Redescription of Hepatozoon felis (Apicomplexa: Hepatozoidae) based on phylogenetic analysis, tissue and blood form morphology, and possible transplacental transmission

Microscopy and molecular survey of Hepatozoon spp. in domestic cats and their ticks: First report of H. silvestris from Türkiye

Hepatozoonosis is a tick-borne infection caused by protozoan species of the Hepatozoon genus in the family Hepatozoidae. This study aimed to determine the presence and prevalence of Hepatozoon spp. in domestic cats and their ticks, to characterize the genotypes, to reveal phylogenetic relationships, and to assess the risk factors associated with infection. Blood samples were collected in EDTA tubes from 311 cats that were brought to the Veterinary Faculty, Animal Hospital for treatment or routine control purposes. Smears were prepared from the buffy coat and examined microscopically for the presence of Hepatozoon spp. gamonts. Ticks were collected during the clinical examination of the cats and the species were identified. Genomic DNA obtained from buffy coats and ticks were analyzed using PCR analyses targeting the 18S rRNA gene region of Hepatozoon spp. The results showed that Hepatozoon spp. gamonts in neutrophils were determined in five samples as 1.6 % (5/311). A total of 58 (18.64 %, 58/311) were positive for the PCR analyses. Twelve ticks were collected from the cats, and all were identified as Rhipicephalus turanicus. Hepatozoon spp. were found in seven (58.3 %) ticks by molecular analyses. Sequence analysis of the 18S rRNA gene region of 58 positive isolates revealed the presence of H. felis (n = 25, 43.1 %) and H. silvestris (n = 33, 56.9 %) species in cats and H. felis in Rh. turanicus (n = 7). This study also presents the first report of H. silvestris in domestic cats from Türkiye. Phylogenetic analyses showed that our H. felis isolates clustered in H. felis genotype I and our H. silvestris were stated in the same cluster with Italian isolates.

Geographical isolation and hyperendemicity of Hepatozoon felis: Epidemiological scenario in Skopelos, Greece, and phylogenetic analysis

Feline hepatozoonosis is a vector-borne disease caused by different species of the genus Hepatozoon, i.e. Hepatozoon felis, Hepatozoon silvestris and Hepatozoon canis. Knowledge on the biology, epidemiology and taxonomy of Hepatozoon spp. is still limited, despite the fact that the number of documented Hepatozoon spp. infections in domestic cats increased in recent years in different countries. This study was carried out to evaluate the prevalence and the genetic profile of Hepatozoon spp. in cats living on the island of Skopelos, Greece. Individual blood samples were collected from 54 owned cats and were subjected to Giemsa-stained blood smear examination to investigate the presence of Hepatozoon spp. gamonts and to a specific PCR protocol targeting the 18S rRNA gene of Hepatozoon. A total of 45 cats (83.3%) were found infected by Hepatozoon spp. by at least one of the methods applied. In particular, 43 (79.6%) of the cats were PCR-positive, and in 6 (11.1%) cats gamonts of Hepatozoon spp. were found in the blood smears. A total of 26 H. felis sequences were obtained and the presence of three undescribed single nucleotide polymorphisms were detected. The present results indicate that H. felis species complex may be hyperendemic in isolated/confined areas. In such contexts, geographical isolation may favor the origin of new genotypes or haplotypes or even new species.

Phylogenetic inferences based on distinct molecular markers reveals a novel Babesia (Babesia pantanalensis nov. sp.) and a Hepatozoon americanum-related genotype in crab-eating foxes (Cerdocyon thous)

Piroplasmids and Hepatozoon spp. Are apicomplexan protozoa that may cause disease in several canid species. The present study aimed to expand the knowledge on the diversity of piroplasmids and Hepatozoon in crab-eating foxes (Cerdocyon thous; n = 12) sampled in the Pantanal of Mato Grosso do Sul State, central-western Brazil. PCR assays based on the 18S rRNA were used as screening. Three (25%) and 11 (91.7%) were positive for piroplasmids and Hepatozoon spp., respectively. Co-infection was found in three C. thous. Phylogenetic analyses based on the near-complete 18S rRNA, cox-1 and hsp70 genes evidenced the occurrence of a novel of Babesia spp. (namely Babesia pantanalensis nov. sp.) closely related to Rangelia vitalii and Babesia sp. 'Coco'. This finding was supported by the genetic divergence analysis which showed (i) high divergence, ranging from 4.17 to 5.62% for 18 S rRNA, 6.16% for hps70 and 4.91-9.25% for cox-1 and (ii) the genotype network (which displayed sequences separated from the previously described Piroplasmida species by median vectors and several mutational events). Also, phylogenetic analysis based on the 18S rRNA gene of Hepatozoon spp. positioned the sequences obtained herein in a clade phylogenetically related to Hepatozoon sp. 'Curupira 2', Hepatozoon sp. detected in domestic and wild canids from Uruguay and Hepatozoon americanum. The present study described Babesia pantanalensis nov sp. and Hepatozoon closely related to H. americanum in crab-eating foxes from Brazil. Moreover, the coinfection by piroplasmids and Hepatozoon sp. for the first time in crab-eating foxes strongly suggesting that this wild canid species potentially acts as a bio-accumulate of hemoprotozoan in wild environment.

First identification of Cytauxzoon manul in Eurasian lynx (Lynx lynx) in northwestern China

BACKGROUND

Multiple species of the genera Cytauxzoon and Hepatozoon can infect wild felines, but the diversity of these and other apicomplexan parasites in Eurasian lynx is scarcely known. The aim of this study was to detect Cytauxzoon and Hepatozoon species with molecular methods in Eurasian lynxes and their ticks in northwestern China.

METHODS

DNA was extracted from the heart, liver, spleen, lung, and kidney samples of three Eurasian lynxes as well as from their five ixodid ticks. These DNA samples were screened with polymerase chain reactions (PCRs) for Cytauxzoon with the partial cytochrome b gene (CytB), cytochrome c oxidase subunit I gene (COI), and small subunit ribosomal RNA gene (18S rRNA), and Hepatozoon with three different fragments of small subunit ribosomal RNA gene (18S rRNA). PCR products were sequenced, aligned, and phylogenetically analyzed.

RESULTS

One adult female of Eurasian lynx (#1, adult female) was co-infected with Cytauxzoon manul and Hepatozoon felis genotype I, while an adult male lynx (#2) was infected with C. manul. Interestingly, H. felis genotype I was both detected in a male cub (#3) and two out of five infesting Hyalomma asiaticum ticks.

CONCLUSIONS

For the first time, Cytauxzoon manul is reported here from Eurasian lynx. In addition, H. felis has not been known to occur in this host species in China and Central Asia. Thus, the findings of this study extend our knowledge on the geographical distribution and host range of these haemoprotozoan parasites. Moreover, this is also the first evidence of C. manul and H. felis co-infection in Eurasian lynx.

Hepatozoon spp. in stray cats from the metropolitan area of Rio de Janeiro, Brazil

In the last few years, the number of studies on feline hepatozoonosis has increased, but our knowledge on the actual species of Hepatozoon and/or different genotypes affecting felines is still incipient. At least three species, namely Hepatozoon felis, H. canis, and H. silvestris, have been isolated from domestic cats in various countries. Additionally, there are indications that other species and genotypes may affect felines in given geographic areas. This study was carried out to investigate the occurrence of Hepatozoon spp. in cats from Niterói, a municipality within the metropolitan area of Rio de Janeiro, Brazil. Individual blood samples were collected from 28 cats enrolled in a spaying/castration program. DNA was extracted from all samples and subjected to sequencing specific for Hepatozoon spp. DNA of H. felis was found in 21/28 cats (75%), and four genetic polymorphisms never described thus far were detected. This is the first report of H. felis in cats living in the State of Rio de Janeiro, and the present data confirm that H. felis is a species complex encompassing different genotypes circulating within cat populations. Further studies are warranted to investigate whether different genotypes have different biology or pathogenicity for felids.

First report of Hepatozoon felis infection in a domestic cat (Felis catus) in Iran

A 6-year-old male domestic short-haired cat (Felis catus) was presented with weakness, anorexia, fever, icterus, a painful abdomen, ruffled hair and a tick infestation, and it had no prior surgery. Laboratory analysis revealed left-shifted neutrophils, thrombocytopenia, low albumin content and high serum bilirubin concentration as well as activities of hepatic enzymes including alanine aminotransferase and aspartate aminotransferase. Azotemia and increased serum levels of creatinine and urea were also recorded. In Giemsa-stained blood smear, Hepatozoon gamonts were observed within neutrophils. Species-specific polymerase chain reaction assay was used to amplify an approximately 590 bp fragment of 18S rRNA gene and confirmed Hepatozoon felis infection. The cat was treated with imidocarb dipropionate and doxycycline and recovered completely. Six-month follow-up showed no recurrence. This study reveals the presence of H. felis in Iran and it should be considered in differential diagnosis in febrile and icteric cats. To the authors' knowledge, this is the first description of H. felis infection in a cat in Iran.

