Changes in the Seroprevalence of Tick-Borne Rickettsia and Ehrlichia Among Soldiers-Fort Liberty, North Carolina, 1991-2019.

We obtained samples from the Department of Defense Serum Repository from soldiers who were stationed at Fort Liberty, North Carolina, between 1991 and 2019 to assess temporal trends in tick-borne rickettsiosis and ehrlichiosis. Serological evidence of infection was common, with nearly 1 in 5 (18.9%) demonstrating antibodies. We observed significant decreases in Rickettsia seroprevalence (adjusted odds ratio [aOR], 0.42 [95% CI, .27-.65], P = .0001) while over the same period Ehrlichia seroprevalence, albeit less common, nearly doubled (aOR, 3.61 [95% CI, 1.10-13.99], P = .048). The increase in Ehrlichia seroprevalence likely reflects increased transmission resulting from the expanding geographic range of the lone star tick.

A molecular toolbox for fast and convenient diagnosis of emerging and reemerging bacterial pathogens causing fever of intermediate duration.

PURPOSE: Fever of intermediate duration (FID) is defined as a fever in the community without a specific origin or focus, with a duration between 7 and 28 days. FID is often caused by pathogens associated with animal contact or their arthropods parasites, such as ticks, fleas, or lice. The purpose of this work is to design a collection of molecular tools to promptly and accurately detect common bacterial pathogens causing FID, including bacteria belonging to genera Rickettsia, Bartonella, Anaplasma, and Ehrlichia, as well as Coxiella burnetii. METHODS: Reference DNA sequences from a collection of Rickettsia, Bartonella, Anaplasma, and Ehrlichia species were used to design genus-specific primers and FRET probes targeted to conserved genomic regions. For C. burnetii, primers previously described were used, in combination with a newly designed specific probe. Real-time PCR assays were optimized using reference bacterial genomic DNA in a background of human genomic DNA. RESULTS: The four real-time PCR assays can detect as few as ten copies of target DNA from those five genera of FDI-causing bacteria in a background of 300 ng of human genomic DNA, mimicking the low microbial load generally found in patient's blood. CONCLUSION: These assays constitute a fast and convenient "toolbox" that can be easily implemented in diagnostic laboratories to provide timely and accurate detection of bacterial pathogens that are typical etiological causes of febrile syndromes such as FID in humans.

Phenotypic and genotypic characterization of ticks and tick-borne pathogens from cattle in selected villages of Greater Letaba Municipality in Limpopo Province, South Africa.

Ticks are blood ectoparasites that feed on domestic, wild animals and humans. They spread a variety of infections such as protozoa, viruses, and bacteria. Moreover, cattle reared by smallholder farmers are susceptible to ticks and tick-borne pathogens. Therefore, accurate identification of ticks and detection of tick-borne pathogens is crucial. The main aim of this study was to identify and characterize ticks and tick-borne pathogens from selected villages in Greater Letaba Municipality, Limpopo Province, using morphological and molecular techniques. A total of 233 ticks were collected from cattle and identified morphologically using appropriate morphological keys. The following tick species were identified: Amblyomma hebraeum, Hyalomma rufipes, Hyalomma truncatum, Rhipicephalus appendiculatus, Rhipicephalus (Boophilus) decoloratus, Rhipicephalus (Boophilus) microplus, Rhipicephalus evertsi evertsi, and Rhipicephalus sanguineus. Rhipicephalus spp. was the most common species accounting to 73.8% of the identified ticks. The genomic DNA was extracted from the whole tick for tick identification and from midguts of the ticks for the detection of tick-borne pathogens, followed by amplification and sequencing. A total of 27 samples were positive for tick-borne pathogens: 23 samples tested positive for Theileria and four samples tested positive for Ehrlichia. Anaplasma and Rickettsial OmpB could not be detected from any of the samples. There was no obvious grouping of ticks and tick-borne pathogens on the bases of their locality. The findings of this study confirm previous reports that indicated that cattle reared by smallholder farmers harbor various ticks and tick-borne pathogens of veterinary, public health, and economic importance. Regular monitoring of tick infestations in villages around the study areas is recommended to avoid disease outbreaks.

