Molecular detection of Anaplasma bovis, Ehrlichia canis and Hepatozoon felis in cats from Luanda, Angola

Genomic characters of Anaplasma bovis and genetic diversity in China

The emergence of Anaplasma bovis or A. bovis-like infection in humans from China and the United States of America has raised concern about the public health importance of this pathogen. Although A. bovis has been detected in a wide range of ticks and mammals in the world, no genome of the pathogen is available up to now, which has prohibited us from better understanding the genetic basis for its pathogenicity. Here we describe an A. bovis genome from metagenomic sequencing of an infected goat in China. Anaplasma bovis had the smallest genome of the genus Anaplasma, and relatively lower GC content. Phylogenetic analysis of single-copy orthologue sequence showed that A. bovis was closely related to A. platys and A. phagocytophilum, but relatively far from intraerythrocytic Anaplasma species. Anaplasma bovis had 116 unique orthogroups and lacked 51 orthogroups in comparison to other Anaplasma species. The virulence factors of A. bovis were significantly less than those of A. phagocytophilum, suggesting less pathogenicity of A. bovis. When tested by specific PCR assays, A. bovis was detected in 23 of 29 goats, with an infection rate up to 79.3% (95% CI: 64.6% ∼94.1%). The phylogenetic analyses based on partial 16S rRNA, gltA and groEL genes indicated that A. bovis had high genetic diversity. The findings of this study lay a foundation for further understanding of the biological characteristics and genetic diversity of A. bovis, and will facilitate the formulation of prevention and control strategies.

Phylogenetic analysis of Ehrlichia species isolated from horses and dogs in Iran

This study aimed to determine the prevalence and phylogenetic analysis of Ehrlichia spp. in horses and dogs in Iran. Blood samples were collected from 400 animals, including 200 horses and 200 dogs, from five different provinces in Iran. Polymerase chain reaction (PCR) was used to detect Ehrlichia spp. based on amplification of the 16S rRNA gene. The semi-nested PCR method was used to amplify the dsb, TRP36, and gltA genes. The results showed that 4.5 % of the samples (3 % horses and 6 % dogs) were positive for Ehrlichia sp. The highest prevalence was observed in Kerman and Khuzestan, while the lowest was found in West Azerbaijan, Golestan, and Mazandaran. The study suggests that the populations of dogs and horses in the country should be considered important factors in the epidemiology of ehrlichiosis. Phylogenetic analysis based on the dsb and TRP36 genes revealed that the prevalent species were E. canis and E. ruminantium.

Anaplasma Species in Africa-A Century of Discovery: A Review on Molecular Epidemiology, Genetic Diversity, and Control

Anaplasma species, belonging to the family Anaplasmataceae in the order Rickettsiales, are obligate intracellular bacteria responsible for various tick-borne diseases of veterinary and human significance worldwide. With advancements in molecular techniques, seven formal species of Anaplasma and numerous unclassified species have been described. In Africa, several Anaplasma species and strains have been identified in different animals and tick species. This review aims to provide an overview of the current understanding of the molecular epidemiology and genetic diversity of classified and unclassified Anaplasma species detected in animals and ticks across Africa. The review also covers control measures that have been taken to prevent anaplasmosis transmission on the continent. This information is critical when developing anaplasmosis management and control programs in Africa.

Molecular Detection of Tick-Borne Agents in Cats from Southeastern and Northern Brazil

