon canis, Prevalence, Zaria.

Molecular characterization of Hepatozoon canis in dogs from Colombia

Hepatozoonosis is a tick-borne disease whose transmission to dogs occurs by ingestion of oocysts infected ticks or feeding on preys infested by infected ticks. Until now, there is no previous report of molecular characterization of Hepatozoon sp. in dogs from Colombia. EDTA blood samples were collected from 91 dogs from central-western region of Colombia (Bogotá, Bucaramanga, and Villavicencio cities) and submitted to 18S rRNA Hepatozoon sp. PCR and blood smears confection. Phylogenetic analysis was used to access the identity of Hepatozoon species found in sampled dogs. From 91 sampled dogs, 29 (31.8%) were positive to Hepatozoon sp. (25 dogs were only positive in PCR, 1 was positive only in blood smears, and 3 were positive in both blood smears and PCR). After sequencing, the found Hepatozoon sp. DNA showed 100% of identity with Hepatozoon canis DNA isolates. The phylogenetic tree supported the identity of the found Hepatozoon sp. DNA, showing that the isolates from Colombia were placed in the same clade than other H. canis isolates from Venezuela, Spain, and Taiwan. This is the first molecular detection of H. canis in dogs from Colombia.

Serosurvey of Ehrlichia canis and Hepatozoon canis infection in dogs in Yamaguchi Prefecture, Japan.

Antibodies to Ehrlichia canis and Hepatozoon canis in dogs at the Animal Hospital in Yamaguchi University were surveyed and potential risk factors for both pathogens were evaluated. Among 430 dogs examined, 20 (4.7%) and 18 (4.2%) dogs showed positive findings for E. canis and H. canis, respectively. Neither, sex nor age was associated with the seropositivity of either pathogen, but the positive rate in dogs kept outside was slightly higher than that in dogs kept inside for both pathogens. A higher seropositive reaction to E. canis and H. canis was observed in dogs that lived in certain cities and towns. Beagles, golden retrievers and pointers had higher seropositivity than other breeds in E. canis, whereas shibas, akitas, beagles, pointers and mongrels had higher positive rates than other breeds in H. canis.