Tick-borne microorganisms in Amblyomma tigrinum (Acari: Ixodidae) from the Patagonian region of Argentina.

This study presents the results of the molecular detection of tick-borne microorganisms in Amblyomma tigrinum Koch collected near the city of Viedma, Río Negro, Argentina. Ticks were collected in their non-parasitic stage, on pet dogs and on Lycalopex gymnocercus (Pampa fox). Also, six tick samples from humans were analyzed. All ticks were morphologically identified to species level and genomic DNA was extracted. The DNA samples were examined by end point PCR assays to amplified DNA of Anaplasma sp., Babesia sp., Ehrlichia sp., Rickettsia sp. and Theileria sp. Although all tested DNA samples from the collected ticks resulted negative to the detection of Piroplasmida and Rickettsia spp., 16 samples (16.5%, including all hosts) were positive in the 16S rDNA gene PCR that detects bacteria from the Anaplasmataceae family. Phylogenetic analysis of seven obtained partial sequences resulted in the identification of three bacteria: two Ehrlichia spp. (related to Ehrlichia sp. strain Iberá and strain Viedma) and Candidatus Anaplasma boleense. The latter finding represents the first detection of this novel Candidatus species in A. tigrinum. Based on the results of this study, it must be assumed that the diversity of bacteria of the Anaplasmataceae family in Argentina is greater than previously thought, and that these bacteria can infect a wide range of domestic and wild animals.

Tick-borne bacterial agents in Hyalomma asiaticum ticks from Xinjiang Uygur Autonomous Region, Northwest China.

BACKGROUND: Hyalomma ticks are widely distributed in semi-arid zones in Northwest China. They have been reported to harbor a large number of zoonotic pathogens. METHODS: In this study, a total of 334 Hyalomma asiaticum ticks infesting domestic animals were collected from four locations in Xinjiang, Northwest China, and the bacterial agents in them were investigated. RESULTS: A putative novel Borrelia species was identified in ticks from all four locations, with an overall positive rate of 6.59%. Rickettsia sibirica subsp. mongolitimonae, a human pathogen frequently reported in Europe, was detected for the second time in China. Two Ehrlichia species (Ehrlichia minasensis and Ehrlichia sp.) were identified. Furthermore, two Anaplasma species were characterized in this study: Candidatus Anaplasma camelii and Anaplasma sp. closely related to Candidatus Anaplasma boleense. It is the first report of Candidatus Anaplasma camelii in China. CONCLUSIONS: Six bacterial agents were reported in this study, many of which are possible or validated pathogens for humans and animals. The presence of these bacterial agents may suggest a potential risk for One Health in this area.

Molecular screening of tick-borne microorganisms in ticks from rural areas of Panama, with the first record of Ehrlichia minasensis in Rhipicephalus microplus from Central America.

During a molecular screening of rickettsial, borrelial and protozoal agents in ticks from rural areas of Panama, we detected DNA of Rickettsia amblyommatis in four Amblyomma mixtum collected from horses in a locality in Los Santos province. Ehrlichia minasensis and Anaplasma marginale were identified from three and two Rhipicephalus microplus, respectively, collected on cows from Chiriqui province. No DNA from other tick-borne agents was found. These results increase the information of R. amblyommatis and A. marginale in Panama, and also mark the first record of E. minasensis in Central America.

Ehrlichia effector TRP120 manipulates bacteremia to facilitate tick acquisition.