Hepatozoon (Eucoccidiorida: Hepatozoidae) in wild mammals of the Americas: a systematic review

BACKGROUND

The study of parasites provides insight into intricate ecological relationships in ecosystem dynamics, food web structures, and evolution on multiple scales. Hepatozoon Eucoccidiorida: Hepatozoidae) is a genus of protozoan hemoparasites with heteroxenous life cycles that switch infections between vertebrates and blood-feeding invertebrates. The most comprehensive review of the genus was published 26 years ago, and currently there are no harmonized data on the epizootiology, diagnostics, genotyping methods, evolutionary relationships, and genetic diversity of Hepatozoon in the Americas.

METHODS

Here, we provide a comprehensive review based on the PRISMA method regarding Hepatozoon in wild mammals within the American continent, in order to generate a framework for future research.

RESULTS

11 out of the 35 countries of the Americas (31.4%) had data on Hepatozoon, with Carnivora and Rodentia orders having the most characterizations. Bats, ungulates, and shrews were the least affected groups. While Hepatozoon americanum, H. americanum-like, H. canis, H. didelphydis, H. felis, H. milleri, H. griseisciuri, and H. procyonis correspond to the identified species, a plethora of genospecies is pending for a formal description combining morphology and genetics. Most of the vectors of Hepatozoon in the Americas are unknown, but some flea, mite, and tick species have been confirmed. The detection of Hepatozoon has relied mostly on conventional polymerase chain reaction (PCR), and the implementation of specific real time PCR for the genus needs to be employed to improve its diagnosis in wild animals in the future. From a genetic perspective, the V4 region of the 18S rRNA gene has been widely sequenced for the identification of Hepatozoon in wild animals. However, mitochondrial and apicoplast markers should also be targeted to truly determine different species in the genus. A phylogenetic analysis of herein retrieved 18S ribosomal DNA (rDNA) sequences showed two main clades of Hepatozoon: Clade I associated with small mammals, birds, and herpetozoa, and Clade II associated with Carnivora. The topology of the tree is also reflected in the haplotype network.

CONCLUSIONS

Finally, our review emphasizes Hepatozoon as a potential disease agent in threatened wild mammals and the role of wild canids as spreaders of Hepatozoon infections in the Americas.

New insights on the phylogeography of Hepatozoon canis in Brazil

This study aimed to molecularly characterize the Hepatozoon spp. infecting domestic and wild dogs in Brazil. A total of 22 whole blood samples tested positive for Hepatozoon spp., and five samples were sequenced for the 18S rDNA gene from H. canis after PCR amplification with four primer sets. Phylogenetic analysis using Bayesian inference showed that the three H. canis isolates from domestic dogs were not monophyletic; however, they were more closely related to each other than to other H. canis sequences. The isolate from the hoary fox (Lycalopex vetulus) was phylogenetically more distant. Two haplotype networks were constructed, identifying 10 haplotypes of H. canis in Brazil, with H10 constituting the largest group. It contains nine isolates, including three from domestic dogs. The H5 haplotype grouped the sequence of L. vetulus with two additional sequences from hosts Tapirus terrestris and L. vetulus, representing the sole haplotype with wild hosts. Bayesian analysis suggested the possible existence of two genetic groups of H. canis in Brazil, indicating gene flow of this agent within the country. These findings contribute valuable insights for a more comprehensive understanding of the molecular diversity of Hepatozoon spp. in Brazil and may help in the development of effective control measures.

Phylogenetic analysis and haplotype networking of Hepatozoon felis infecting wild animals in Gir National Park, Gujarat, India

The present study was aimed to determine the phylogenetic relationship, haplotype network, and demographic dynamics of H. felis infecting the endangered Asiatic lions in Gir National Park, Gujarat, India, on the basis of partial 18S rRNA gene. The phylogenetic analysis based on the partial 18S rRNA gene sequences of H. felis exhibited the presence of two distinct genotypes of H. felis (HfG1 and HfG2) infecting the Indian wild felids, viz., the Asiatic lion, Royal Bengal tiger, and Indian leopard. The HfG1 and HfG2 genotypes exhibited 97.6-100% and 99.7-100%, and 96.9-98.7% nucleotide identity within and between themselves, respectively. The HfG1 genotype exhibited a higher genetic diversity as compared to HfG2. A total of 22 molecular signatures were identified in the 18S rRNA gene between these genotypes. Further, analysis of a total 67 sequences of H. felis (13 different host species from 13 countries of Africa, South America, Asia, and Europe) that were downloaded from GenBankTM, generated 30 haplotypes. Among all the haplotypes, Hap_17 (h=12) was the most frequent followed by Hap_12 (h=09) and Hap_4 (h=05). Out of 13 location-wise populations, India (h=12) shared the highest number of haplotypes followed by Japan (h=08), and the least number of haplotypes were found in Hungary (h=02). Population dynamics study involving neutrality tests and mismatch distribution, and genetic differentiation indices, revealed the presence of phylogeographic population structure and a constant population size indicating a uniform gene flow among the populations worldwide. In conclusion, a high genetic diversity along with the presence of two distinct genotypes of H. felis were observed on the basis of 18S rRNA gene sequence analysis.

Molecular survey on vector-borne pathogens in clinically healthy stray cats in Zaragoza (Spain)

BACKGROUND

In Europe, feline vector-borne infections are gaining importance because of the changing climate, expanding habitats of potential vectors and expanding pathogen reservoirs. The main objective of this study was to assess the prevalence of vector-borne pathogens (VBPs) in stray cats in Zaragoza, Spain, and to investigate potential risk factors for infection, including feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV).

METHODS

Blood samples from stray cats presented to the veterinary faculty in Zaragoza between February 2020 and 2022 were tested by polymerase chain reaction (PCR) for the presence of Anaplasma phagocytophilum, Anaplasma platys, Bartonella henselae, Ehrlichia canis, Rickettsia spp., haemotropic Mycoplasma spp., Hepatozoon spp., Leishmania infantum, piroplasms and microfilariae at the LABOKLIN laboratory. The cats were also tested for FeLV and FIV by PCR.

RESULTS

Nearly half of the cats (158/332, 47.6%) were positive for at least one VBP. Hepatozoon spp. were detected in 25.6%, haemotropic Mycoplasma spp. in 22.9%, B. henselae in 9.3% and L. infantum in 2.1% of the cats. Male sex had a statistically significant association with test results for haemotropic Mycoplasma spp. (odds ratio 1.38 [1.21;1.57]); regionality with Hepatozoon spp., B. henseale and FIV; and seasonality with Hepatozoon spp., haemotropic Mycoplasma spp., L. infantum and FeLV (P ≤ 0.05 each). A strong positive correlation was reported for the amount of rainfall and the number of cats that tested positive for Hepatozoon spp. (ρ = 753, P = 0.05). None of the cats tested positive for A. phagocytophilum, A. platys, E. canis, Rickettsia spp., piroplasms, or microfilariae. Co-infections with multiple VBPs were detected in 56 out of 332 cats (16.9%). Thirty-one of the 332 cats included in the study (9.3%) tested positive for FeLV (6.9%) and for FIV (3.6%). In 20/31 cats (64.5%) that tested positive for FeLV/FIV, coinfections with VBP were detected (P = 0.048, OR 2.15 [0.99; 4.64]).

CONCLUSIONS

VBPs were frequently detected in stray cats in Zaragoza. In particular, regionality and seasonality had a statistically significant association with PCR results for most VBPs included in the study.

Prevalence of gastro-intestinal and haemoparasitic infections among domestic cats of Kerala

The population of domesticated cats has drastically increased during the last decades. With the recently identified rise in cat population an upsurge in the parasitic infections associated with domestic cats is evident. A total of 122 domestic cats were screened for gastro-intestinal and haemoparasites. Screening for gastro-intestinal parasites revealed an overall prevalence of 19 per cent (23/122). Ancylostoma spp. was the major gastro-intestinal parasite noticed (61 per cent) followed by Toxocara cati (13.04 per cent), Isospora spp. (8.7 per cent), Diphyllobothrium latum (4.35 per cent) and mixed infection of these (13 per cent). Blood smear examination revealed Cytauxzoon spp. in three cats (2.46 per cent) and Babesia spp. in two cats (1.6 per cent). None of the cats were positive for gamonts of Hepatozoon spp. Molecular analysis revealed Hepatozoon spp. infection in seven cats (5.7 per cent), Cytauxzoon spp. in 29 cats (23.8 per cent) and Babesia spp. in two cats (1.6 per cent). Present study highlights the inevitability of molecular techniques in the identification of haemoparasites. Establishment of proper preventive measures are required to control parasitic infection among domestic cats.

