Candidatus Neoehrlichia mikurensis Infection in Patient with Antecedent Hematologic Neoplasm, Spain1.

We report a confirmed case of Candidatus Neoehrlichia mikurensis infection in a woman in Spain who had a previous hematologic malignancy. Candidatus N. mikurensis infections should be especially suspected in immunocompromised patients who exhibit persistent fever and venous thrombosis, particularly if they live in environments where ticks are prevalent.

Neoehrlichiosis in Symptomatic Immunocompetent Child, South Africa.

We describe a case of neoehrlichiosis in an immunocompetent child with acute febrile illness in South Africa. Neoehrlichiosis was diagnosed by PCR on 16S rDNA from bone marrow aspirate. Phylogenetic analysis indicated an organism closely related to Candidatus Neoehrlichia. Clinicians should be aware of possible ehrlichiosis even in immunocompetent patients.

Infection with Neoehrlichia mikurensis promotes the development of malignant B-cell lymphomas.

The tick-borne pathogen Neoehrlichia (N.) mikurensis is implicated in persistent infection of the vascular endothelium. B cells are crucial for the host defence to this infection. Chronic stimulation of B cells may result in B-cell transformation and lymphoma. Five patients with malignant B-cell lymphoma and concomitant N. mikurensis infection were investigated regarding clinical picture, lymphoma subtype, B-cell lymphoma immunophenotype and IGHV (variable region of the immunoglobulin heavy) gene repertoire. Three of the five patients improved markedly and ceased lymphoma treatment after doxycycline treatment to eliminate N. mikurensis. Sequencing the B-cell lymphoma IGHV genes revealed preferred usage of the IGHV1 (IGHV1-2, and -69) and IGHV3 (IGHV3-15, -21, -23) families. In conclusion, N. mikurensis infection may drive the development of malignant B-cell lymphomas. Eradication of the pathogen appears to induce remission with apparent curing of the lymphoma in some cases.

Neoehrlichia mikurensis-An emerging opportunistic tick-borne infection in immunosuppressed patients.

BACKGROUND: Neoehrlichia mikurensis (N. mikurensis) is a newly discovered tick-borne pathogen that can inflict life-threatening illness in immunocompromised patients. N. mikurensis infection is only detectable by polymerase chain reaction (PCR)-based methodologies. We describe three distinct clinical manifestations of N. mikurensis infection (neoehrlichiosis) in Danish patients receiving B-lymphocyte-depleting therapy, rituximab, for underlying hematological, rheumatological, or neurological disorders. All three patients went through a protracted pre-diagnostic period. METHODS: N. mikurensis DNA was detected and confirmed using two methods. Blood was tested by specific real-time PCR targeting the groEL gene and by 16S and 18S profiling followed by sequencing. Bone marrow was analyzed by 16S and 18S profiling. RESULTS: N. mikurensis was detected in blood samples in all three cases and in bone marrow from one of the three. The severity of the symptoms ranged from prolonged fever lasting more than 6 months to life-threatening hyperinflammation in the form of hemophagocytic lymphohistiocytosis (HLH). Interestingly, all patients presented with splenomegaly and two with hepatomegaly. After starting doxycycline therapy, symptoms were relieved within a few days, and biochemistry and organomegaly quickly normalized. CONCLUSION: We present three Danish patients recognized by the same clinician over a period of 6 months, strongly suggesting that many cases are going unrecognized. Second, we describe the first case of N. mikurensis-induced HLH and emphasize the potential severity of undetected neoehrlichiosis.

Neoehrlichia mikurensis in Danish immunocompromised patients: a retrospective cohort study.