Ehrlichia species are obligatory intracellular bacteria that cause a potentially fatal disease, human ehrlichiosis. The biomolecular mechanisms of tick acquisition of Ehrlichia and transmission between ticks and mammals are poorly understood. Ehrlichia japonica infection of mice recapitulates the full spectrum of human ehrlichiosis. We compared the pathogenicity and host acquisition of wild-type E. japonica with an isogenic transposon mutant of E. japonica that lacks tandem repeat protein 120 (TRP120) (ΔTRP120). Both wild-type and ΔTRP120 E. japonica proliferated similarly in cultures of mammalian and tick cells. Upon inoculation into mice, both wild-type and ΔTRP120 E. japonica multiplied to high levels in various tissues, with similar clinical chemistry and hematologic changes, proinflammatory cytokine induction, and fatal disease. However, the blood levels of ΔTRP120 E. japonica were almost undetectable within 24 h, whereas the levels of the wild type increased exponentially. Greater than 90% of TRP120 was released from infected cells into the culture medium. Mouse blood monocytes exposed to native TRP120 from culture supernatants showed significantly reduced cell surface expression of the transmigration-related markers Ly6C and CD11b. Larval ticks attached to mice infected with either wild-type or ΔTRP120 E. japonica imbibed similar amounts of blood and subsequently molted to nymphs at similar rates. However, unlike wild-type E. japonica, the ΔTRP120 mutant was minimally acquired by larval ticks and subsequent molted nymphs and, thus, failed to transmit to naïve mice. Thus, TRP120 is required for bacteremia but not disease. These findings suggest a novel mechanism whereby an obligatory intracellular bacterium manipulates infected blood monocytes to sustain the tick-mammal transmission cycle. IMPORTANCE: Effective prevention of tick-borne diseases such as human ehrlichiosis requires an understanding of how disease-causing organisms are acquired. Ehrlichia species are intracellular bacteria that require infection of both mammals and ticks, involving cycles of transmission between them. Mouse models of ehrlichiosis and tick-mouse transmission can advance our fundamental understanding of the pathogenesis and prevention of ehrlichiosis. Herein, a mutant of Ehrlichia japonica was used to investigate the role of a single Ehrlichia factor, named tandem repeat protein 120 (TRP120), in infection of mammalian and tick cells in culture, infection and disease progression in mice, and tick acquisition of E. japonica from infected mice. Our results suggest that TRP120 is necessary only for Ehrlichia proliferation in circulating mouse blood and ongoing bacteremia to permit Ehrlichia acquisition by ticks. This study provides new insights into the importance of bacterial factors in regulating bacteremia, which may facilitate tick acquisition of pathogens.

Prevalence of subclinical infectious agents in a blood donor population tested on every donation.

OBJECTIVES: This study aimed to assess the prevalence of blood-borne infectious agents in healthy, client-owned dogs from a blood donor population in Portugal and Spain, and to address the importance of a screening protocol on every donation. MATERIALS AND METHODS: Client-owned healthy dogs were tested before each donation on a veterinary blood bank. Blood samples from new potential donors, and from regular donors, were tested by real-time polymerase chain reaction for Leishmania species, Ehrlichia species, Brucella species, Babesia species and Anaplasma species Serological tests were also performed for Leishmania species, Ehrlichia species and Dirofilaria immitis. All donors were tested for every infectious agent in each donation. RESULTS: The study found that out of a total of 8036 donors and 35,120 samples tested, 3.9% of blood donors tested positive for at least one of the agents, with the most prevalent being Anaplasma species (2.1%). Serological tests also revealed positive results in 14.0% of donors, with the highest percentage for Leishmania species (7.7%). Moreover, the study found that 28.2% of positive results were from dogs with negative results in donations performed 3 to 12 months before, and 18.0% of positive results were recent infections. CLINICAL SIGNIFICANCE: These findings indicate a high prevalence of infectious agents in seemingly healthy, selected dogs eligible to become blood donors in the Iberian Peninsula, highlighting the importance of regular testing on every donation. This study emphasises the importance of a regular screening protocol for every donation instead of annual testing, as is commonly performed in veterinary medicine.

Detection of Anaplasma and Ehrlichia bacteria in humans, wildlife, and ticks in the Amazon rainforest.