Hepatozoon species infecting domestic cats from countries of the Mediterranean basin

Tick-borne diseases (TBDs) are caused by pathogens of human and veterinary concern representing a major public health issue worldwide. Although feline medicine has progressed much in the recent decades, data on feline TBDs (FeTBDs) remain scant. Therefore, this study aimed to assess the prevalence of apicomplexan parasite infections, associated risk factors and clinical-hematological abnormalities in domestic feline populations from countries of the Mediterranean basin. Blood and serum samples from cats (n = 600) living in France, Greece, Israel, Italy, Portugal and Spain were collected along with animal data (i.e., age, sex, breed, housing conditions and geographical origin), clinical signs and laboratory blood test parameters. Cats were grouped according to their age as kitten (up to one year), young (between one and six years), mature (between seven and ten years) and senior (older than ten years). Blood samples were tested for Hepatozoon spp. and piroplasmids by conventional PCR targeting 18S rRNA gene. The overall prevalence of Hepatozoon spp. infection was 14.5%, being significantly higher in cats from Greece (30%) and Portugal (23%), followed by Spain (15%), Israel (15%) and France (4%). Cats from Italy scored negative. Hepatozoon felis was identified in 86 animals, with three different sequence types and H. silvestris was detected in one shelter cat from Portugal. No piroplasmid DNA was amplified. The risk of Hepatozoon spp. infection was related to feline geographical provenience, housing condition and age. No statistical correlation was reported with any clinical signs, while increased alanine aminotransferase (ALT) activity was the only laboratory abnormality significantly associated (p = 0.03) with the infection. Data suggest a high circulation of H. felis, and only occasionally of H. silvestris, within domestic feline populations in the Mediterranean basin, mainly in shelter or free roaming and young cats with asymptomatic or subclinical infection.

Vector-Borne Pathogens in Stray Cats in Eastern Germany (Thuringia)

Bacterial, protozoal, and viral vector-borne pathogens (VBPs) can cause infections in cats. There is little information on feline VBP prevalence in Germany. Stray cats are frequently exposed to vectors but receive no veterinary care. The aim of this study was to determine the prevalence of selected VBPs in stray cats. EDTA blood and serum samples were taken from apparently healthy stray cats during a spay/neuter campaign in the federal state of Thuringia. Overall, 11/50 (22%) and 32/50 (64%) cats tested positive for at least one VBP by direct and indirect detection methods, respectively. PCR testing of EDTA blood detected hemotropic Mycoplasma spp. in 12% of cats, Hepatozoon spp. in 10%, and Anaplasma phagocytophilum in 4%. PCR testing for Rickettsia spp. and piroplasms was negative. IFAT on serum samples showed 46% of cats had detectable antibodies for Bartonella spp., 30% for Rickettsia spp., and 16% for A. phagocytophilum. The cats were additionally tested for feline coronavirus, FIV, and FeLV to identify potential risk factors for pathogen contact and/or infections. No correlation between FIV and FeLV status and VBP positivity was detected. Anaplasma phagocytophilum, Rickettsia spp., and Bartonella spp. have zoonotic potential, and surveillance is recommended in the context of the One Health approach.

Molecular survey of Cytauxzoon spp. and Hepatozoon spp. in felids using a novel real-time PCR approach

Tick-transmitted apicomplexans of the genera Cytauxzoon and Hepatozoon affect a wide range of felids worldwide, but little is known about them. Recently, several studies addressed the species circulating in Europe, their distribution, and their hosts. Molecular assays are the method of choice for their detection. Unfortunately, conventional PCRs already described are time- and cost-consuming and specific for either Hepatozoon or Cytauxzoon detection. This study was developed to evaluate (i) the occurrence of Cytauxzoon and Hepatozoon in felids using a fast and cost-saving real-time PCR capable of detecting both protozoa simultaneously, (ii) the distribution of Cytauxzoon and Hepatozoon species in north-eastern Italy, and (iii) the involvement of other susceptible felid hosts in the same area. An SYBR^® Green-based real-time PCR with primers targeting the 18S-rRNA was validated and applied to 237 felid samples, i.e., whole blood from 206 domestic cats and 12 captive exotic felids, and tissues from 19 wildcats. Positive results were obtained by melting temperature curve analysis due to the specific melting peak (i.e., 81°C Cytauxzoon spp.; 78-78.5°C Hepatozoon spp.). Positive samples were subjected to conventional PCR, followed by sequencing for species identification. Phylogenetic analyses were performed to assess relatedness among European isolates. Data on domestic cats (age class, sex, origin, management, and lifestyle) were recorded, and statistical analyses were performed to identify potential risk factors. A total of 31 (15%) domestic cats were positive for Hepatozoon spp. (i.e., 12 for H. felis, 19 for H. silvestris), while six (2.9%) for C. europaeus. The prevalence of Hepatozoon felis was significantly (p < 0.05) higher in domestic cats, while H. silvestris was higher in strays and animals from the Eastern region (i.e., Friuli-Venezia Giulia). Cytauxzoon europaeus was detected only in stray cats from Friuli-Venezia Giulia (province of Trieste). Among captive felids, one tiger was infected with H. felis and another with H. silvestris; eight out of 19 (42%) wildcats were positive for Hepatozoon spp. (i.e., six with H. felis, two with H. silvestris) and four out of 19 (21%) for Cytauxzoon europaeus. Outdoor lifestyle and origin (i.e., Friuli-Venezia Giulia region) were the most relevant risk factors for H. silvestris and C. europeus infections. Conversely, H. felis was most frequently isolated from domestic cats, suggesting different modes of transmission.

Hepatozoon silvestris: an emerging feline vector-borne pathogen in Europe?

Hepatozoon silvestris (Adeleorina: Hepatozoidae) is a recently described agent of feline hepatozoonosis. Although possibly emerging in Europe, this apicomplexan parasite is still largely unknown. Here, we provide insight into our current knowledge of the parasite's distribution, biology, and pathogenesis of the associated disease.

Genetic diversity in Babesia bovis from southern Africa and estimation of B. bovis infection levels in cattle using an optimised quantitative PCR assay

Babesia bovis is a causal agent of bovine babesiosis, a disease which leads to mortality and morbidity and impacts the cattle industry worldwide. We amplified, cloned and sequenced the B. bovis merozoite surface antigen-2b (msa-2b) gene (_∼940 bp) and the near full-length 18S rRNA gene (_∼1600 bp) from cattle samples from South Africa and Mozambique to determine sequence variation between B. bovis parasites in the region. A TaqMan quantitative real-time PCR (qPCR) assay (18S rRNA gene) was optimised for the detection of B. bovis and estimation of parasitaemia in field samples from cattle from southern Africa. Phylogenetic analysis grouped the Msa-2b sequences in six clades and these were 59.7 to 99.6% identical to reference sequences. Sequence variation amongst B. bovis 18S rRNA sequences was found at 2 to 36 positions, and the sequences were 97 to 99% identical to published sequences. Mismatches between the B. bovis 18S rRNA sequences and a previously published qPCR forward primer (BoF) were observed; therefore, we developed a new forward primer (BoF2), and optimised the qPCR assay. Six 10-fold dilution series of B. bovis infected erythrocytes (2 × 10⁸ to 2 × 10³ infected red blood cells [iRBC]/ml) were analysed in triplicate in each of six separate qPCR runs, to determine the efficiency of the assay. The qPCR assay amplified the B. bovis 18S rRNA gene with 92.0 to 94.9% efficiency. The detection limit of the qPCR assay was approximately 6 iRBCs/μl. The performance of the optimised assay to diagnose B. bovis in field samples was assessed by testing DNA from 222 field samples of cattle from South Africa and Mozambique using three methods: the optimised qPCR assay, the reverse line blot (RLB) hybridisation assay, and the previously published qPCR assay. The detection rate of B. bovis using the optimised qPCR assay (31.1%, 69/222) was significantly higher (p<0.001) than both that using RLB (20.7%, 46/222) and the previously published qPCR assay (5.4%; 12/222). The B. bovis parasitaemia in samples from infected cattle ranged from 6 iRBCs/μl to 101,852 iRBCs/μl of blood. Our study revealed marked sequence variation between B. bovis parasites from southern Africa. The optimised qPCR assay will be useful in epidemiological studies and clinical diagnosis of B. bovis in southern Africa, and can be used to determine parasitaemia and potential carrier status in cattle populations, which is essential in the control of babesiosis.

Apicomplexan haemoparasites in domestic cats in Romania

BACKGROUND

Apicomplexan haemoparasites are protozoans that infect a variety of domestic and wild animal species, as well as humans. Data regarding haemoprotozoans in domestic cats are limited; therefore, the aim of this study was to assess the occurrence of Babesia spp., Cytauxzoon spp., and Hepatozoon spp. in domestic cats in Romania using molecular tools.

METHODS

Blood samples from 371 domestic cats were screened for the presence of piroplasmids. All samples that yielded a visible band in agarose gels were subsequently tested by specific assays targeting the 18S rDNA of Babesia spp., Cytauxzoon spp., and Hepatozoon spp. Moreover, nested PCR assays targeting mitochondrial genes of Babesia spp. were used for screening of all Babesia spp. 18S rDNA-positive samples.

RESULTS

From the total number of sampled cats, 19.4% were positive in the PCR assay targeting piroplasmids. Babesia spp. were identified in 15.1% of cats, while 0.5% were positive for Hepatozoon spp. Molecular analyses confirmed the presence of Babesia canis. No samples were positive for Cytauxzoon spp.

