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.

Molecular Evidence of Ehrlichia canis (Rickettsiales: Anaplasmataceae) in Ticks (Ixodida: Ixodidae) Associated with Dogs (Carnivora: Canidae) from Nuevo Leon, Mexico.

Background: Ehrlichia canis is transmitted by ticks causing Canine monocytic ehrlichiosis, which is considered one of the most critical tickborne pathogens. Materials and Methods: This study aimed to identify by PCR technique E. canis in ticks associated with dogs from urban and rural homes in Nuevo Leon, Mexico. The study was conducted at 13 localities in eight municipalities from 2012 to 2021. Results: A total of 1873 ticks of three species were captured: Amblyomma tenellum, Dermacentor variabilis, and Rhipicephalus sanguineus s.l. The overall infection rate of E. canis in ticks was 59.12% (149/252). Of the 15 sequences, three haplotypes were identified. Conclusion: The urban transmission cycle of canine ehrlichiosis is demonstrated, where the potential vector is the tick R. sanguineus s.l.

High prevalence of asymptomatic Anaplasma spp. infection in school-aged children in southeastern Gabon.

OBJECTIVES: The objective of this study was to evaluate the detection rates of asymptomatic Anaplasma spp. and Ehrlichia spp. infections in children in southeastern Gabon. METHODS: We conducted a cross-sectional study among school-aged children in southeastern Gabon between May and June 2021. Blood samples were collected. Anaplasmataceae, Anaplasma spp., and Ehrlichia spp. were detected by microscopy and polymerase chain reaction. RESULTS: Of the 452 blood samples collected, 57.5% (n/N=260/452) of the samples were positive for Anaplasma spp. and/or Ehrlichia spp. by microscopy, 86.9% (n/N=393/452) of the samples were positive for both Anaplasmataceae and Anaplasma spp., and none of the samples were found positive for Ehrlichia spp. PCR was more sensitive and specific than microscopy for detection of Anaplasma spp.. CONCLUSIONS: In our study, a significant number of positive blood samples for Anaplasma spp. were found in school-aged children in southeastern Gabon. Further studies are needed to determine the prevalence of different species of Anaplasma, their pathogenicity, and their transmission patterns.

Clinical and pathological factors associated with Ehrlichia canis in companion dogs.

INTRODUCTION: Canine monocytic ehrlichiosis (CME) is a disease caused by the Gram-negative bacteria Ehrlichia canis, a bacterium that affects domestic dogs but can also infect humans. The diagnosis implies a challenge due to its diversity in clinical manifestations. METHODOLOGY: The frequency of E. canis infection, risk factors, and clinical-pathological parameters associated with seropositivity were calculated with the PROC FREQ TABLES and PROC LOGISTIC procedures of the SAS statistical software. RESULTS: The study showed a seroprevalence of 26.62% (156/586). Association between seropositivity and risk factors was found. The age and the presence of ticks including clinical signs such as anorexia, seizures, cough, petechiae, epistaxis, and hematochezia, as well as multiple blood and biochemical alterations were analyzed. The logistic regression analysis showed a high predictive power (c = 0.98) for CME for thrombocytopenia, leukopenia, and anemia. CONCLUSIONS: The high prevalence of E. canis in endemic areas makes its diagnosis difficult. Thus, clinical signs must be considered, along with blood and biochemical alterations, as a possible predictor of the disease.

Mathematical model of Ehrlichia chaffeensis transmission dynamics in dogs.

Ehrlichia chaffeensis is a tick-borne disease transmitted by ticks to dogs. Few studies have mathematical modelled such tick-borne disease in dogs, and none have developed models that incorporate different ticks' developmental stages (discrete variable) as well as the duration of infection (continuous variable). In this study, we develop and analyze a model that considers these two structural variables using integrated semigroups theory. We address the well-posedness of the model and investigate the existence of steady states. The model exhibits a disease-free equilibrium and an endemic equilibrium. We calculate the reproduction number (T0). We establish a necessary and sufficient condition for the bifurcation of an endemic equilibrium. Specifically, we demonstrate that a bifurcation, either backward or forward, can occur at T0=1, leading to the existence, or not, of an endemic equilibrium even when T0<1. Finally, numerical simulations are employed to illustrate these theoretical findings.