BACKGROUND: The tick-borne bacterium, Neoehrlichia mikurensis (N. mikurensis) can cause severe febrile illness and thromboembolic complications in immunocompromised individuals. We investigated the presence of N. mikurensis DNA in retrospectively collected plasma from a well-characterized cohort of Danish immunocompromised patients. METHODS: Plasma samples from 239 patients with immune dysfunction related to hematological or rheumatological disease or due to immunosuppressive therapy, were retrieved from a transdisciplinary biobank (PERSIMUNE) at Rigshospitalet, Copenhagen, Denmark. Serving as immunocompetent controls, plasma samples from 192 blood donors were included. All samples were collected between 2015 and 2019. Real-time PCR targeting the groEL gene was used to detect N. mikurensis DNA. Sequencing was used for confirmation. Borrelia burgdorferi sensu lato IgG antibodies were detected by ELISA as a proxy of tick exposure. Prevalence was compared using Fisher's exact test. RESULTS: Neoehrlichia mikurensis DNA was detected in 3/239 (1.3%, 95% confidence interval (CI): 0.3 - 3.6%) patients, all of whom primarily had a hematological disease. Follow-up samples of these patients were negative. N. mikurensis DNA was not detected in any of the blood donor samples. IgG antibodies against B. burgdorferi s.l. were detected with similar prevalence in immunocompromised patients and blood donors, i.e., 18/239 (7.5%, 95% CI: 4.8-11.5%) and 11/192 (5.7%, 95%: CI 3.2-10.0%). CONCLUSION: In this study, patients with N. mikurensis were not identified by clinical indication and N. mikurensis may therefore be underdiagnosed in Danish patients. Further investigations are needed to explore the clinical significance and implications of this infection.

Diagnosis of Potomac horse fever (syn. equine neorickettsiosis) in 2 foals in southwestern Ontario.

Potomac horse fever (PHF) is characterized by fever, depression, anorexia, ileus, diarrhea, and occasionally, laminitis. The disease is caused by infection with Neorickettsia risticii and/or N. findlayensis. Equids of all ages may be affected; however, the condition has not been well-characterized in foals. This report describes clinical signs, laboratory findings, and treatment of 2 foals diagnosed with PHF in southwestern Ontario. Feces submitted for an equine PCR panel tested positive for Neorickettsia spp. and were subsequently confirmed to be N. risticii (Case 1) and N. findlayensis (Case 2). Both foals recovered following hospitalization and intensive care. Key clinical message: The purpose of this report is to make veterinarians aware that foals may develop PHF. During summer (July to September), when encountering foals in endemic areas with clinical signs compatible with PHF, veterinarians should consider PHF as a diagnostic rule-out. For confirmation of the diagnosis, blood and feces should be submitted for PCR testing for Neorickettsia spp.

Diagnostic de la fièvre équine du Potomac (syn. néorickettsiose équine) chez 2 poulains dans le sud-ouest de l'Ontario. La fièvre équine du Potomac (PHF) se caractérise par de la fièvre, une dépression, de l'anorexie, un iléus, de la diarrhée et, occasionnellement, une fourbure. La maladie est causée par une infection par Neorickettsia risticii et/ou N. findlayensis. Les équidés de tous âges peuvent être atteints; cependant, cette pathologie n'a pas été bien caractérisée chez les poulains. Ce rapport décrit les signes cliniques, les résultats de laboratoire et le traitement de 2 poulains diagnostiqués avec PHF dans le sud-ouest de l'Ontario. Les matières fécales soumises à un panel PCR équin se sont révélées positives pour Neorickettsia spp. et ont ensuite été confirmées comme étant positives pour N. risticii (cas 1) et N. findlayensis (cas 2). Les deux poulains se sont rétablis après une hospitalisation et des soins intensifs.Message clinique clé :Le but de ce rapport est de sensibiliser les vétérinaires au fait que les poulains peuvent développer une PHF. Pendant l'été (juillet à septembre), lorsqu'ils rencontrent des poulains dans des zones d'endémie présentant des signes cliniques compatibles avec le PHF, les vétérinaires doivent considérer le PHF comme une exclusion diagnostique. Pour confirmer le diagnostic, du sang et des selles doivent être soumis à un test PCR pour Neorickettsia spp.(Traduit par Dr Serge Messier).

Potomac Horse Fever.