Tick-borne bacteria of the genera Ehrlichia and Anaplasma cause several emerging human infectious diseases worldwide. In this study, we conduct an extensive survey for Ehrlichia and Anaplasma infections in the rainforests of the Amazon biome of French Guiana. Through molecular genetics and metagenomics reconstruction, we observe a high indigenous biodiversity of infections circulating among humans, wildlife, and ticks inhabiting these ecosystems. Molecular typing identifies these infections as highly endemic, with a majority of new strains and putative species specific to French Guiana. They are detected in unusual rainforest wild animals, suggesting they have distinctive sylvatic transmission cycles. They also present potential health hazards, as revealed by the detection of Candidatus Anaplasma sparouinense in human red blood cells and that of a new close relative of the human pathogen Ehrlichia ewingii, Candidatus Ehrlichia cajennense, in the tick species that most frequently bite humans in South America. The genome assembly of three new putative species obtained from human, sloth, and tick metagenomes further reveals the presence of major homologs of Ehrlichia and Anaplasma virulence factors. These observations converge to classify health hazards associated with Ehrlichia and Anaplasma infections in the Amazon biome as distinct from those in the Northern Hemisphere.

Distribution and pathogen prevalence of field-collected ticks from south-western Korea: a study from 2019 to 2022.

Hard ticks are known vectors of various pathogens, including the severe fever with thrombocytopenia syndrome virus, Rickettsia spp., Coxiella burnetii, Borrelia spp., Anaplasma phagocytophilum, and Ehrlichia spp. This study aims to investigate the distribution and prevalence of tick-borne pathogens in southwestern Korea from 2019 to 2022. A total of 13,280 ticks were collected during the study period, with H. longicornis accounting for 86.1% of the collected ticks. H. flava, I. nipponensis and A. testudinarium comprised 9.4%, 3.6%, and 0.8% of the ticks, respectively. Among 983 pools tested, Rickettsia spp. (216 pools, 1.6% MIR) were the most prevalent pathogens across all tick species, with R. japonica and R. monacensis frequently detected in I. nipponensis and Haemaphysalis spp., respectively. Borrelia spp. (28 pools, 0.2% MIR) were predominantly detected in I. nipponensis (27 pools, 13.8% MIR, P < 0.001). Co-infections, mainly involving Rickettsia monacensis and Borrelia afzelii, were detected in I. nipponensis. Notably, this study identified R. monacensis for the first time in A. testudinarium in South Korea. These findings offer valuable insights into the tick population and associated pathogens in the region, underscoring the importance of tick-borne disease surveillance and prevention measures.

Assessment of the effect of long-term serum storage for retrospective serologic diagnosis of canine monocytic ehrlichiosis (Ehrlichia canis).

There is currently sparse information on the possible effect of long-term storage of serum specimens for the retrospective serodiagnosis of canine monocytic ehrlichiosis (CME). The aim of this study was to assess the agreement between the original serologic outcome and the results of a repeat indirect fluorescent antibody (IFA) assay for the detection of IgG antibodies against E. canis. A secondary aim was to compare the diagnostic performance of two commercially available point-of-care (POC) immunochromatographic (IC) assays. Archived serum samples originally tested as positive (n=66) or negative (n=19) for E. canis IgG antibodies and kept frozen at -20°C for a median of 22 years, were retrospectively examined by IFA and by two POC IC assays. Cohen's Kappa coefficient (0.748, p < 0.0001), indicated a substantial agreement between the original and repeat serologic testing results. An almost identical high sensitivity and moderate specificity were established for the two POC IC assays. Canine serum specimens on long-term storage may still be of value for seroepidemiologic surveys investigating the exposure to E. canis.

Cervids as Sentinels for Rickettsia spp. in Portugal.