CONCLUSIONS

The high infection rates of domestic cats with Babesia spp. and the need for species differentiation highlight the importance of mitochondrial genes as targets for molecular protocols.

Diversity of Hepatozoon species in wild mammals and ticks in Europe

BACKGROUND

Hepatozoon spp. are tick-borne parasites causing subclinical to clinical disease in wild and domestic animals. Aim of this study was to determine Hepatozoon prevalence and species distribution among wild mammals and ticks in Europe.

METHODS

Samples of wild mammals and ticks, originating from Austria, Bosnia and Herzegovina, Croatia, Belgium and the Netherlands, were tested with PCR to amplify a ~ 670-bp fragment of the small subunit ribosomal RNA gene.

RESULTS

Of the 2801 mammal samples that were used for this study, 370 (13.2%) tested positive. Hepatozoon canis was detected in samples of 178 animals (3 Artiodactyla, 173 Carnivora, 1 Eulipotyphia, 1 Lagomorpha), H. martis in 125 (3 Artiodactyla, 122 Carnivora), H. sciuri in 13 (all Rodentia), Hepatozoon sp. in 47 (among which Hepatozoon sp. Vole isolate, all Rodentia) and H. ayorgbor in 4 (all Rodentia). Regarding origin, 2.9% (6/208) tested positive from Austria, 2.8% (1/36) from Bosnia and Herzegovina, 14.6% (173/1186) from Croatia and 13.9% (190/1371) from Belgium/the Netherlands. Of the 754 ticks collected, 0.0% (0/35) Hyalomma sp., 16.0% (4/25) Dermacentor spp., 0.0% (0/23) Haemaphysalis spp., 5.3% (24/50) Ixodes and 1.4% (3/221) Rhipicephalus spp. tested positive for Hepatozoon (4.2%; 32/754), most often H. canis (n = 22).

CONCLUSIONS

Hepatozoon canis is most present in mammals (especially in Carnivora such as gray wolves and golden jackals) and ticks, followed by H. martis, which was found merely in stone martens and pine martens. None of the rodent-associated Hepatozoon spp. were detected in the ticks, suggesting the possible implication of other arthropod species or non-vectorial routes in the transmission cycle of the hemoprotozoans in rodents. Our findings of H. canis in ticks other than R. sanguineus add to the observation that other ticks are also involved in the life cycle of Hepatozoon. Now that presence of Hepatozoon has been demonstrated in red foxes, gray wolves, mustelids and rodents from the Netherlands and/or Belgium, veterinary clinicians should be aware of the possibility of spill-over to domestic animals, such as dogs.

Wild Mesocarnivores as Reservoirs of Endoparasites Causing Important Zoonoses and Emerging Bridging Infections across Europe

Mesocarnivores are small- or mid-sized carnivore species that display a variety of ecologies and behaviours. In Europe, wild mesocarnivores are represented by the red fox (Vulpes vulpes), the golden jackal (Canis aureus), the European wildcat (Felis silvestris), the Mustelidae of the genera Meles, Martes, Mustela, Lutra, the invasive species of raccoon dog (Nyctereutes procyonoides), raccoons (Procyon lotor), and American mink (Neogale vison). These abundant animals thrive in various habitats and often develop their activity close to human settlements. Thus, they may play an important role in the introduction, maintenance, and transmission of major parasitic zoonoses and promote bridging infections with domestic animals. Against this background, this article reports and discusses some of the most important endoparasites of wild mesocarnivores living in Europe, on the basis of their actual role as reservoirs, spreaders, or sentinels. The data derived from epizootiological studies in different European countries, and the proven or speculated implications of the detected endoparasites in human and domestic animals' health, are discussed. Through older and recent literature review, the state-of-the-art knowledge on the occurrence and prevalence of the parasites under consideration is presented, showing further, warranted investigations and the need for surveillance and vigilance.

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 analysis of blood-associated pathogens in European wildcats (Felis silvestris silvestris) from Germany

European wildcats (Felis silvestris silvestris) have not been investigated in large numbers for blood-associated pathogens in Germany, because wildcats, being a protected species, may not be hunted, and the collection of samples is therefore difficult. Thus, spleen tissue and whole blood from 96 wildcats from Germany found as roadkill or dead from other causes in the years 1998–2020 were examined for the prevalence of blood associated pathogens using molecular genetic tools. PCR was used to screen for haemotrophic Mycoplasma spp., Hepatozoon spp., Cytauxzoon spp., Bartonella spp., Filarioidea, Anaplasmataceae, and Rickettsiales, and positive samples were subsequently sequenced. Phylogenetic analyses were performed for Mycoplasma spp. and Hepatozoon spp. by calculating phylogenetic trees and DNA haplotype networks. The following pathogens were found: Candidatus Mycoplasma haematominutum (7/96), Mycoplasma ovis (1/96), Hepatozoon silvestris (34/96), Hepatozoon felis (6/96), Cytauxzoon europaeus (45/96), and Bartonella spp. (3/96). This study elucidates the prevalence of blood-associated pathogens in wildcats from Germany.

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European wildcats from Germany carry different blood-associated pathogens.

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Pathogens can also affect domestic cats.

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Transmision by vectors or other transmisison routes are possible.

First autochthonous clinical case of Hepatozoon silvestris in a domestic cat in Italy with unusual presentation

Hepatozoon spp. is the causative agent of a vector-borne parasitic disease in many animal species. In felids, Hepatozoon felis, Hepatozoon canis and Hepatozoon silvestris have been molecularly isolated. Hepatozoonosis usually causes asymptomatic infections in domestic cats, but clinical cases have recently been reported in Europe. We describe the first Italian case of hepatozoonosis in a cat with an unusual presentation. An 11-year-old neutered European shorthair cat was urgently hospitalized for intestinal intussusception. Hematology, biochemistry, FIV-FeLV tests, blood smears and molecular investigation targeting the 18S rRNA gene of Hepatozoon spp. were performed on blood samples; in addition, histological and molecular investigations were performed to analyze surgical samples to identify Hepatozoon infection. Hepatozoon gamonts were detected in granulocytes in the blood smear, and Hepatozoon spp. DNA was confirmed by PCR on blood. The intussusception was caused by a sessile endoluminal nodule that was surgically removed. Histologically, many elements referring to parasitic tissue forms were identified in the intestinal cells, and then the specimens were molecularly confirmed to harbor H. silvestris. This is the first description of symptomatic hepatozoonosis in a domestic cat in Italy. Hepatozoon silvestris has been described in wild felids, which are usually resilient to the infection, whereas the domestic cat seems to be more susceptible. Indeed, H. silvestris in cats usually presents tropism for skeletal muscle and myocardium with subsequent clinical manifestations. This is the first description of a domestic cat with H. silvestris localized in the intestinal epithelium and associated with intussusception.

Description of a novel Babesia sp. genotype from a naturally infected Eurasian lynx (Lynx lynx) in Anatolia, Turkey, with remarks on its morphology and phylogenetic relation to other piroplasmid species

There are very limited data on Babesia species infecting lynx species worldwide, and almost nothing is known about babesias in the Eurasian lynx, the most widely distributed wild feline species in the Palearctic geography. This study describes a novel Babesia sp. genotype in a free-living Eurasian lynx in Turkey, named tentatively as 'Babesia sp. lynx', and its integrated genetic and morphological features. Phylogenetic analyses of piroplasmids with the novel Babesia sp. genotype in the current study indicated that this genotype falls into the 'carnivore clade A' of Babesia sensu stricto (true babesias), at the level of different genes (mainly 18S rRNA, ITS1, ITS2, and cyt b) and is monophyletic with the Babesia sp. Ankara genotype, previously observed in Turkey. Additionally, the constructed phylogenetic trees showed that the Babesia sp. lynx genotype infecting the Eurasian lynx is closely related to certain domestic and wild carnivore babesias, mainly Babesia rossi, Babesia presentii, and Babesia pisicii, at the level of different genes. This study also genetically barcoded the lynx infected with the Babesia sp. lynx and Haemaphysalis erinacei, and specimens collected from the animal revealed significant genetic variations between the sample Ha. erinacei and Babesia sp. Ankara-related Ha. erinacei that persists with sympatric populations in Central Anatolia. The lynx infected with the Babesia sp. lynx genotype was also found to be coinfected with Hepatozoon felis, an adeleorinid tick-borne protozoan parasite infecting wild and domestic felids, confirming for the first time its presence in a lynx species. Therefore, this study is the first to describe a potential novel Babesia sp. using its both morphological and phylogenetic characteristics in a lynx species. Adding the Babesia sp. lynx genotype to the phylogeny of feline piroplasmids significantly expands our knowledge of feline babesias in the Palearctic geography and their putative coevolution with their vertebrate hosts.

Molecular detection of Hepatozoon species infections in domestic cats living in Germany

OBJECTIVES

Three species of protozoal Hepatozoon species (H felis, H canis and H silvestris) are known to infect cats in Europe. The objective of this study was to determine the prevalence of Hepatozoon species in samples from cats living in Germany that were submitted to a veterinary laboratory.