Potomac horse fever (PHF) is a common cause of equine colitis in endemic areas. Until recently, the only causative agent known to cause PHF was Neorickettsia risticii. However, N. findlayensis has been isolated from affected horses. Horses typically become infected upon ingestion of Neorickettsia spp.-infected trematodes within aquatic insects. The most common clinical signs include diarrhea, fever, anorexia, lethargy and colic. The diagnostic test of choice for PHF is PCR of blood and feces. Tetracyclines remain an effective treatment. Supportive care, including fluid therapy, colloid administration, NSAID and anti-endotoxin medication, and digital cryotherapy, is also necessary in some cases.

Real-Time PCR Differential Detection of Neorickettsia findlayensis and N. risticii in Cases of Potomac Horse Fever.

Potomac horse fever (PHF) is an acute and potentially fatal enterotyphlocolitis of horses with clinical signs that include anorexia, fever, diarrhea, and laminitis. Its incidence is increasing despite a commercially available vaccine. PHF is caused by Neorickettsia risticii, and the recently rediscovered and classified N. findlayensis. PHF diagnosis is currently accomplished using serology or nested PCR. However, both methods cannot distinguish the two Neorickettsia species that cause PHF. Further, the current N. risticii real-time PCR test fails to detect N. findlayensis. Thus, in this study, two Neorickettsia species-specific real-time PCR assays based on Neorickettsia ssa2 and a Neorickettsia genus-specific real-time PCR assay based on Neorickettsia 16S rRNA gene were developed. The ssa2 real-time PCR tests differentiated N. findlayensis from N. risticii in the field samples for which infection with either species had been verified using multiple other molecular tests and culture isolation, and the 16S rRNA gene real-time PCR detected both Neorickettsia species in the samples. These tests were applied to new field culture isolates from three Canadian provinces (Alberta, Quebec, Ontario) and Ohio as well as archival DNA samples from suspected PHF cases to estimate the prevalence of N. findlayensis in different geographic regions. The results suggest that N. findlayensis frequently causes PHF in horses in Alberta and Quebec. The development of these tests will allow rapid, sensitive, and specific diagnosis of horses presenting with clinical signs of PHF. These tests will also enable rapid and targeted treatment and help develop broad-spectrum vaccines for PHF.

Cytokine responses of immunosuppressed and immunocompetent patients with Neoehrlichia mikurensis infection.

PURPOSE: The tick-borne bacterium Neoehrlichia mikurensis causes the infectious disease neoehrlichiosis in humans. Vascular endothelium is one of the target cells of the infection. Neoehrlichiosis patients with compromised B cell immunity present with more severe inflammation than immunocompetent patients. The aim of this study was to compare the cytokine profiles of immunocompetent and immunosuppressed patients with neoehrlichiosis. METHODS: Blood samples from Swedish and Norwegian immunosuppressed (N = 30) and immunocompetent (N = 16) patients with neoehrlichiosis were analyzed for the levels of 30 cytokines, using a multiplex cytokine assay and ELISA. A gender-matched healthy control group (N = 14) was analyzed in parallel. Data were analyzed using the multivariate method OPLS-DA. RESULTS: The multiplex cytokine analyses generated more cytokine results than did the uniplex ELISA analyses. Multivariate analysis of the multiplex cytokine results established that increased levels of FGF2, GM-CSF, CXCL10, and IFN-γ were associated with immunosuppressed patients, whereas increased levels of IL-15 and VEGF were associated with immunocompetent neoehrlichiosis patients. When multivariate analysis findings were confirmed with uniplex ELISA, it was found that both groups of patients had similarly elevated levels of VEGF, FGF2 and IFN-γ. In contrast, the immunosuppressed patients had clearly elevated levels of CXCL10, CXCL13 and BAFF, whereas the immunocompetent patients had the same levels as healthy controls. CONCLUSION: Pro-angiogenic and type 1 cytokines were produced as part of the host response of neoehrlichiosis independent of immune status, whereas immunosuppressed neoehrlichiosis patients produced cytokines required for B cell-mediated defense.

[Neoehrlichiosis as a cause of feaver of unknown origin]. / Neoehrlichiose als Ursache eines Fiebers unklarer Genese.