Cervids are highly exposed to ticks, however, their role in the life cycle of these rickettsiae has not been fully elucidated. Given the expanding distribution and growing population of deer species in Portugal, coupled with their direct and indirect interactions with humans during hunting, it becomes crucial to explore their role as sentinels and potential reservoirs of Rickettsia. The present investigation aimed to detect and evaluate exposure to Rickettsia in free-living deer from Portugal. Blood samples (n = 77) were collected from hunted game animals (red deer and fallow deer) from different areas throughout Portugal (Idanha-a-Nova, Monte Fidalgo, Montalvão and Arraiolos) and sera were tested by immunofluorescence assay, to detect antibodies. Additionally, blood DNA samples were screened for SFGR by nested-polymerase chain reaction targeting a fragment of the outer membrane protein B (ompB) gene, as well as for Anaplasma and Ehrlichia spp. targeting the 16S rRNA gene. Thirty-five per cent (25 deer and two fallow deer) tested positive (sera with a titer ≥1:64) for IgG antibodies against Rickettsia conorii. No rickettsial DNA was detected by PCR for the ompB gene, and all DNA samples tested negative for Anaplasma and Ehrlichia. As far as we know, this study is the first screening of cervid species in Portugal for Rickettsia antibodies. The findings suggest that these animals serve as useful sentinel indicators for the circulation of rickettsiae, offering a complementary perspective to studies focused on ticks. The increasing numbers of hunted deer in Portugal and the potential zoonotic features of Rickettsia spp. highlight the importance of continued surveillance directed at tick-borne diseases, especially those involving wild animals.

Tissue-specific localization of tick-borne pathogens in ticks collected from camels in Kenya: insights into vector competence.

Background: Tick-borne pathogen (TBP) surveillance studies often use whole-tick homogenates when inferring tick-pathogen associations. However, localized TBP infections within tick tissues (saliva, hemolymph, salivary glands, and midgut) can inform pathogen transmission mechanisms and are key to disentangling pathogen detection from vector competence. Methods: We screened 278 camel blood samples and 504 tick tissue samples derived from 126 camel ticks sampled in two Kenyan counties (Laikipia and Marsabit) for Anaplasma, Ehrlichia, Coxiella, Rickettsia, Theileria, and Babesia by PCR-HRM analysis. Results: Candidatus Anaplasma camelii infections were common in camels (91%), but absent in all samples from Rhipicephalus pulchellus, Amblyomma gemma, Hyalomma dromedarii, and Hyalomma rufipes ticks. We detected Ehrlichia ruminantium in all tissues of the four tick species, but Rickettsia aeschlimannii was only found in Hy. rufipes (all tissues). Rickettsia africae was highest in Am. gemma (62.5%), mainly in the hemolymph (45%) and less frequently in the midgut (27.5%) and lowest in Rh. pulchellus (29.4%), where midgut and hemolymph detection rates were 17.6% and 11.8%, respectively. Similarly, in Hy. dromedarii, R. africae was mainly detected in the midgut (41.7%) but was absent in the hemolymph. Rickettsia africae was not detected in Hy. rufipes. No Coxiella, Theileria, or Babesia spp. were detected in this study. Conclusions: The tissue-specific localization of R. africae, found mainly in the hemolymph of Am. gemma, is congruent with the role of this tick species as its transmission vector. Thus, occurrence of TBPs in the hemolymph could serve as a predictor of vector competence of TBP transmission, especially in comparison to detection rates in the midgut, from which they must cross tissue barriers to effectively replicate and disseminate across tick tissues. Further studies should focus on exploring the distribution of TBPs within tick tissues to enhance knowledge of TBP epidemiology and to distinguish competent vectors from dead-end hosts.

Prevalence and genetic diversity of Anaplasma and Ehrlichia in ticks and domesticated animals in Suizhou County, Hubei Province, China.

Anaplasma and Ehrlichia are tick-borne bacterial pathogens that cause anaplasmoses and ehrlichioses in humans and animals. In this study, we examined the prevalence of Anaplasma and Ehrlichia species in ticks and domesticated animals in Suizhou County, Hubei Province in the central China. We used PCR amplification and DNA sequencing of the 16S rRNA, groEL, and gltA genes to analyze. We collected 1900 ticks, including 1981 Haemaphysalis longicornis and 9 Rhipicephalus microplus, 159 blood samples of goats (n = 152), cattle (n = 4), and dogs (n = 3) from May to August of 2023. PCR products demonstrated that Anaplasma bovis, Anaplasma capra, and an Ehrlichia species were detected in the H. longicornis with the minimum infection rates (MIR) of 1.11%, 1.32%, and 0.05%, respectively; A. bovis, A. capra, and unnamed Anaplasma sp. were detected in goats with an infection rate of 26.31%, 1.31% and 1.97%, respectively. Anaplasma and Ehrlichia species were not detected from cattle, dogs and R. microplus ticks. The genetic differences in the groEL gene sequences of the Anaplasma in the current study were large, whereas the 16S rRNA and gltA gene sequences were less disparate. This study shows that ticks and goats in Suizhou County, Hubei Province carry multiple Anaplasma species and an Ehrlichia species, with relatively higher infection rate of A. bovis in goats. Our study indicates that multiple Anaplasma and Ehrlichia species exist in ticks and goats in the central China with potential to cause human infection.