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.

Molecular occurrence and genetic diversity of Ehrlichia canis in naturally infected dogs from Thailand.

Canine monocytic ehrlichiosis is cause by Ehrlichia canis resulting in hematologic disorders and severe clinical signs. The aim of this study was to scrutinize the molecular detection and genetic diversity of E. canis based on the trp36 gene in dogs from Thailand's northern and central regions. A total of 120 dogs blood samples were amplified for trp36 gene of E. canis using the polymerase chain reaction (PCR). Forty-seven out of 120 dog blood samples (39.16%, 47/120) were positive for E. canis the trp36 DNA with 790 bp of PCR amplicon size. The factor significantly associated with E. canis infection is animal housing status (p < 0.05). Sequence and phylogenetic analysis showed that E. canis trp36 gene of Thailand isolates was clustered into 1st clade with similarity ranging from 95.65 to 100% together with the US genogroup. The 14 haplotypes of the trp36 gene shown in TCS network exhibited that haplotype #1-4 was found in Thailand. The entropy analysis of the trp36 gene illustrated 751 polymorphic sites and 271 entropy peaks of nucleic and amino acid sequences, respectively. Hence, these findings are crucial for better understanding the epidemiology of Ehrlichia infection and could be helpful for implementing control measures in Thailand.

Association between vector-borne pathogen seroprevalence in shelter-housed and owned dog populations in the contiguous United States of America.

Domestic dogs are susceptible to numerous vector-borne pathogens that are of significant importance for their health. In addition to being of veterinary importance, many of these pathogens are zoonotic and thus may pose a risk to human health. In the USA, owned dogs are commonly screened for exposure to or infection with several canine vector-borne pathogens. Although the screening data are widely available to show areas where infections are being diagnosed, testing of owned dogs is expected to underestimate the actual prevalence in dogs that have no access to veterinary care. The goal of this study was to measure the association between the widely available data from a perceived low-risk population with temporally and spatially collected data from shelter-housed dog populations. These data were then used to extrapolate the prevalence in dogs that generally lack veterinary care. The focus pathogens included Dirofilaria immitis, Ehrlichia spp., Anaplasma spp., and Borrelia burgdorferi. There was a linear association between the prevalence of selected vector-borne pathogens in shelter-housed and owned dog populations and, generally, the data suggested that prevalence of heartworm (D. immitis) infection and seroprevalence of Ehrlichia spp. and B. burgdorferi are higher in shelter-housed dogs, regardless of their location, compared with the owned population. The seroprevalence of Anaplasma spp. was predicted to be higher in areas that have very low to low seroprevalence, but unexpectedly, in areas of higher seroprevalence within the owned population, the seroprevalence was expected to be lower in the shelter-housed dog population. If shelters and veterinarians make decisions to not screen dogs based on the known seroprevalence of the owned group, they are likely underestimating the risk of exposure. This is especially true for heartworm. With this new estimate of the seroprevalence in shelter-housed dogs throughout the USA, shelters and veterinarians can make evidence-based informed decisions on whether testing and screening for these pathogens is appropriate for their local dog population. This work represents an important step in understanding the relationships in the seroprevalences of vector-borne pathogens between shelter-housed and owned dogs, and provides valuable data on the risk of vector-borne diseases in dogs.

Evaluation of Anaplasma spp. seroprevalence in dogs and association with incidence of human anaplasmosis.