Even though the epidemiology of tick-borne agents (TBA) in dogs has been extensively investigated around the world, the occurrence, vectors involved, and molecular identity of these agents in cats remains elusive in many regions. Among TBA, Ehrlichia, Anaplasma, Babesia, Cytauxzoon, and Hepatozoon are responsible for diseases with non-specific clinical signs in cats, making essential the use of molecular techniques for accurate diagnosis and proper treatment. The present work aimed to investigate the occurrence and molecular identity of tick-borne agents (Ehrlichia, Anaplasma, Babesia/Theileria, Cytauxzoon, and Hepatozoon) in cats from southeastern (states of São Paulo (SP) and Minas Gerais (MG)) and northern (state of Rondônia (RO)) Brazil. For this purpose, 390 blood samples were collected from domiciled cats in MG (n = 155), SP (n = 151), and RO(n = 84) states, submitted to DNA extraction and PCR assays for Ehrlichia spp. (dsb gene), Anaplasma spp. (rrs gene), piroplasmids (18S rRNA gene), and Hepatozoon spp. (18S rRNA gene), sequencing, and phylogenetic inferences. The overall positivity for Anaplasma spp., Ehrlichia spp., Babesia/Theileria spp., Cytauxzoon spp., and Hepatozoon spp. were 7.4% (12.3% (MG) and 6.6% (SP)), 2% (4.5% (MG) and 0.6% (SP)), 0.7% (0.6% (MG), 0.6% (SP) and 1.2% (RO)), 27.2% (41.9% (MG), 24.5% (SP) and 4.8% (RO), and 0%, respectively. The phylogenetic analysis grouped the obtained sequences with ‘Candidatus Anaplasma amazonensis’, A. platys, B. vogeli, and Cytauxzoon sp. previously detected in wild felids from Brazil. qPCR specific for E. canis based on the dsb gene confirmed the molecular identity of the detected ehrlichial agent. The present study expanded the list and geographical distribution of hemoparasites in cats. ‘Candidatus Anaplasma amazonensis’, recently detected in sloths from northern Brazil, was described for the first time in cats. This is the first report of piroplasmids infecting cats in northern Brazil. Coinfection by Cytauxzoon and other TBA (Ehrlichia, Anaplasma, and B. vogeli) reported in the present study raises the need for veterinary practitioners’ awareness of cats parasitized by multiple TBA.

Molecular detection of Anaplasma spp., Babesia spp. and Theileria spp. in yaks (Bos grunniens) and Tibetan sheep (Ovis aries) on the Qinghai-Tibetan Plateau, China

BACKGROUND

Anaplasma, Babesia and Theileria are tick-borne pathogens (TBPs) that affect livestock worldwide. However, information on these pathogens in yaks (Bos grunniens) and Tibetan sheep (Ovis aries) on the Qinghai-Tibet Plateau (QTP), China, is limited. In this study, Anaplasma spp., Babesia spp. and Theileria spp. infections were assessed in yaks and Tibetan sheep from Qinghai Province.

METHODS

A total of 734 blood samples were collected from 425 yaks and 309 Tibetan sheep at nine sampling sites. Standard or nested polymerase chain reaction was employed to screen all the blood samples using species- or genus-specific primers.

RESULTS

The results showed that 14.1% (60/425) of yaks and 79.9% (247/309) of Tibetan sheep were infected with at least one pathogen. Anaplasma ovis, Anaplasma bovis, Anaplasma capra, Anaplasma phagocytophilum, Babesia bovis and Theileria spp. were detected in this study, with total infection rates for all the assessed animals of 22.1% (162/734), 16.3% (120/734), 23.6% (173/734), 8.2% (60/734), 2.7% (20/734) and 19.3% (142/734), respectively. For yaks, the infection rate of A. bovis was 6.4% (27/425), that of B. bovis was 4.7% (20/425) and that of Theileria spp. was 3.3% (14/425). Moreover, 52.4% (162/309) of the Tibetan sheep samples were infected with A. ovis, 30.1% (93/309) with A. bovis, 56.0% (173/309) with A. capra, 19.4% (60/309) with A. phagocytophilum and 41.4% (128/309) with Theileria spp.

CONCLUSIONS

This study revealed the prevalence of Anaplasma spp., Babesia spp. and Theileria spp. in yaks and Tibetan sheep in Qinghai Province, China, and provides new data for a better understanding of the epidemiology of TBPs in these animals in this area of the QTP, China.