METHODS

The study included cats tested for Hepatozoon species by PCR between 2007 and 2020 by the Laboklin laboratory. Travel history and haematological results were documented for cats with positive test results. From 2018 onwards, a partial 18S rRNA Hepatozoon gene fragment was sequenced from cats with positive PCR results.

RESULTS

Sixty-four of 931 cats (7%) tested positive for Hepatozoon species. Sex and age did not have a statistically significant impact. Sequencing was carried out for 16 samples and revealed H felis in all cases. All cats with positive test results and a relevant travel history had been imported from the Mediterranean or south-eastern Europe. There were no autochthonous infections with Hepatozoon species. Leukocytosis, haemoconcentration and anaemia were the most common haematological abnormalities.

CONCLUSIONS AND RELEVANCE

Although infections with Hepatozoon species in cats are usually subclinical, it may be useful to screen cats imported from the Mediterranean and south-eastern Europe for these pathogens to prevent local transmission cycles. There was no evidence of autochthonous infections in Germany; however, further investigations regarding a possible transmission of Hepatozoon species from infected cats to blood-feeding arthropods in Germany may be of interest. To avoid potential spread of the pathogens, ectoparasite prophylaxis is advisable.

Large-scale survey for canine vector-borne parasites in free-ranging dogs and foxes from six diverse bioclimatic regions of Chile

Chile is a large country with a marked range of climate conditions that make it an ideal scenario for the study of vector-borne parasites (VBPs); however, knowledge about their distribution is limited to a few confined areas of this country. The presence of Hepatozoon spp., piroplasmids, Leishmania spp. and filarioids was investigated through molecular and serological methods in blood and serum samples of 764 free-ranging rural dogs, 154 Andean foxes (Lycalopex culpaeus), and 91 South American grey foxes (Lycalopex griseus) from six bioclimatic regions across Chile. Hepatozoon spp. DNA was exclusively detected in foxes (43% prevalence), including sequences closely related to Hepatozoon felis (24.1%; only Andean foxes), Hepatozoon americanum (16.2%; only grey foxes), and Hepatozoon canis (1.25%; in one grey fox). Risk factor assessment identified a higher probability of Hepatozoon infection in juvenile foxes. DNA of piroplasmids was detected in 0.7% of dogs (Babesia vogeli) but in no fox, whilst antibodies against Babesia sp. were detected in 24% of the dogs and 25% of the foxes, suggesting a wider circulation of canine piroplasmids than previously believed. A positive association between the presence of antibodies against Babesia and high Rhipicephalus sanguineus sensu lato burden was observed in dogs. Leishmania spp. DNA and antibodies were detected in 0.8% and 4.4% of the dogs, respectively. Acanthocheilonema reconditum was the only blood nematode detected (1.5% of the dogs and no fox). Differences in prevalence among bioregions were observed for some of the VBPs. These results expand our knowledge about the occurrence of vector-borne parasites in Chile, some of which are firstly reported herein. This information will facilitate the diagnosis of vector-borne diseases in domestic dogs and improve the control measures for both domestic and wild canids.

Occurrence and Molecular Identification of Hemoparasites in Wild Mammals Kept in Rehabilitation Centers in Brazil

PURPOSE

Hepatozoonosis and piroplasmosis are diseases caused by apicomplexan protozoa that affect different types of animals, including mammals. The present study aimed to evaluate the occurrence of Hepatozoon spp. and piroplasms in wild mammals kept in captivity in rehabilitation centers in the states of Minas Gerais and Goiás, Brazil.

METHODS

For this, blood samples from 152 animals were collected and analyzed by conventional optical microscopy and polymerase chain reaction (PCR). In addition, positive PCR samples were submitted to sequencing for molecular characterization of the specimens found.

RESULTS

Microscopic analysis revealed 53 of the 152 animals (28.3%) parasitized by piroplasms. No Hepatozoon sp. was observed. On the other hand, using the primers HepF300/HepR900 and Piro1F/Piro5R, both amplifying fragments of the 18S rDNA gene, eight animals (5.2%) were positive for Hepatozoon spp. and 40 (26.3%) for piroplasms. From the sequencing of the positive samples Hepatozoon canis, Hepatozoon felis, Theileria cervi, Theileria equi and Cytauxzoon felis were identified. In addition to the aforementioned hemoparasites, some animals were found parasitized by microfilaria. Such data ratify the presence of hemoparasites in captive wild animals, and are unprecedented in the two geographical regions covered by the present study. 19.7% of mammals harbored ectoparasites of the genera Amblyomma and Rhipicephalus.

CONCLUSION

Wild mammals are infected by several pathogens that can also infect domestic animals, some of them potentially zoonotic which can directly contribute to mortality and species reduction. Therefore, a deep understanding of the parasites, the hosts and the diseases is extremely necessary so that prevention, control and treatment measures are effectively applied.

Canine and Feline Parasitology: Analogies, Differences, and Relevance for Human Health

Cats and dogs are treated as family members by most pet owners. Therefore, a high quality of veterinary care and preventive medicine is imperative for animal health and welfare and for the protection of humans from zoonotic pathogens. There is a general perception of cats being treated as "small dogs," especially in the field of clinical parasitology. As a result, several important differences between the two animal species are not taken into proper consideration and are often overlooked. Dogs and cats are profoundly different under evolutionary, biological, ethological, behavioral, and immunological standpoints. These differences impact clinical features, diagnosis, and control of canine and feline parasites and transmission risk for humans. This review outlines the most common parasitoses and vector-borne diseases of dogs and cats, with a focus on major convergences and divergences, and discusses parasites that have (i) evolved based on different preys for dogs and cats, (ii) adapted due to different immunological or behavioral animal profiles, and (iii) developed more similarities than differences in canine and feline infections and associated diseases. Differences, similarities, and peculiarities of canine and feline parasitology are herein reviewed in three macrosections: (i) carnivorism, vegetarianism, anatomy, genetics, and parasites, (ii) evolutionary adaptation of nematodes, including veterinary reconsideration and zoonotic importance, and (iii) behavior and immune system driving ectoparasites and transmitted diseases. Emphasis is given to provide further steps toward a more accurate evaluation of canine and feline parasitology in a changing world in terms of public health relevance and One Health approach.

Cytauxzoon sp. and Hepatozoon spp. in Domestic Cats: A Preliminary Study in North-Eastern Italy

Knowledge on the presence of Cytauxzoon sp. and Hepatozoon spp. in Italy is scant and mostly limited to a few areas of Northern and Southern regions, respectively. The present study updated the current epidemiological scenario by investigating the occurrence of these protozoa in domestic cats from three broad regions of North-Eastern Italy. Blood samples from cats at risk of vector-borne diseases were processed by PCR to detect Cytauxzoon and Hepatozoon DNA. Blood smears were observed for haemoparasite inclusions. The influence of cat individual data (e.g., provenance, management, indoor/outdoor lifestyle) on the prevalence of haemoprotozoan infections was statistically evaluated. Among 158 cats, Cytauxzoon and Hepatozoon DNA were detected in 6 (3.8%) and 26 (16.5%) animals, respectively. No Hepatozoon gamonts were detected in blood smears, whereas all Cytauxzoon PCR-positive samples were microscopically positive, though with low levels of parasitaemia. Two species of Hepatozoon were identified, Hepatozoon felis (n = 10) and Hepatozoon silvestris (n = 16). Hepatozoon silvestris prevalence values were significantly (p < 0.05) higher in the region Friuli Venezia Giulia and in stray cats. Cytauxzoon sp. was detected in 6/39 (15.4%) stray cats from Friuli Venezia Giulia (Trieste province). These data add new information on the occurrence of these neglected protozoa in domestic cats' populations.

An Hepatozoon americanum-like protozoan in crab-eating (Cerdocyon thous) and grey pampean (Lycalopex gymnocercus) foxes from Uruguay

In South America, apicomplexan parasites of the genus Hepatozoon have been sporadically detected in mammals. Previous studies in wild canids from Brazil and Argentina demonstrated infections by species genetically related to Hepatozoon americanum. The aim of the present work was to detect the presence of Hepatozoon in road-killed foxes encountered in Uruguayan highways. Blood samples from 45 crab-eating (Cerdocyon thous) and 32 grey pampean (Lycalopex gymnocercus) foxes were analyzed by PCR for Hepatozoon 18S rRNA gene. Eight foxes (10.4%) were found to be infected with an H. americanum-like protozoan, an Hepatozoon closely related to H. americanum. Bayesian and maximum-likelihood phylogenetic analyses revealed that the sequences obtained in this study cluster with H. americanum from the United States, and with an H. americanum-like species from dog and foxes from Brazil and Argentina. In the Unites States, H. americanum causes severe disease in dogs. In addition to this, an increasing habitat overlap between dogs and foxes makes the presence of H. americanum-like protozoan in foxes acquires veterinary relevance. This work represents the first report of L. gymnocercus infected with an H. americanum-like protozoan, and of wild canids infected with Hepatozoon in Uruguay.

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.