Point-of-care (POC) ELISA tests are routinely used in US veterinary practices to screen canine patients for antibodies to tick-transmitted pathogens. Results are also used to monitor spatial and temporal trends in canine seroprevalence, and these data can build awareness of the risk to humans of tick-transmitted diseases such as Lyme disease and anaplasmosis. This study utilized a second-generation test that has incorporated additional Anaplasma-specific peptides into a commercial POC ELISA test to allow detection of Anaplasma spp. antibodies earlier post-infection. A convenience population consisting of 19,894 canine samples from a US commercial diagnostic laboratory were tested using the second-generation POC ELISA test to describe regional Anaplasma spp. canine seroprevalence and assess correlation to anaplasmosis cases reported to Centers for Disease Control and Prevention by state. Antibodies to Anaplasma spp. were detected in 1646 samples (8.3%) with the Northeast and Midwest US census regions having the highest proportion of positive samples. At the state level, a significant correlation was found between canine Anaplasma spp. seroprevalence and human anaplasmosis incidence (r2 = 0.64). Although estimates of canine Anaplasma spp. seroprevalence presented here using the second-generation POC ELISA are generally increased, especially in the Northeast and Midwest, the regional distribution of canine samples testing positive for Anaplasma spp. antibodies is consistent with previous reports. The observed correlation with human anaplasmosis incidence indicates that results from the second-generation POC ELISA will continue to add value in epidemiological assessment of human anaplasmosis risk.

Canine ehrlichiosis seropositivity and associated factors in Kenya and Tanzania: a retrospective study.

Canine ehrlichiosis is an important tick-borne disease caused by bacteria in the Ehrlichia genus with species such as E. canis, E. ewingii and E. chaffeensis resulting in a severe dog illness. This study determined the occurrence of canine ehrlichiosis antibodies and its associated factors in Kenya and Tanzania. This was a retrospective study that evaluated laboratory records of 400 samples from Kenya and Tanzania submitted to Pathologists Lancet Kenya for the IDEXX SNAP 4Dx™ Plus test between the years 2016 and 2021. Records of all samples submitted to the Pathologists Lancet Kenya veterinary laboratory for the diagnostic tests were retrieved, examined, and compiled. Descriptive statistics and univariable and multivariable logistic regression were considered during analysis. The overall proportion of samples that tested positive for canine ehrlichiosis was 23% (92/400). Samples from Kenya accounted for 61% (245/400) of samples, and the percent positive was 31% (29/245). The samples from Tanzania accounted for 39% (155/400), and the percent positive was 69% (63/155). In the final model, the odds of a sample testing positive was 1.7 times for those submitted from July to December compared with those submitted from January to June. Blood samples of dogs from Tanzania had 5.31 times the odds of testing positive on the SNAP test when compared with those from Kenya. This study reports high percent positive in samples originating from Tanzania and those received during the year's second half.

Detection of Hemopathogens in Chelonoidis carbonaria: Microscopic, Molecular, Hematological, and Clinical Biochemistry Aspects.

Background: The growing contact between men and wild animals, caused by the increase in the population in urban centers and the destruction of the habitat of these animals, has been leading to a greater circulation of pathogens between humans and wildlife. Chelonoidis carbonaria, a tortoise found throughout South America, is one of the animals most rescued from animal trafficking and illegal breeding. Considering this situation, this study aimed to verify the occurrence of hemoparasites in C. carbonaria. Materials and Methods: Blood samples from 73 C. carbonaria were collected from animals located in (1) a rural commercial breeding unit, (2) an urban zoo, and (3) a center of rescued animal screening. Genomic DNA was extracted from these animals and used in PCRs to detect specific genomic fragments of haemogregarines (i.e., Hepatozoon and Hemolivia), and members of the Anaplasmataceae Family (i.e., Ehrlichia sp. and Anaplasma sp.). Blood samples were screened for hemopathogens by direct microscopy and were used for hematological assays, and serum samples were analyzed to determine the concentration of serum components. Results: It was found that 34.2% of the tortoises presented Sauroplasma sp. in their blood samples; these animals showed clinical biochemistry changes that indicate altered liver function. Two zoo animals were positive for Ehrlichia sp. in PCR, and also presented clinical biochemistry and hematological changes. Conclusion: The present project is pioneer in the detection of Ehrlichia sp. in C. carbonaria, and was able to identify changes in clinical biochemistry that can be a result of the infection by hemopathogens in this species.