Molecular screening indicates high prevalence and mixed infections of Hepatozoon parasites in wild felines from South Africa

Genetic diversity within partial 18S rRNA sequences from Hepatozoon protozoan parasites from wild felines in South Africa was assessed and compared with data from domestic cats to assess patterns of host specificity. Lions, leopards, servals, a caracal and an African wildcat were all positive for parasites of the Hepatozoon felis-complex. However, haplotypes were not species-specific, and potential mixed infections were widespread. Additional genetic markers are needed to untangle the extremely complex situation of these parasites in both domestic cats and wild felines in South Africa.

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.

Role of vector-borne pathogens in the development of fever in cats: 2. Tick- and sandfly-associated diseases

PRACTICAL RELEVANCE

There has been increasing identification of vector-borne pathogens in cats presented to veterinary clinics around the world for evaluation of fever and the associated secondary effects, such as signs of depression and loss of appetite.

AIM

The aim of this article is to summarize the clinically relevant information concerning fever in cats that is associated with pathogens vectored by ticks or sandflies, with an emphasis on presenting clinical abnormalities and optimal diagnostic, treatment and prevention strategies. Fever in cats associated with pathogens known or suspected to be vectored by fleas was discussed within Part 1 of this two-part article series.

Molecular evidence of Anaplasma infection in naturally affected domestic cats of Pakistan

Feline anaplasmosis is considered as an emerging tick-borne disease of zoonotic potential. The aim of current study was to investigate the molecular prevalence of anaplasmosis, associated risk factors, and alterations in hematological parameters of domestic cats from Lahore, Pakistan. Blood samples of 100 domestic cats from district Lahore were examined microscopically and the extracted genomic DNA from each sample was processed for the amplification of 16 S rRNA gene of Anaplasma. PCR confirmed isolates were purified for sequencing. The data regarding the risk factors was collected in a predesigned questionnaire and statistically analyzed by logistic regression analysis. The study found a molecular prevalence of 13% (13/100) among analyzed blood samples. The nucleotide analysis of Anaplasmataceae species sequences amplified by PCR showed high resemblance (99%) with isolates from Korea, Japan, Malaysia, Philippines, and India. The potential risk factors found to be significantly associated (p < 0.05) with disease dynamics based on the Chi-Square test were tick infestation on studied animals, previous tick history, tick control status, house hygiene, and housing type. A significant (p < 0.05) decrease in the number of platelets, erythrocytes, hemoglobin level, and pack cell volume was observed in cats suffering from anaplasmosis compared to the healthy ones. The current study is the first report of Anaplasma infection in domestic cats of Pakistan. This study will be effectual in designing the control strategies for this disease.

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.

Feline Vector-Borne Diseases in North America

"In North America, with the exceptions of Bartonella henselae and Cytauxzoon felis, feline vector-borne diseases (FVBDs) have been minimally studied in domestic cats. Cats can be infected with many of the same vector-borne pathogens that infect dogs. Nonspecific clinical signs linked to FVBDs and low prevalence of certain vector-borne pathogens contribute to a limited awareness of FVBDs in sick cats. As clinicians become informed about FVBDs and as vector-borne disease diagnostics are routinely applied to evaluate sick cats, we will gain a stronger understanding of vector-borne pathogens in cats. This article focuses on recent findings related to FVBDs."

Ehrlichia spp. infection in domestic cats from Rio de Janeiro State, southeast Brazil