Lack of evidence of vertical transmission of Karyolysus blood parasites in Iberian green lizards (Lacerta schreiberi)

To understand the spread of parasite and the persistence of infection in an ecological environment, it is essential to investigate their transmission possibilities. Vertical transmission of pathogens from mother to offspring is a fundamental opportunity, notwithstanding a relatively under-researched topic, especially in wildlife animals. We studied whether there is vertical transmission of a haemogregarinid blood parasite of Iberian green lizard (Lacerta schreiberi). To study infection of mothers, embryos and freshly hatched juveniles, their blood smears and molecular analyses of their tail tissue were used. Examining blood smears, seventy-one percent of females were found to be infected, but molecular analyses of all mothers showed positive results for the blood parasite. Based on molecular data the parasite was identified as a Karyolysus species. In contrast, no parasite was found in the blood smears of the freshly hatched juveniles, and we could not detect Karyolysus in the embryos or tail tissue of offspring using molecular methods either. Based on our results, vertical transmission of Karyolysus blood parasites is unlikely in the Iberian green lizard.

Protozoan and Microbial Pathogens of House Cats in the Province of Tekirdag in Western Turkey

Domestic felines’ re-emerging infectious and neglected zoonotic diseases are a significant focus of global “One Health” efforts. This study aimed to rapidly diagnose 14 pathogens, including zoonoses by using PCR primers in 167 client-owned symptomatic cats, routinely accepted to the Veterinary Clinics of Tekirdag. The prevalence of pathogens investigated were as follows: Babesia canis canis (24%), Babesia microti (2.4%), Hepatozoon felis (10.8%), Cytauxzoon felis (6.6%), Bartonella henselae (40.1%), Anaplasma platys (30.5%), Anaplasma phagocytophilum (7.2%), Rickettsia felis (26.3%), Borrelia burgdorferi (21%), and hemotropic Mycoplasma sp. (11.4%). There was a significant difference between the prevalence of the pathogens (χ² = 152.26, df = 9, p < 0.001). There was also a statistical difference between the gender of the cats in terms of the prevalence of all pathogens considered together (χ² = 4.80, df = 1, p = 0.028), where the female cats showed a higher prevalence. This was not the case for the different age groups (χ² = 2.92, df = 1, p = 0.088). The lowest infection was observed for B. microti (p < 0.001), while the highest infection was observed for B. henselae (p < 0.01). Leishmania donovani, Plasmodium spp., Ehrlichia chaffeensis, and Neoehrlichia mikurensis PCR test results were negative in all samples. In conclusion, house cats of Tekirdag are apparently highly susceptible to some neglected zoonoses important for “One Health”, and their prevalence in the region is most probably underestimated. Hence, applying PCR tests to assist fast clinic diagnosis in routine, may be an efficient option to protect the public as well as the cats from severe diseases.

Retrospective evaluation of vector-borne pathogens in cats living in Germany (2012-2020)

BACKGROUND

Blood-feeding arthropods can transmit parasitic, bacterial, or viral pathogens to domestic animals and wildlife. Vector-borne infections are gaining significance because of increasing travel and import of pets from abroad as well as the changing climate in Europe. The main objective of this study was to assess the percentage of cats with positive test results for selected vector-borne pathogens in Germany and explore any possible association of such results with time spent abroad.

METHODS

This retrospective study included test results from cats included in the "Feline Travel Profile" established by the LABOKLIN laboratory at the request of veterinarians in Germany between April 2012 and March 2020. This diagnostic panel includes the direct detection of Hepatozoon spp. and Dirofilaria spp. via PCR as well as indirect detection assays (IFAT) for Ehrlichia spp. and Leishmania spp. The panel was expanded to include an IFAT for Rickettsia spp. from July 2015 onwards.

RESULTS

A total of 624 cats were tested using the "Feline Travel Profile." Serum for indirect detection assays was available for all 624 cats; EDTA samples for direct detection methods were available from 618 cats. Positive test results were as follows: Ehrlichia spp. IFAT 73 out of 624 (12%), Leishmania spp. IFAT 22 out of 624 (4%), Hepatozoon spp. PCR 53 out of 618 (9%), Dirofilaria spp. PCR 1 out of 618 cats (0.2%), and Rickettsia spp. IFAT 52 out of 467 cats (11%) tested from July 2015 onwards. Three cats had positive test results for more than one pathogen before 2015. After testing for Rickettsia spp. was included in 2015, 19 cats had positive test results for more than one pathogen (Rickettsia spp. were involved in 14 out of these 19 cats).

CONCLUSIONS

At least one pathogen could be detected in 175 out of 624 cats (28%) via indirect and/or direct detection methods. Four percent had positive test results for more than one pathogen. These data emphasize the importance of considering the above-mentioned vector-borne infections as potential differential diagnoses in clinically symptomatic cats.

Molecular Characterization of Hemoparasites and Hemoplasmas Infecting Domestic Cats of Southern India

In the present study, 111 blood samples were collected from apparently healthy cats belonging to four districts of Kerala, southern India, and they were investigated for the presence of hemoparasites and hemoplasmas by light microscopic examination and polymerase chain reaction (PCR). The microscopic examination of the Giemsa-stained blood smears did not reveal any parasites/organisms. However, PCR followed by nucleotide sequencing could detect 10 (9.01%) out of 111 samples infected with Hepatozoon felis, 3 (2.70%) with Cytauxzoon spp., and 10 (9.01%) with Mycoplasma spp. None of the samples revealed amplicons specific for the Babesia spp. and Trypanosoma evansi. The phylogenetic analysis of 18S ribosomal RNA (rRNA) gene sequences of H. felis revealed the existence of two different populations of H. felis circulating in the blood of infected cats. The phylogenetic tree was constructed based on 18S rRNA gene sequences of Cytauxzoon spp. and revealed that these isolates formed a distinct clade and do not cluster with any of the isolates from other countries. Among the 10 samples positive for Mycoplasma spp. infections, 7 were detected positive for Candidatus Mycoplasma haemominutum, two for Mycoplasma haemofelis, and one for Candidatus Mycoplasma turicensis. Phylogenetic analysis of 16S rRNA gene sequences of Mycoplasma spp. showed no distinct geographical grouping of the sequences. The sequences of M. haemofelis, Candidatus M. haemominutum, and Candidatus M. turicensis identified in the study clustered along with their respective isolates from around the world. To the best of our knowledge, this study forms the first report of molecular detection of Cytauxzoon spp. and Candidatus M. turicensis in cats from India.

Haemogregarines and Criteria for Identification

Simple Summary

Taxonomic classification of haemogregarines belonging to Apicomplexa can become difficult when the information about the life cycle stages is not available. Using a self-reporting, we record different haemogregarine species infecting various animal categories and exploring the most systematic features for each life cycle stage. The keystone in the classification of any species of haemogregarines is related to the sporogonic cycle more than other stages of schizogony and gamogony. Molecular approaches are excellent tools that enabled the identification of apicomplexan parasites by clarifying their evolutionary relationships.

Abstract

Apicomplexa is a phylum that includes all parasitic protozoa sharing unique ultrastructural features. Haemogregarines are sophisticated apicomplexan blood parasites with an obligatory heteroxenous life cycle and haplohomophasic alternation of generations. Haemogregarines are common blood parasites of fish, amphibians, lizards, snakes, turtles, tortoises, crocodilians, birds, and mammals. Haemogregarine ultrastructure has been so far examined only for stages from the vertebrate host. PCR-based assays and the sequencing of the 18S rRNA gene are helpful methods to further characterize this parasite group. The proper classification for the haemogregarine complex is available with the criteria of generic and unique diagnosis of these parasites.

Arthropod-Borne Pathogens in Stray Cats from Northern Italy: A Serological and Molecular Survey

Cats may be affected by a wide range of arthropod-borne pathogens (ABPs) of medical and veterinary interest. Between February 2018 and October 2019, 85 blood samples were collected from stray cats from the Emilia Romagna region (northern Italy). Ticks (n = 28) on the examined cats were also collected. Serological and molecular methods were applied to search for infection by Anaplasma phagocytophilum, Bartonella henselae, Coxiella burnetii, Ehrlichia canis, Leishmania spp., Babesia spp., Hepatozoon spp., and Cytauxzoon spp. A total of 71 sera (83.5%) had antibodies to at least one investigated pathogen: 39 (45.9%) were positive for B. henselae, 32 (37.6%) positive for C. burnetii, 12 (14.1%) positive for E. canis, four (4.7%) positive for A. phagocytophilum, and two (2.4%) positive for Leishmania spp. A total of 47 (55.3%) DNA samples were positive by PCR for at least one investigated pathogen: 25 (29.4%) were positive for C. burnetii, 23 (27.1%) positive for B. henselae, two (2.4%) positive for E. canis, five (5.9%) positive for Leishmania spp., and two (2.4%) positive for Cytauxzoon spp. Coinfections were observed in 21 cats (24.7%). No positivity was found for A. phagocytophilum, Babesia spp., or Hepatozoon spp. All ticks were negative. A widespread presence of ABPs in the investigated area of northern Italy was shown. Accurate information on their prevalence may be relevant for feline veterinary medicine, as well as from a One Health perspective.