Molecular Detection of Tick-Borne Pathogens in Dogs from Indigenous Communities, Amazon, Brazil.

Background: There are few reports of tick-borne pathogens infecting dogs living in indigenous communities of Brazil. Herein, we aimed to molecularly detect vector-borne pathogens in dogs from two indigenous communities in the Brazilian Amazon. Materials and Methods: We surveyed 327 dogs raised in Amazon region at 2 distinct indigenous ethnicities for the molecular detection of tick-borne pathogens (114 from Tapirapé and 213 from Karajá indigenous ethnicity). Whole blood samples were subjected to PCR and sequencing for Ehrlichia, Babesia, and Hepatozoon. Univariate and multivariate analyses were used to investigate the factors affecting the pathogen infection patterns in dogs. Results: Among the 327 blood samples, 40 were positive for Ehrlichia canis (12.2%), 2 for Anaplasma platys (0.61%), and 204 were positive for Hepatozoon canis (66.5%). Binary Logistic Regression showed association between E. canis infection and ethnicity (p = 0.010) and tick attachment (p = 0.041). Karajá dogs were 3.4 times (95% CI 1.3-8.5) more likely to be positive for E. canis than Tapirapé dogs. Dogs with ticks were 2.5 times more likely (95% CI 1.0-7.6) to be positive for E. canis than dogs without ticks. Conclusions: Our survey expands the knowledge regarding the presence of vector-borne pathogens in dogs from indigenous communities in the Amazon region.

Capybara density and climatic factors as modulators of Ehrlichia prevalence in questing ticks in the Iberá wetlands, Argentina.

We evaluated the presence of Ehrlichia spp. in unfed capybara ticks, Amblyomma dubitatum, and explored its association with capybaras density, ticks density and environmental variables. We observed that in the Iberá wetlands ecoregion A. dubitatum is infected by "Candidatus Ehrlichia hydrochoerus" and in a lesser extent with an Ehrlichia species closely related to Ehrlichia chaffeensis. The frequency of "Ca. Ehrlichia hydrochoerus" presence in A. dubitatum was not associated with vector abundance, but the probability of finding "Ca. Ehrlichia hydrochoerus"-infected ticks increased when the density of capybaras was low two months before. We hypothesize that when the density of capybaras decreases, A. dubitatum immature stages may seek out alternative hosts one of which could exhibit high realized reservoir competence for "Ca. Ehrlichia hydrochoerus", leading to an increased prevalence of this ehrlichiae in questing A. dubitatum. High minimum temperatures and high cumulative rainfall in the time period previous to tick collection (15 to 60 days) were positively correlated with the prevalence of "Ca. Ehrlichia hydrochoerus" infection in A. dubitatum. Our results suggest that a combination of factors (both biological and abiotic) could raise the risk of human exposure to tick-borne Ehrlichia in the Iberá wetlands ecoregion.

Correlation between canine biochemical analytes and TRP36 ELISA seropositivity for Ehrlichia canis in Brazil.

BACKGROUND: Synthetic peptides of tandem repeat proteins (TRPs) have been employed in the serologic analysis of canine monocytic ehrlichiosis (CME) and used in epidemiological studies in Brazil. Based on molecular studies of TRPs, different genotypes of Ehrlichia canis have been described, but data on their pathogenicity remain unknown. OBJECTIVES: To correlate hepatic, renal, and muscular alterations in relation to different genotypes of E. canis in naturally exposed dogs using enzyme-linked immunosorbent assay (ELISA) with TRP19 and TRP36 synthetic protein antigens. METHODS: Two hundred serum samples were subjected to ELISA with the antigens of TRP19 and three genotypes (US, Br, and CR) of TRP36 of E. canis circulating in Brazil. Positive sera were evaluated through eight biochemical parameters, and the results were evaluated by principal component analysis and canonical correlation. RESULTS: ELISA revealed that 47 (23.5%) serum samples reacted to the BrTRP36 peptide, 36 (18%) reacted to the TRP19 peptide, and 8 (4%) reacted to the USTRP36 and CRTRP36 peptides separately. The most frequent biochemical alterations observed were for CK (59.4%), ALB (31.8%), GLO (28.9%), TP (28.9%), ALP (26%), urea (24.6%), creatinine (14.4%), and ALT (14.4%). The most prominent diagnostic method in canonical correlation analysis was BrTRP36, followed by TRP19, which correlated with hyperglobulinemia and hypoalbuminemia. CONCLUSIONS: Antibodies that reacted against the Brazilian genotype of E. canis correlated positively with hyperglobulinemia and increases in serum urea and creatinine. According to our results, the Brazilian genotype of E. canis is related to the chronic phase of CME.