Establishing a diagnosis in cases of fever of unknown origin (FUO) in immunocompromised patients can be difficult. In 25-35% infectious diseases are the underlying cause. This article reports the case of a 74-year-old woman with a 5-month history of fever. Through open biopsy of the femoral shaft and microbiological analysis, a diagnosis of neoehrlichiosis could be established. After initiation of treatment with doxycycline, the symptoms quickly resolved resulting in a complete recovery.

Vasculitis due to Candidatus Neoehrlichia mikurensis: A Cohort Study of 40 Swedish Patients.

BACKGROUND: Candidatus (Ca.) Neoehrlichia (N.) mikurensis is an emerging tick-borne pathogen of humans that is closely related to Ehrlichia and Anaplasma species. This strict intracellular bacterium escapes detection by routine microbiologic diagnostic methods such as blood culture, leading to considerable under-diagnosis of the infectious disease it causes, neoehrlichiosis. METHODS: Here, we describe the vascular and thromboembolic events afflicting a series of 40 patients diagnosed with neoehrlichiosis in Sweden during a 10-year period (2009-2019). RESULTS: The majority of the patients (60%) developed vascular events ranging from repeated thrombophlebitis, deep vein thrombosis, pulmonary embolism, transitory ischemic attacks, to arteritis. Younger age was a risk factor for vascular complications. In contrast, there was no difference in the incidence of vascular events between immunosuppressed and immunocompetent patients. However, there were qualitative differences, such that deep vein thrombosis exclusively afflicted the immunosuppressed patients, whereas arteritis was restricted to the immunocompetent persons. We also present the case histories of two patients who developed vasculitis mimicking polyarteritis nodosa and giant cell arteritis. Both were cured by doxycycline treatment. CONCLUSIONS: Ca. N. mikurensis infection should be considered in patients living in tick-endemic areas of Europe and northern Asia who present with atypical vascular and/or thromboembolic events. Early diagnosis and antibiotics targeting this emerging infectious agent can eradicate the infection and prevent the development of new vascular events.

Case report: first symptomatic Candidatus Neoehrlichia mikurensis infection in Slovenia.

BACKGROUND: Candidatus Neoehrlichia mikurensis (CNM) is an emerging tick-born pathogen and usually causes symptomatic infection only in immunocompromised patients. Apart from one described case found in the literature where cultivation was successful, all cases so far were diagnosed by using broad-range 16S rDNA PCR. CASE PRESENTATION: Our patient presented with a prolonged febrile state of unknown origin. Clinical presentation, extensive medical workup and classic microbiologic testing were non-conclusive. Several infectious agents and other causes for the febrile state were excluded. In the end, a broad-range 16S rDNA PCR was to be performed to confirm the diagnosis of CNM infection. Treatment was successful with doxycycline. CONCLUSIONS: Due to the obscurity of the pathogen, diagnostic workup in CNM is prolonged and challenging. More awareness is need about this emerging infectious disease in countries with high prevalence of tick-borne diseases as standard microbiological methods are not successful in confirming the diagnosis.

Potomac horse fever in Ontario: Clinical, geographic, and diagnostic aspects.

Clinical findings, geographic locations, laboratory diagnoses, and culture isolation of Neorickettsia spp. in Potomac horse fever (PHF) cases diagnosed in Ontario between 2015 and 2019 are described. Forty-six confirmed PHF cases occurred from late June to early September. Of 41 horses admitted to the Ontario Veterinary College, 28 (68%) survived and 13 (32%) were euthanized due to poor prognosis or financial constraints. Most cases were in southern Ontario along the Canada-USA border. Blood and fecal samples from 43 suspect PHF cases were submitted to 2 laboratories for polymerase chain reaction (PCR) testing for Neorickettsia risticii. Agreement between both laboratories for detection of N. risticii DNA was excellent for feces [κ = 0.932, 95% confidence interval (CI): 0.80 to 1], and fair for blood samples (κ = 0.494, 95% CI: 0.13 to 0.85). Neorickettia spp. were isolated from 16 of 41 (39%) blood samples. DNA analysis confirmed 14 isolates were N. risticii and 2 were N. findlayensis, a novel species of Neorickettsia recently demonstrated to cause PHF.