First record of Hepatozoon spp. in domestic cats in Greece

Feline hepatozoonosis is an emerging disease of domestic and wild felids though there is limited knowledge of this infection, e.g. regarding geographical distribution and parasite species involved. The present study evaluated microscopically and molecularly the occurrence of Hepatozoon spp. in domestic cats from insular (Crete, Mykonos and Skopelos) and continental (prefectures of Attica and Thessaloniki) Greece. Out of 282 cats examined, 72 (25.5 %) scored positive by PCR for Hepatozoon spp. and of them, 9 (12.5 %) showed gamonts on the blood smear microscopic examination. Sequences obtained from 35 of the amplicons proved the presence of two haplotypes of Hepatozoon felis. One, herein called H1 (34/35 amplicons) resulted 100 % identical with H. felis from Italy and isolates from other continents, and ∼98 % similar with a H. felis isolate causing severe clinical signs in Austria. The haplotype H2, found in a cat in Skopelos, had ∼94 % identity with H1, with H. felis isolates from Italy, Israel, Spain, a ∼92 % identity with the isolate from Austria, and ∼94-98 % with isolates from South Africa. These are the first records of H. felis in cat populations from Greece and indicate that the infection may be present at high prevalences in different regions of the country. Furthermore, the results of the molecular and phylogenetic analysis support a recent hypothesis indicating the existence of a species-complex classification for H. felis. Further studies aiming at elucidating the genetic make-up of Hepatozoon populations and possible variations in terms of geographic distribution and clinical relevance are necessary. The importance of a continuous epizootiological monitoring is crucial for the establishment of preventative and control measures protecting the health of cats living in or travelling to enzootic areas.

Epidemiological Study of Canine Babesiosis and Hepatozoonosis in the South of Romania

PURPOSE

The aim of this study was to evaluate the prevalence and distribution of canine babesiosis and hepatozoonosis in the south of Romania as well as to assess if there are differences in the prevalence between regions in that area.

METHODS

Blood samples from 300 dogs from the south of Romania were screened for the presence of piroplasmids by PCR. Positive samples were further tested for the presence of Babesia spp. and Hepatozoon canis. Pearson's chi-square with Yates correction was used to determine if there is statistical difference between infected populations.

RESULTS

Fifty-four percent (163/300) of the dogs were positive for Hepatozoon spp. or piroplasmids. Forty-eight percent (143/300) were infected with H. canis and 9.6% (29/300) were positive to B. canis. Three percent (9/300) of the dogs were co-infected with Babesia spp. and H. canis. The prevalence of H. canis in the south-west of Romania was significantly higher (p < 0.05) than that of three other regions while the prevalence of Babesia spp. infection in the south-east of the country was significantly higher (p < 0.05) compared to its south-west.

CONCLUSIONS

A high rate of H. canis infection was found in the stray dog population surveyed with the highest infection rate detected in south-western Romania. Babesia canis was found to pose the highest threat in south-eastern Romania, whereas B. vogeli infection was focused in the same region of high H. canis infection in south-western Romania. These infections should be of important concern to veterinarians and dog owners in Romania.

Zoonotic and vector-borne pathogens in tigers from a wildlife safari park, Italy

Infectious diseases by pathogens, including those of zoonotic concern, may act as a primary or contributory cause of threat to wildlife conservation and may represent a risk for human health, mainly for people working at, or visiting the zoological parks. Given the paucity of data on pathogens infecting wild tigers, we investigated the occurrence of infectious agents in this animal species, with a special focus on those of zoonotic concern. Blood and serum samples from tigers (n = 20) living in a wildlife safari park of southern Italy were screened by serological and molecular tests. All animals scored positive for antibodies against Toxoplasma gondii (100%), whereas they displayed different prevalence of seropositivity for Rickettsia conorii (30%), Bartonella henselae (15%) and Leptospira interrogans sv Icterohaemorrhagiae and/or Leptospira kirschneri sv Grippotyphosa (15%). No antibodies against Coxiella burnetii were detected. In addition, 8 tigers (40%) tested molecularly positive to "Candidatus Mycoplasma haemominutum", and 3 (15%) to Hepatozoon canis. No DNA of R. conorii, Bartonella spp., Ehrlichia/Anaplasma spp. and piroplasmids was amplified. The occurrence of tiger infections by bacteria and parasites may represent a risk for morbidity and, in some circumstances, mortality in this endangered species and a source of infection for other animals, including humans. These findings indicate that the circulation of zoonotic pathogens such as T. gondii, R. conorii, L. interrogans sv Icterohaemorrhagiae, "Candidatus Mycoplasma haemominutum" and B. henselae in given environments may represent a relevant health issue considering the close association among animals and humans visiting, or working at, the wildlife safari park. Preventative measures are advocated in order to control ectoparasites and other sources of infection (e.g., small rodents), thus for minimizing the risk of infection for animals as well as for humans.

Identification of tick-borne pathogens in ticks collected from wild animals in Turkey

Many enzootic life cycles involving wild animals and non-nidicolous ixodids are still unknown. Therefore, the aim of this study was to report the identified tick species collected from seven different animal species (red deer, brown bear, gray wolf, Eurasian lynx, red fox, European hare, and Mediterranean spur-thighed tortoise) living in the wild in Turkey and to investigate the presence of a wide range of tick-borne microorganisms in the tick samples obtained from these animals. The collected ticks (n = 98) were identified as Dermacentor reticulatus, Haemaphysalis parva, Hyalomma aegyptium, Hyalomma excavatum, Hyalomma marginatum, Ixodes ricinus, and Rhipicephalus turanicus. All engorged ticks collected from the wild animals and unfed larvae (n = 30) obtained from a single Rh. turanicus female were also analyzed individually for tick-borne bacterial and protozoan agents via PCR-sequencing. The molecular analyses revealed the presence of Babesia sp. tavsan2, Theileria capreoli, four Hepatozoon spp. (Hep. ursi, Hep. canis, Hep. felis, and Hepatozoon sp.), Hemolivia mauritanica, and three SFG rickettsiae (Candidatus Rickettsia barbariae, Ca. R. goldwasserii, and Rickettsia hoogstraalii) in the collected ticks. This represents the first report of Th. capreoli, Hep. ursi, and Ca. R. barbariae in ticks from Turkey. The evolutionary relationships of microbes in the different host and tick species are also discussed. Multiple novel tick-host associations in the tick life cycle were also revealed.

Molecular characterisation and morphological description of two new species of Hepatozoon Miller, 1908 (Apicomplexa: Adeleorina: Hepatozoidae) infecting leukocytes of African leopards Panthera pardus pardus (L.)

BACKGROUND

The African leopard Panthera pardus pardus (L.) is currently listed as a vulnerable species on the IUCN (International Union for the Conservation of Nature) red list of threatened species due to ongoing population declines. This implies that leopard-specific parasites are also vulnerable to extinction. Intracellular apicomplexan haemoparasites from the genus Hepatozoon Miller, 1908 have been widely reported from wild carnivores in Africa, including non-specific reports from leopards. This paper describes two new haemogregarines in captive and wild leopards from South Africa and provides a tabular summary of these species in relation to species of Hepatozoon reported from mammalian carnivores.

METHODS

Blood was collected from nine captive and eight wild leopards at various localities throughout South Africa. Thin blood smears were Giemsa-stained and screened for intraleukocytic haemoparasites. Gamont stages were micrographed and morphometrically compared with existing literature pertaining to infections in felid hosts. Haemogregarine specific primer set 4558F and 2733R was used to target the 18S rRNA gene for molecular analysis. Resulting sequences were compared to each other and with other available representative mammalian carnivore Hepatozoon sequences from GenBank.

RESULTS

Two species of Hepatozoon were found in captive and wild leopards. Of the 17 leopards screened, eight were infected with one or both morphologically and genetically distinct haemogregarines. When compared with other species of Hepatozoon reported from felids, the two species from this study were morphometrically and molecularly distinct. Species of Hepatozoon from this study were observed to exclusively parasitize a particular type of leukocyte, with Hepatozoon luiperdjie n. sp. infecting neutrophils and Hepatozoon ingwe n. sp. infecting lymphocytes. Phylogenetic analysis showed that these haemogregarines are genetically distinct, with Hepatozoon luiperdjie n. sp. and Hepatozoon ingwe n. sp. falling in well supported separate clades.

CONCLUSIONS

To our knowledge, this is the first morphometric and molecular description of Hepatozoon in captive and wild African leopards in South Africa. This study highlights the value of using both morphometric and molecular characteristics when describing species of Hepatozoon from felid hosts.