Under-diagnosis of vector-borne diseases among individuals suspected of having Scrub Typhus in South Korea.

Due to environmental and ecological changes and suitable habitats, the occurrence of vector-borne diseases is increasing. We investigated the seroprevalence of four major vector-borne pathogens in human patients with febrile illness who were clinically suspected of having Scrub Typhus (ST) caused by Orientia tsutsugamushi. A total of 187 samples (182 patient whole blood and sera samples, including 5 follow-up) were collected. Antibodies to Anaplasma phagocytophilum, Ehrlichia chaffeensis, Borrelia burgdorferi, and Bartonella henselae were tested by using indirect immunofluorescence assays. Molecular diagnoses were performed using real-time PCR. Of the 182 cases, 37 (20.3%) cases were designated as confirmed cases of ST, and the remaining 145 (79.7%) cases as other febrile diseases (OFDs). The seroprevalence of A. phagocytophilum, E. chaffeensis, B. burgdorferi, and B. henselae was 51.4% (19/37), 10.8% (4/37), 86.5% (32/37), and 10.8% (4/37) among the ST group, and 42.8% (62/145), 10.4% (19/145), 57.7% (105/145), and 15.9% (29/145) among the OFD group, respectively. There were no significant differences in the seroprevalence between the ST and the OFD groups. Considering the co-occurrence, 89.0% (162/182) had at least one antibody to tick-borne pathogens, 37.0% (60/162) were positive for two pathogens, 17.3% (28/162) for three pathogens, and 6.2% (10/162) for four pathogens. In real-time PCR, O. tsutsugamushi was positive in 16 cases [15 (40.5%) in ST group and 1 (2.2%) in OFD group], and the four other pathogens were negative in all cases except one confirmed as anaplasmosis. In evaluating the five follow-up samples, the appearance of new antibodies or an increase in the pre-existing antibody titers was detected. Our data highlighted that acute febrile illness and manifestations suggestive of a vector-borne infection must be recognized and further considered for coinfections in clinical practice and the laboratory.

Spatial and risk factor analyses of vector-borne pathogens among shelter dogs in the Eastern United States.

BACKGROUND: Vector-borne infections pose significant health risks to humans, domestic animals, and wildlife. Domestic dogs (Canis lupus familiaris) in the United States may be infected with and serve as sentinel hosts for several zoonotic vector-borne pathogens. In this study, we analyzed the geographical distribution, risk factors, and co-infections associated with infection with Ehrlichia spp., Anaplasma spp., Borrelia burgdorferi, and Dirofilaria immitis in shelter dogs in the Eastern United States. METHODS: From 2016 to 2020, blood samples from 3750 shelter dogs from 19 states were examined with IDEXX SNAP® 4Dx® Plus tests to determine the seroprevalence of infection with tick-borne pathogens and infection with D. immitis. We assessed the impact of factors including age, sex, intact status, breed group, and location on infection using logistic regression. RESULTS: The overall seroprevalence of D. immitis was 11.2% (n = 419/3750), the seroprevalence of Anaplasma spp. was 2.4% (n = 90/3750), the seroprevalence of Ehrlichia spp. was 8.0% (n = 299/3750), and the seroprevalence of B. burgdorferi was 8.9% (n = 332/3750). Regional variation in seroprevalence was noted: D. immitis (17.4%, n = 355/2036) and Ehrlichia spp. (10.7%, n = 217/2036) were highest in the Southeast while seroprevalence for B. burgdorferi (19.3%, n = 143/740) and Anaplasma spp. (5.7%, n = 42/740) were highest in the Northeast. Overall, 4.8% (n = 179/3750) of dogs had co-infections, the most common of which were D. immitis/Ehrlichia spp. (1.6%, n = 59/3750), B. burgdorferi/Anaplasma spp. (1.5%, n = 55/3750), and B. burgdorferi/Ehrlichia spp. (1.2%, n = 46/3750). Risk factors significantly influenced infection across the evaluated pathogens were location and breed group. All evaluated risk factors were significant for the seroprevalence of D. immitis antigens. CONCLUSIONS: Our results demonstrate a regionally variable risk of infection with vector-borne pathogens in shelter dogs throughout the Eastern United States, likely due to varying distributions of vectors. However, as many vectors are undergoing range expansions or other changes in distribution associated with climate and landscape change, continued vector-borne pathogen surveillance is important for maintaining reliable risk assessment.