Ehrlichiosis is caused by agents belonging to Ehrlichia genus. Despite the frequent reports on the serological and molecular detection of E. canis in dogs in Brazil, there is scant data on ehrlichiosis in brazilian cats. This study aimed at investigating the occurrence of Ehrlichia spp. in domestic cats from Greater Rio de Janeiro, and evaluating hematological changes associated with this rickettsial infection. We searched for IgG antibodies against E. canis on blood samples of 216 cats by Indirect Fluorescence Assay (IFA). Additionally, we performed nested PCR (nPCR) and real-time PCR (qPCR) assays targeting E. canis-16S rRNA and dsb gene, respectively. Fifty-seven (26.4%) cats were seropositive for Ehrlichia spp. by IFA. Ehrlichia spp.-16S rRNA gene fragments were detected in 3 cats (1.4%). Although the obtained 16S rRNA sequences showed 99 to 100% identity with E. canis, cats were negative in qPCR. Anemia, thrombocytopenia, leukocytosis, left shift neutrophil and hyperproteinemia were observed. Anemia was statistically associated with seropositivity to E. canis and kittens showed lower positivity rates (p<0.05). This study showed that Ehrlichia spp. occur in domestic cats from Greater Rio de Janeiro. Further studies involving culture isolation are much needed to more precisely characterize these organisms.

Diversity of Anaplasma and Ehrlichia/Neoehrlichia Agents in Terrestrial Wild Carnivores Worldwide: Implications for Human and Domestic Animal Health and Wildlife Conservation

Recently, the incidence and awareness of tick-borne diseases in humans and animals have increased due to several factors, which in association favor the chances of contact among wild animals and their ectoparasites, domestic animals and humans. Wild and domestic carnivores are considered the primary source of tick-borne zoonotic agents to humans. Among emergent tick-borne pathogens, agents belonging to family Anaplasmataceae (Order Rickettsiales) agents stand out due their worldwide distribution and zoonotic potential. In this review we aimed to review the genetic diversity of the tick-transmitted genera Ehrlichia, Anaplasma and "Candidatus Neoehrlichia sp." in wild carnivores Caniformia (Canidae, Mustelidae and Ursidae) and Feliformia (Felidae, Hyanidae, Procyonidae and Viverridae) worldwide, discussing the implications for human and domestic animal health and wildlife conservation. Red foxes (Vulpes vulpes) have been identified as hosts for Anaplasma spp. (A. phagocytophilum, Anaplasma ovis, A. platys), Ehrlichia canis and "Candidatus Neoehrlichia sp." (FU98 strain) and may contribute to the maintaenance of A. phagocytophilum in Europe. Raccoons (Procyon lotor) have been reported as hosts for E. canis, A. bovis, "Candidatus Neoehrlichia lotoris" and A. phagocytophilum, and play a role in the maintenance of A. phagocytophilum in the USA. Raccoon dogs (Nyctereutes procyonoides) may play a role as hosts for A. bovis and A. phagocytophilum. New Ehrlichia and/or Anaplasma genotypes circulate in wild canids and felids from South America and Africa. While Ehrlichia sp. closely related to E. canis has been reported in wild felids from Brazil and Japan, Anaplasma sp. closely related to A. phagocytophilum has been detected in wild felids from Brazil and Africa. Red foxes and mustelids (otters) are exposed to E. canis in countries located in the Mediaterranean basin, probably as a consequence of spillover from domestic dogs. Similarly, E. canis occurs in procyonids in North (raccoons in USA, Spain) and South (Nasua nasua in Brazil) Hemispheres, in areas where E. canis is frequent in dogs. While "Candidatus Neoehrlichia lotoris" seems to be a common and specific agent of raccoons in the USA, "Candidatus Neoehrlichia sp." (FU98 strain) seems to show a broader range of hosts, since it has been detected in red fox, golden jackal (Canis aureus) and badger (Meles meles) in Europe so far. Brown (Ursus arctos) and black (Ursus americanus) bears seem to play a role as hosts for A. phagocytophilum in the North Hemisphere. Anaplasma bovis has been detected in wild Procyonidae, Canidae and Felidae in Asia and Brazil. In order to assess the real identity of the involved agents, future works should benefit from the application of MLST (Multi Locus Sequence Typing), WGS (Whole Genome Sequencing) and NGS (Next Generation Sequencing) technologies aiming at shedding some light on the role of wild carnivores in the epidemiology of Anaplasmataceae agents.