Sample-to-answer direct real-time PCR detection of Anaplasma phagocytophilum, Ehrlichia spp., and Babesia spp. infections in whole-blood specimens.

Emerging tick-borne illnesses, such as anaplasmosis, babesiosis, or ehrlichiosis, are caused by obligate intracellular pathogens that have clinically comparable presentations. Diagnostics used in laboratories today are serologic assays and blood smear analyses, which have known diagnostic limits. This study evaluated the performance of a sample-to-answer direct real-time PCR laboratory-developed test for the multiplex qualitative detection of Anaplasma, Babesia, and Ehrlichia DNA in whole-blood specimens. Compared to two standard-of-care (SOC) methods, the DiaSorin tick-borne laboratory-developed test for Anaplasma detection demonstrated a positive percent agreement (PPA) and negative percent agreement (NPA) of 100% (95% CI, 0.80 to 1.0) and 89% (95% CI, 0.74 to 0.97), respectively with a discordant rate of 9.3% against microscopy. After discordant resolution, the NPA increased to 100%. For Babesia, the test demonstrated a PPA of 100% (95% CI, 0.90 to 1.0) and NPA of 100% (95% CI, 0.90 to 1.0). Compared to a SOC PCR method Anaplasma samples showed a PPA of 100% (95% CI, 0.66 to 1.0) and NPA of 100% (95% CI, 0.90 to 1.0). Ehrlichia results showed a PPA of 100% (95% CI, 0.69 to 1.0) and NPA of 100% (95% CI, 0.90 to 1.0). The total percent agreement was 98% (95% CI, 0.95 to 0.99) with a κ statistic of 0.95 (95% CI, 0.90 to 0.99) or almost perfect agreement compared to SOC methods. This laboratory-developed test for detecting Anaplasma, Babesia, and Ehrlichia DNA provides rapid and reliable detection of tick-borne infections without nucleic acid extraction. IMPORTANCE: This work demonstrates that detection of tick-borne illnesses, such as anaplasmosis, babesiosis, or ehrlichiosis, can be performed directly from whole blood with no extraction. The assay described here has a high positive and negative percent agreement with existing methods and is used as the standard of care. An increasing incidence of tick-borne illness combined with shortage of well-trained technologists to perform traditional manual testing, testing options that can be adapted to various lab settings, are of the utmost importance.

Molecular detection and diversity of tick-borne rickettsial pathogens in ticks collected from camel (Camelus dromedarius) in Upper Egypt.

Tick-borne rickettsial pathogens pose significant threats to public and animal health. In Upper Egypt, limited information exists regarding the prevalence and diversity of such tick-borne pathogens. Therefore, this study aimed to conduct a comprehensive investigation to elucidate the presence and variety of tick-borne rickettsial pathogens in Upper Egyptian camels. Our results revealed a prevalence of 2.96 % for Anaplasma marginale and 0.34 % for Candidatus Anaplasma camelii among Hyalomma ticks. However, Ehrlichia spp. weren't detected in our study. The identification of Ca. A. camelii in H. dromedari ticks was documented for the first time, suggesting a potential mode of transmission in camels. Notably, this study marks the first documentation of Rickettsia aeschlimannii with a prevalence of 6.06 % in the study area. Furthermore, we detected Coxiella burnetii in a prevalence of 8.08 % in Hyalomma ticks, indicating a potential risk of Q fever transmission. Molecular techniques results were confirmed by sequencing and phylogenetic analysis and provided valuable insights into the epidemiology of these pathogens, revealing their diversity. This study is vital in understanding tick-borne rickettsial pathogens' prevalence, distribution, and transmission dynamics in Upper Egypt. In conclusion, our findings emphasize the importance of continued research to enhance our understanding of the epidemiology and impact of these pathogens on both animal and human populations.