Who let the cats out? A global meta-analysis on risk of parasitic infection in indoor versus outdoor domestic cats ( Felis catus)

Parasitic infection risks in domestic animals may increase as a result of outdoor activities, often leading to transmission events to and from owners, other domestic animals and wildlife. Furthermore, outdoor access has not been quantified in domestic animals as a risk factor with respect to latitude or parasite transmission pathway. Cats are an ideal model to test parasitic infection risk in outdoor animals because there have been many studies analysing this risk factor in this species; and there is a useful dichotomy in cat ownership between indoor-only cats and those with outdoor access. Thus, we used meta-analysis to determine whether outdoor access is a significant risk factor for parasitic infection in domestic pet cats across 19 different pathogens including many relevant to human, domestic animal and wildlife health, such as Toxoplasma gondii and Toxocara cati. Cats with outdoor access were 2.77 times more likely to be infected with parasites than indoor-only cats. Furthermore, absolute latitude trended towards significance such that each degree increase in absolute latitude increased infection likelihood by 4%. Thus, restricting outdoor access can reduce the risk of parasitic infection in cats and reduce the risk of zoonotic parasite transmission, spillover to sympatric wildlife and negative impacts on feline health.

High prevalence of vector-borne pathogens in domestic and wild carnivores in Iraq

Vector-borne diseases (VBDs) of domestic and wild carnivores are of major public health concern both in industrialized and developing countries, especially in poor socioeconomic settings. War-torn areas specifically suffer from absence of veterinary surveillance of VBDs, resulting in lack of scientific knowledge on this topic. To investigate occurence and prevalence of several vector-borne pathogens (VBPs) in some carnivore species from Iraq, blood samples (n = 397) were obtained from 190 canids [97 stray dogs (Canis familiaris), 55 jackals (Canis aureus) and 38 red foxes (Vulpes vulpes)] and 207 stray cats (Felis catus) collected during a feral animal control and zoonotic disease surveillance program in several United States military bases in Iraq. The presence of Babesia spp., Hepatozoon spp., Ehrlichia spp., Anaplasma spp., Dirofilaria spp. and Leishmania spp. DNA was molecularly investigated. Out of 397 animals tested, 176 (44.3%; 95% CI: 39.5-49.2%) were positive for at least one pathogen with the highest prevalence in foxes (73.7%; 95% CI: 58-85%), followed by jackals (54.5%; 95% CI: 41.5-67%), dogs (38.1%; 29.1-48.1%) and cats (39.1%; 95% CI: 32.7-45.9%). Up to five pathogens were diagnosed in dogs. Hepatozoon canis was the most prevalent VBP in jackals (49.1%; 95% CI: 36.4-61.9%), foxes (47.3%; 95% CI: 32.5-62.7%) and dogs (33%; 95% CI: 24.4-42.8%), whereas Hepatozoon felis was the only species detected in cats (39.1%; 95% CI: 32.7-45.9%). A species of Babesia related to but different from Babesia lengau and designated as Babesia sp. MML was detected in six foxes (15.8%; 95% CI: 7.4-30.4%) and in one jackal (1.8%; 95% CI: 0.3-9.6%). This finding suggested the existence of a new species in the genus Babesia as inferred by molecular and phylogenetical analysis. Further, Babesia vulpes was identified only in two foxes (5.3%; 95% CI: 1.5-17.3%). All samples were negative for Leishmania spp. and Ehrlichia spp. Co-infection with H. canis and Babesia spp. was the most prevalent (5/176, 2.8%, i.e., 4 foxes and 1 jackal), followed by H. canis and Dirofilaria immitis (1/176, 1.3%, i.e., in 1 jackal), H. canis and Dirofilaria repens or Acanthocheilonema reconditum (1/176, 1.3%, i.e., in one dog, each). Data presented fill gaps into knowledge of VBPs in dogs, cats and wild canids in Iraq, indicating that different pathogens circulate amongst animal populations living in the same areas, possibly sharing the same tick vectors. Large-scale surveys are urgently needed to further assess VBPs distribution in Iraq and establish preventative strategies in domestic animals to minimize the risk of infection for animals and humans.

First autochthonous case of clinical Hepatozoon felis infection in a domestic cat in Central Europe

Three different Hepatozoon (Apicomplexa, Hepatozoidae) species have been described infecting domestic cats in Europe (i.e. H. felis, H. canis and H. silvestris), however, reports on clinical hepatozoonosis are uncommon and treatment protocols are not clearly defined.

A six-year-old male European short-hair cat from Austria presented poor general condition, lethargy, anorexia, icterus, a painful abdomen, fever, ruffled hair and a tick infestation, and it had never left Austria. Laboratory tests revealed leukopenia, thrombocytopenia and increased serum levels of symmetric dimethylarginine (SDMA) and bilirubin. In May Grünwald-Giemsa-stained blood smears, structures resembling Hepatozoon gamonts were observed inside neutrophil granulocytes. A PCR targeting a fragment of the 18S rRNA gene of Hepatozoon spp. and DNA sequencing allowed the diagnosis of H. felis-DNA in blood samples. The cat was treated with imidocarb dipropionate (6 mg/kg body weight, repeated after 14 days) and doxycycline monohydrate (5 mg/kg body weight twice a day, p.o., for four weeks) and recovered completely. A broad haematological and biochemical laboratory control after six months showed all evaluated parameters under normal ranges. Coinfection with other feline pathogens (i.e. feline leukaemia virus, feline immunodeficiency virus, feline Coronavirus, Leishmania and Dirofilaria immitis) could not be detected.

This study reveals the presence of H. felis in Austria and provides more evidence on the geographical distribution and pathogenicity of this parasite for domestic cats. To the authors' knowledge, this is the first autochthonous case of feline hepatozoonosis in Central Europe.

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Clinical Hepatozoon felis infection in a domestic cat was diagnosed in Austria.

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The diagnosis was achieved by microscopy of blood smears, PCR and DNA-sequencing.

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Possible coinfections with other feline pathogens were ruled-out.

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The cat recovered completely after treatment with imidocarb and doxycycline.

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This represents the first autochthonous case of feline hepatozoonosis in Central Europe.

Molecular detection of Hepatozoon felis in cats from Maio Island, Republic of Cape Verde and global distribution of feline hepatozoonosis

Background

Vector-borne diseases are emerging worldwide and have an important zoonotic relevance. In the last few years, the interest in vector-borne pathogens in cats has increased. However, studies on feline vector-borne pathogens on tropical islands are lacking. Islands differ from continental countries because they have an enclosed population of animals, with all year presence of the vectors and, most often, without vector control measures. This study focused on the molecular identification and phylogenetic analysis of vector-borne pathogens in autochthonous cats with a mixed indoor–outdoor lifestyle from Maio Island, Cape Verde archipelago.

Methods

Blood samples were collected from 80 asymptomatic cats, representing almost a quarter of the total cat population of the island. The presence of DNA of protozoa of the genus Hepatozoon and bacteria belonging to family Anaplasmataceae and to genus Bartonella was assessed by PCR and phylogenetic analysis was conducted. Statistical analysis was performed to identify risk factors associated with infection. For feline hepatozoonosis, a worldwide dataset of Hepatozoon felis sequences retrieved from mammal species and vectors along with Hepatozoon spp. sequences retrieved from felids was generated, phylogenetically analyzed and the geographical and host distribution was assessed.

Results

Hepatozoon felis genotype I was identified in 12 (15%) cats from Maio Island whereas none of the cats were PCR positive for the other pathogens tested. No significant association of H. felis infection with age, sex, location or presence of vectors was observed by statistical analysis in Cape Verde’s cats. Phylogenetic analysis on the worldwide dataset of feline Hepatozoon sequences showed two significant distinct clades for H. felis genotype I and II. Different geographical distributions were assessed: H. felis genotype I was the only genotype found in Africa and has been reported worldwide, with the exception of Japan and Brazil where only H. felis genotype II has been reported.

Conclusions

The identification of H. felis genotype I in cats in Maio Island highlights the need to further investigate the significance of H. felis genotypes and to clarify the epidemiological aspects of this infection.

Electronic supplementary material

The online version of this article (10.1186/s13071-019-3551-3) contains supplementary material, which is available to authorized users.

Vector-borne pathogens affecting shelter dogs in eastern Crete, Greece

Canine pathogens transmitted by blood-sucking arthropods are of significant importance for veterinary and, in some cases, human health. However, they are still underestimated and rarely investigated in many parts of the Mediterranean region, mostly due to financial reasons. Therefore, in the present paper, we investigated the occurrence of blood-associated pathogens affecting dogs in Crete, Greece. For this purpose, blood samples from 103 shelter dogs were screened for the pathogens by PCR and serological tests. Overall, samples from 43 dogs scored positive for at least one pathogen (41.8%). In particular, antibodies to Leishmania infantum were detected in 26 dogs (25.2%), and 15 and 11 animals were positive for Hepatozoon canis (14.6%) and Mycoplasma haemocanis (10.7%) by PCR, respectively. Co-infections were recorded in nine animals. Clinical signs indicative of infection (alterations of skin or coat or reduced body condition) were detected in 10 animals, four of which were infected with one pathogen, three with two pathogens. Based on the results obtained, dogs from Crete appear to be frequently exposed to several blood-borne pathogens, including agents of zoonotic concern. Given that some of the pathogens were reported for the first time in this area, results presented in our study should improve the awareness of the local veterinarians and of dog rescue organisations in order to reduce disease burden on stray and owned dogs and to control the spread of canine vector-borne diseases from Greece to non-endemic areas by travelling or exported infected dogs.