La fièvre équine du Potomac en Ontario : aspects cliniques, géographiques et diagnostiques. Les résultats cliniques, emplacements géographiques, diagnostics de laboratoire et isolement par culture de Neorickettsia spp. dans les cas de fièvre équine du Potomac (PHF) diagnostiqués en Ontario entre 2015 et 2019 sont décrits. Quarante-six cas confirmés de PHF sont survenus de la fin juin au début septembre. Sur 41 chevaux admis au Ontario Veterinary College, 28 (68%) ont survécu et 13 (32%) ont été euthanasiés en raison d'un mauvais pronostic ou de contraintes financières. La plupart des cas se trouvaient dans le sud de l'Ontario, le long de la frontière canado-américaine. Des échantillons de sang et de matières fécales provenant de 43 cas suspects de PHF ont été soumis à deux laboratoires pour des tests de réaction d'amplification en chaîne par la polymérase (PCR) pour Neorickettsia risticii. La concordance entre les deux laboratoires pour la détection de l'ADN de N. risticii était excellente pour les selles [κ = 0,932, intervalle de confiance (IC) à 95% : 0,80 à 1] et passable pour les échantillons sanguins (κ = 0,494, IC à 95% : 0,13 à 0,85). Neorickettia spp. ont été isolés à partir de 16 des 41 échantillons de sang (39%). L'analyse de l'ADN a confirmé que 14 isolats étaient N. risticii et deux étaient N. findlayensis, une nouvelle espèce de Neorickettsia récemment démontrée comme causant le PHF.(Traduit par Dr Serge Messier).

An immunosuppressed woman in her seventies with night sweats and weight loss. / En immunsupprimert kvinne i 70-årene med nattesvette og vekttap.

BACKGROUND: Candidatus Neoehrlichia mikurensis is an emerging tick-borne pathogen with widespread distribution in Ixodes ricinus ticks in Europe and Asia. It has been found to cause chronic infections, particularly in immunosuppressed individuals. Common symptoms include relapsing fever, night sweats and thromboembolic episodes, likely due to endovascular infection. CASE PRESENTATION: A patient in her seventies developed persistent night sweats and moderate weight loss that persisted for four months prior to evaluation. There was no history of fever or organ-specific symptoms. Prior diseases included a ten-year history of rheumatoid arthritis treated with rituximab. Initial workup revealed moderately increased acute phase reactants, but no evidence of malignant disease or endocrine abnormalities. Night sweats persisted, and after eight months moderate splenic enlargement was observed. PCR revealed presence of Candidatus Neoehrlichia mikurensis DNA, and symptoms resolved promptly after initiation of oral doxycycline treatment. INTERPRETATION: Infection with anaplasmataceae such as Candidatus Neoehrlichia mikurensis can present with non-specific constitutive symptoms. In this case, persistent night sweats and moderate weight loss were the only manifestations over an eight-month period. Diagnosis is readily established by PCR analysis of whole blood, but a high degree of suspicion and careful assessment of potential exposure is required for timely diagnosis.

A Novel Neorickettsial Infection in 3 Dogs in the Pacific Northwest.

The genus Neorickettsia includes obligate, intracellular bacteria responsible for diseases including Potomac horse fever caused by Neorickettsia risticii and salmon poisoning disease (SPD) caused by Neorickettsia helminthoeca. The Stellanchasmus falcatus (SF) agent is a member of this genus previously associated only with mild clinical signs in dogs. Between 2013 and 2016, 3 dogs in Washington State (USA) presented with disease suggestive of SPD, but N. helminthoeca was not detected by molecular techniques. Clinical signs included depression, anorexia, and diarrhea. Cytologic examination of aspirates supported a diagnosis of granulomatous lymphadenitis with organisms suggestive of Neorickettsia. Dogs either died or were humanely euthanized due to poor response to therapy. Necropsy findings included lymphadenomegaly and hepatomegaly. Histopathology identified granulomatous and lymphoplasmacytic splenitis, lymphadenitis, enteritis, and hepatitis with extensive necrosis. Neorickettsia DNA was detected using genus-specific primers and direct sequencing showed 100% sequence identity to the SF agent in all 3 dogs. This is the first clinicopathologic description of severe disease in dogs attributed to the SF agent. These findings may suggest the emergence of a novel neorickettsial disease in the Pacific Northwest.