Infections and Influencing Factors of Pathogens in Rattus norvegicus along the Zengjiang River in Guangzhou, China.

Background: Rattus norvegicus can carry and transmit various zoonotic pathogens. Some studies were conducted to investigate a few zoonotic pathogens in Guangzhou, China, but no coinfections were investigated or specifically mentioned. Studies on the infections and the influencing factors of various zoonotic pathogens in R. norvegicus along the Zengjiang River in Guangzhou have not been carried out. Materials and Methods: In this study, R. norvegicus was captured in November 2020 and September 2021 along the Zengjiang River, and was tested for Bartonella spp., Leptospira spp., Orientia tsutsugamushi, Borrelia burgdorferi, Hantavirus (HV), Ehrlichia spp., and severe fever with thrombocytopenia syndrome virus (SFTSV) by the RT-PCR. Logistic regression analysis was used to determine the impact of habitat and demographic factors on the infections and coinfections of the surveyed pathogens. Results: In 119 R. norvegicus, the detection rates of Bartonella spp., Leptospira spp., O. tsutsugamushi, B. burgdorferi, and HV were 46.2%, 31.9%, 5%, 0.8%, and 18.5%, respectively. Ehrlichia spp. and SFTSV were negative. The triple coinfection rate of Bartonella spp., Leptospira spp., and HV was 11.8%. In addition, the coinfection of Bartonella spp., Leptospira spp., and B. burgdorferi was 0.8%. Dual coinfection of Bartonella spp. and Leptospira spp., Leptospira spp. and HV, Bartonella spp. and O. tsutsugamushi, Leptospira spp. and O. tsutsugamushi, and HV and O. tsutsugamushi was 9.2%, 3.4%, 1.7%, 1.7%, and 0.8%, respectively. Infections of these pathogens in R. norvegicus were found in habitats of banana plantation, grassland, and bush. Weight affected the infection of Bartonella spp., Leptospira spp., or HV in R. norvegicus. Conclusions: R. norvegicus along the Zengjiang River not only carried various potentially zoonotic pathogens but also had a variety of coinfections. Surveillance of the density and pathogens in R. norvegicus should be strengthened to reduce the incidence of relevant zoonotic diseases.

Prevalence of Anaplasma, Ehrlichia and Rickettsia infections in dogs in Iran: A meta-analysis study.

The current study aims to assess the prevalence of different genera of Rickettsiales, intracellular bacteria, in dogs across various regions of Iran. Rickettsiales, as zoonotic pathogens, can have various manifestations in different species, including immunosuppression, anaemia and neuropathy. Due to their close interactions with people and livestock, dogs can serve as reservoirs and transmit these pathogens to humans and other animals. The data from this research can be valuable for managing and controlling related diseases and complications in Iran and possibly neighbouring countries. Pertinent data for this study was gathered without time limitations until 1 March 2022, from different databases. Of all the inspected studies, 26 were eligible based on the inclusion criteria. The Egger test result and asymmetry in the funnel plot revealed significant publication bias; therefore, the meta-analysis model was corrected with the trim-and-fill method. After correction, the prevalence of rickettsial infections among dogs varies by genus - 20.1% for Anaplasma spp. and 10% for Ehrlichia spp. - with an overall prevalence estimated at 18.3% by random-effects analysis. The highest and lowest estimated pooled prevalences were associated with the southwestern (38.5%) and southern (0.3%) provinces of Iran, respectively. The pooled prevalence of rickettsial infection was higher in female dogs (OR = 1.198; p < 0.978; 95% CI, 0.842-1.705) and in dogs ≤2 years (OR = 1.014; p < 0.312; 95% CI, 0.598-1.72), but the difference was not statistically significant. Ultimately, the pooled prevalence of rickettsial infections among dogs is relatively low compared to other countries like Qatar, Iraq, Saudi Arabia and Turkey, which are nearby Iran. Given the significant clinical outcomes of this disease, necessary measures for prevention should be taken.