First molecular confirmation of multiple zoonotic vector-borne diseases in pet dogs and cats of Hong Kong SAR.

In recent years, the incidence of vector-borne diseases (VBDs) has increased throughout the globe. In particular, tick-borne diseases (e.g., caused by Ehrlichia canis, E. ewingii, Anaplasma phagocytophilum, A. platys, Borrelia burgdorferi sensu stricto (s.s.) and Babesia gibsoni) and mosquito-borne diseases (e.g., caused by Dirofilaria immitis) diseases pose a burden on animal health. Nevertheless, there have been no studies undertaken on the occurrence of VBDs in pet dogs and cats in Hong Kong SAR. This study fills this gap, and is the first to determine the seroprevalence of major VBDs, such as those caused by D. immitis, E. canis, E. ewingii, A. phagocytophilum, A. platys and B. burgdorferi s.s, in dogs and cats through commercially available SNAP 4Dx plus testing. Infection by all these pathogens and Babesia sp. was further assessed through PCR and DNA sequencing. A total of 224 blood samples were collected from domestic dogs (n = 159) and cats (n = 65) in Hong Kong SAR during summer 2022. Hematocrit and platelet counts were determined in each blood sample and other hematological parameters were assessed using an automatic hematology analyzer and vortex the specimen for one to two minutes at or near the highest setting to minimize the clumping. All cat sera samples were negative for tested pathogens, but antibodies against some of the pathogens were detected in dog sera samples. Here, the highest figures were recorded for seroprevalence of E. canis/E. ewingii (10.7%), followed by D. immitis (5.7%), and A. phagocytophilum/A. platys (2.5%). No B. burgdorferi s.s. antibodies were detected in any of the dogs tested. Through molecular diagnostics, we detected the presence of B. gibsoni (3.7%), E. canis (3.1%), D. immitis (5.7%), and A. phagocytophilum (1.3%). Neighbor-Joining phylogenetic trees for vector-borne pathogens (i.e., genus Anaplasma sp.) showed 100% clustering to Japan, the USA and Germany, whereas genus Ehrlichia sp. showed 100% clustering to China, Turkey, Cuba, and Greece. Similarly, genus Babesia sp. clustered 100% to India, Sri Lanka and Austria, while D. immitis clustered in Iraq, South Korea, Portugal, France, the USA and Italy. This study provides the first evidence on the occurrence of tick-borne pathogens in pet dogs in Hong Kong SAR. Based on these findings, it is recommended that appropriate screening should be undertaken in domestic dogs to evaluate the prevalence of these pathogens and promote the timely control of VBDs.

Emergence of ehrlichiosis by a new tick-borne Ehrlichia species in China.