Medfly-Wolbachia symbiosis: genotype x genotype interactions determine host's life history traits under mass rearing conditions.

BACKGROUND: Wolbachia pipientis is a widespread, obligatory intracellular and maternally inherited bacterium, that induces a wide range of reproductive alterations to its hosts. Cytoplasmic Incompatibility (CI) is causing embryonic lethality, the most common of them. Despite that Wolbachia-borne sterility has been proposed as an environmental friendly pest control method (Incompatible Insect Technique, IIT) since 1970s, the fact that Wolbachia modifies important fitness components of its hosts sets severe barriers to IIT implementation. Mass rearing of Mediterranean fruit fly, Ceratitis capitata (medfly), is highly optimized given that this pest is a model species regarding the implementation of another sterility based pest control method, the Sterile Insect Technique (SIT). We used the medfly-Wolbachia symbiotic association, as a model system, to study the effect of two different Wolbachia strains, on the life history traits of 2 C. capitata lines with different genomic background. RESULTS: Wolbachia effects are regulated by both C. capitata genetic background and the Wolbachia strain. Wolbachia infection reduces fertility rates in both C. capitata genetic backgrounds and shortens the pre-pupa developmental duration in the GSS strain. On the other hand, regardless of the strain of Wolbachia (wCer2, wCer4) infection does not affect either the sex ratio or the longevity of adults. wCer4 infection imposed a reduction in females' fecundity but wCer2 did not. Male mating competitiveness, adults flight ability and longevity under water and food deprivation were affected by both the genetic background of medfly and the strain of Wolbachia (genotype by genotype interaction). CONCLUSION: Wolbachia infection could alter important life history traits of mass-reared C. capitata lines and therefore the response of each genotype on the Wolbachia infection should be considered toward ensuring the productivity of the Wolbachia-infected insects under mass-rearing conditions.

Assessing bat droppings and predatory bird pellets for vector-borne bacteria: molecular evidence of bat-associated Neorickettsia sp. in Europe.

In Europe, several species of bats, owls and kestrels exemplify highly urbanised, flying vertebrates, which may get close to humans or domestic animals. Bat droppings and bird pellets may have epidemiological, as well as diagnostic significance from the point of view of pathogens. In this work 221 bat faecal and 118 bird pellet samples were screened for a broad range of vector-borne bacteria using PCR-based methods. Rickettsia DNA was detected in 13 bat faecal DNA extracts, including the sequence of a rickettsial insect endosymbiont, a novel Rickettsia genotype and Rickettsia helvetica. Faecal samples of the pond bat (Myotis dasycneme) were positive for a Neorickettsia sp. and for haemoplasmas of the haemofelis group. In addition, two bird pellets (collected from a Long-eared Owl, Asio otus, and from a Common Kestrel, Falco tinnunculus) contained the DNA of a Rickettsia sp. and Anaplasma phagocytophilum, respectively. In both of these bird pellets the bones of Microtus arvalis were identified. All samples were negative for Borrelia burgdorferi s.l., Francisella tularensis, Coxiella burnetii and Chlamydiales. In conclusion, bats were shown to pass rickettsia and haemoplasma DNA in their faeces. Molecular evidence is provided for the presence of Neorickettsia sp. in bat faeces in Europe. In the evaluated regions bat faeces and owl/kestrel pellets do not appear to pose epidemiological risk from the point of view of F. tularensis, C. burnetii and Chlamydiales. Testing of bird pellets may provide an alternative approach to trapping for assessing the local occurrence of vector-borne bacteria in small mammals.

Detection of Anaplasmataceae agents and co-infection with other tick-borne protozoa in dogs and Rhipicephalus sanguineus sensu lato ticks.