A canine case of Ehrlichia canis infection without a history of being in an endemic area in Japan.

A mixed-breed, 8-year-old male dog developed neutropenia, thrombocytopenia, and hyperglobulinemia. Bone marrow hyperplasia and splenic plasmacytosis were cytologically observed. The dog had never been outside of Tokyo or Shizuoka Prefecture. Splenectomy was performed to confirm and remove the cause of splenic plasmacytosis. A histopathological diagnosis of splenic plasmacytoma was made; however, serum protein electrophoresis showed polyclonal gammopathy. Further screening was performed, and Ehrlichia canis infection was confirmed. The dog was treated with doxycycline for 5 weeks. After the antibiotic therapy, no relapse of neutropenia, thrombocytopenia, hyperglobulinemia, or positive polymerase chain reaction result of E. canis infection was observed for 3 years. Careful attention should be given to ehrlichiosis when exploring the cause of pancytopenia or hyperglobulinemia, regardless of the travel history.

First molecular survey of tick-borne protozoan and bacterial pathogens in the questing tick population in Bangladesh.

Questing ticks carry various tick-borne pathogens (TBPs) that are responsible for causing tick-borne diseases (TBDs) in humans and animals around the globe, especially in the tropics and sub-tropics. Information on the distribution of ticks and TBPs in a specific geography is crucial for the formulation of mitigation measures against TBDs. Therefore, this study aimed to survey the TBPs in the questing tick population in Bangladesh. A total of 2748 questing hard ticks were collected from the pastures in Sylhet, Bandarban, Sirajganj, Dhaka, and Mymensingh districts through the flagging method. After morphological identification, the ticks were grouped into 142 pools based on their species, sexes, life stages, and collection sites. The genomic DNA extracted from tick specimens was screened for 14 pathogens, namely Babesia bigemina (AMA-1), Babesia bovis (RAP-1), Babesia naoakii (AMA-1), Babesia ovis (18S rRNA), Theileria luwenshuni (18S rRNA), Theileria annulata (Tams-1), Theileria orientalis (MPSP), Anaplasma marginale (groEL), Anaplasma phagocytophilum (16S rRNA), Anaplasma bovis (16S rRNA), Anaplasma platys (16S rRNA), Ehrlichia spp. (16S rRNA), Rickettsia spp. (gltA), and Borrelia (Bo.) spp. (flagellin B) using genus and species-specific polymerase chain reaction (PCR) assays. The prevalence of the detected pathogens was calculated using the maximum likelihood method (MLE) with 95 % confidence interval (CI). Among 2748 ixodid ticks, 2332 (84.86 %) and 416 (15.14 %) were identified as Haemaphysalis bispinosa and Rhipicephalus microplus, respectively. Haemaphysalis bispinosa was found to carry all the seven detected pathogens, while larvae of R. microplus were found to carry only Bo. theileri. Among the TBPs, the highest detection rate was observed in A. bovis (20/142 pools, 0.81 %, CI: 0.51-1.20), followed by T. orientalis (19/142 pools, 0.72 %, CI: 0.44-1.09), T. luwenshuni (9/142 pools, 0.34 %, CI: 0.16-0.62), B. ovis (4/142 pools, 0.15 %, CI: 0.05 - 0.34) and Bo. theileri (4/142 pools, 0.15 %, CI: 0.05-0.34), Ehrlichia ewingii (3/142 pools, 0.11 %, CI: 0.03-0.29), and Babesia bigemina (1/142, 0.04 %, CI: 0.00 - 0.16). This study reports the existence of T. luwenshuni, E. ewingii, and Bo. theileri in Bangladesh for the first time. The novel findings of this study are the foremost documentation of transovarian transmission of B. bigemina and E. ewingii in H. bispinosa and also provide primary molecular evidence on the presence of E. ewingii and Bo. theileri in H. bispinosa. Therefore, this study may shed light on the circulating TBPs in ticks in the natural environment and thereby advocate awareness among physicians and veterinarians to control and prevent TBDs in Bangladesh.