OBJECTIVES: From March to June 2021, the reported number of clinically diagnosed endemic typhus in Anhui and Hubei provinces of China nearly increased four-fold compared with the monthly average numbers in last 5 years. An etiological and epidemiological investigation was initiated. METHODS: The clinical specimens from the reported patients and the potential vector ticks were collected for molecular and serological detection, as well as cell culturing assay to identify the potential pathogen. RESULTS: Polymerase chain reaction and sequence analysis of rrs and groEL showed that the pathogen from these patients was Ehrlichia sp., isolated from Haemaphysalis longicornis attached to these patients. The phylogenetic analysis based on 39 Ehrlichia genomes suggested that it should be taxonomically classified as a novel species, tentatively named "Candidatus Ehrlichia erythraense". A total of 19 of 106 cases were confirmed as Candidatus Ehrlichia erythraense infections by polymerase chain reaction, sequencing, and/or serological tests. The most frequent symptoms were fever (100%), rashes (100%), asthenia (100%), anorexia (100%), and myalgia (79%). CONCLUSION: The occurrence of the disease presenting with fever and rashes in Anhui and Hubei provinces was caused by a novel species of the genus Ehrlichia; physicians need to be aware of this newly-discovered pathogen to ensure appropriate testing, treatment, and regional surveillance.

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

OBJECTIVES: To report the presence of tick-borne diseases in dogs living in the United Kingdom. MATERIALS AND METHODS: Dogs with a final diagnosis of tick-borne diseases made between January 2005 and August 2019 at seven referral institutions in the United Kingdom were included in the study. RESULTS: Seventy-six dogs were included: 25 were diagnosed with ehrlichiosis, 23 with babesiosis, eight with Lyme borreliosis and six with anaplasmosis. Fourteen dogs had co-infections with two or three pathogens. Except for those dogs with anaplasmosis and Lyme borreliosis, most dogs with tick-borne diseases had a history of travel to or from endemic countries. However, three dogs with ehrlichiosis, and one dog each infected with Babesia canis and Babesia vulpes did not have any history of travel. A variety of non-specific clinical signs and laboratory abnormalities were reported. Targeted treatment was successful at achieving clinical remission in 64 (84%) dogs. CLINICAL SIGNIFICANCE: Even in non-endemic areas, veterinary surgeons should consider tick-borne diseases in dogs with compatible clinical presentation and laboratory findings and especially where there is a history of travel. As autochthonous transmission of tick-borne-pathogens does occur, an absence of travel should not rule out tick-borne diseases. Specific diagnostic testing is required to confirm infection, and this enables prompt targeted treatment and often a positive outcome.

Worldwide meta-analysis on Anaplasma phagocytophilum infections in animal reservoirs: Prevalence, distribution and reservoir diversity.

A wide range of vertebrate species are competent reservoirs of Anaplasma phagocytophilum, where the pathogen is maintained in the enzootic cycle and transmitted to humans through activities of tick vectors. An insight into the role and diversity of these reservoirs is vital in understanding the epidemiology of this pathogen. Here, we determined the prevalence, distribution and reservoir diversity of A. phagocytophilum using a systematic review and meta-analysis. Data pooling was performed by the random-effects model, heterogeneity was assessed by the Cochran's Q-test and publication bias by Egger's regression test. Eighty-nine studies from 33 countries across 5 continents revealed A. phagocytophilum pooled prevalence of 15.18% (95% CI: 11.64, 19.57). Continental estimates varied significantly (p < 0.0001), with a range of 2.88% (95% CI: 0.25, 26.20) in South America to 19.91% (95% CI: 13.57, 28.24) in Europe. Country-based estimates ranged between 2.93% (95% CI: 1.17, 7.16) in Slovakia and 71.58% (95% CI: 25.91, 94.77) in Norway. Studies on A. phagocytophilum were concentrated in Europe (51.69%; 46/89) by continent and the USA (22.47%; 20/89) by country. Prevalence in wildlife (17.64%; 95% CI: 12.21-28.59) was significantly higher (p < 0.001) than that among domestic animals (10.68%; 95% CI: 6.61-16.83). Diverse species of wildlife, domestic animals and birds were infected by A. phagocytophilum. To curtail the public health, veterinary and economic consequences of A. phagocytophilum infections, we recommend an all-inclusive epidemiological approach that targets the human, animal and environmental components of the disease.