Anaplasmosis and ehrlichiosis are of serious health concern worldwide for animals and humans. In the present study, we report the occurrence of Anaplasma platys and Ehrlichia canis in dogs and Rhipicephalus sanguineus sensu lato (s.l.) ticks from Peninsular Malaysia using a nested polymerase chain reaction assay based on amplification of the 16S rRNA gene. Anaplasma platys was detected from dogs and ticks with prevalence rates of 3.3% (8/240) and 2.9% (4/140), respectively. On the other hand, 12.9% (31/240) of the dogs and 0.7% (1/140) of the ticks were tested positive for E. canis. Additionally, co-infections of A. platys and E. canis with Babesia or Hepatozoon protozoa were also noted in this study. Double infection (E. canis + B. gibsoni) was observed in tick, whereas triple infections (E. canis + A. platys + B. vogeli and E. canis + A. platys + H. canis) were found in dogs. This study represents the first evidence of A. platys DNA in R. sanguineus s.l. in Malaysia.

IMMUNOHISTOCHEMICAL AND MOLECULAR EVIDENCE OF PUTATIVE NEORICKETTSIA INFECTION IN COATIS ( NASUA NASUA) FROM SOUTHERN BRAZIL.

The pathologic, molecular, and immunohistochemical findings associated with Neorickettsia helminthoeca are described in coatis ( Nasua nasua). Tissue sections (small intestine, lungs, kidney, liver, and spleen) of coatis ( n = 3) that died at the Bela Vista Biological Refuge, Foz do Iguaçu, Paraná, southern Brazil were routinely processed from histopathology. Selected formalin-fixed paraffin-embedded (FFPE) tissue sections of the small intestine, lungs, and spleen were used in an immunohistochemical (IHC) assay designed to identify the antigens of N. helminthoeca. Additionally, FFPE tissue sections of the small intestine were used to demonstrate antigens of canine parvovirus-2 (CPV-2) by IHC. Histopathology revealed chronic enteritis in all coatis. Parasitic enteritis was diagnosed in two coatis; one of these contained examples of a trematode within the lumen of the small intestine and the ovum of a trematode encysted in the intestinal mucosa. Other significant pathologic findings included interstitial pneumonia ( n = 2) and pyogranulomatous splenitis ( n = 1). Positive immunolabeling for N. helminthoeca was identified within macrophages of the small intestine and reticuloendothelial cells within the germinal centers of the spleen of all coatis; the intestinal trematode was N. helminthoeca IHC-positive. All pulmonary sections revealed negative immunolabeling for N. helminthoeca. Furthermore, the antigens of CPV-2 were not identified in the intestine of any coati. These findings indicate that these coatis were infected by N. helminthoeca, but since clinical and gross pathological findings were not recorded, it is uncertain if this pathogen produced clinical disease in this canid host; therefore, coatis may be asymptomatic or dead-end hosts for this organism.

Anaplasmataceae agents among wild mammals and ectoparasites in Brazil.

Anaplasmataceae agents comprise obligate intracellular bacteria that can cause disease in humans and animals. Between August 2013 and March 2015, 31 Nasua nasua (coati), 78 Cerdocyon thous (crab-eating fox), seven Leopardus pardalis (ocelot), 110 wild rodents, 30 marsupials, and 42 dogs were sampled in the Pantanal wetland, Brazil. In addition, ectoparasites found parasitizing the animals were collected and identified. The present work aimed to investigate the occurrence of Anaplasmataceae agents in wild mammals, domestic dogs and ectoparasites, by molecular and serological techniques. Overall, 14 (17·9%) C. thous, seven (16·6%) dogs and one (3·2%) N. nasua were seroreactive to Ehrlichia canis. Nine dogs, two C. thous, one N. nasua, eight wild rodents, five marsupials, eight Amblyomma sculptum, four Amblyomma parvum, 13 A. sculptum nymphal pools, two Amblyomma larvae pools and one Polygenis (Polygenis) bohlsi bohlsi flea pool were positive for Ehrlichia spp. closely related to E. canis. Seven N. nasua, two dogs, one C. thous, one L. pardalis, four wild rodents, three marsupials, 15 A. sculptum, two Amblyomma ovale, two A. parvum and one Amblyomma spp. larval pools were positive for Anaplasma spp. closely related to A. phagocytophilum or A. bovis. The present study provided evidence that wild animals from Brazilian Pantanal are exposed to Anaplasmataceae agents.