Background Rickettsia bacteria are responsible for diseases in humans and animals around the world, however few details are available regarding its ecology and circulation among wild animals and human populations at high transmission risk in Brazil. The aim of this study was to investigate the occurrence of ticks and Rickettsia spp. in wild boars, corresponding hunting dogs and hunters. Methods Serum samples and ticks were collected from 80 free-range wild boars, 170 hunting dogs and 34 hunters from southern and central-western Brazil, from the Atlantic Forest and Cerrado biomes, respectively, between 2016 and 2018. Serum samples were tested by indirect immunofluorescent-antibody assay (IFA) to detect IgG antibodies against Rickettsia rickettsii , Rickettsia parkeri , Rickettsia bellii , Rickettsia rhipicephali and Rickettsia amblyommatis . Tick species were identified by morphological taxonomic keys, as previously described. A total of 164 ticks including A . sculptum , A . brasiliense and A . aureolatum were tested in PCR assays for Spotted Fever Group (SFG) Rickettsia spp. Results A total of 58/80 (72.5%) wild boars, 24/170 (14.1%) hunting dogs and 5/34 (14.7%) hunters were positive (titers ≥ 64) to at least one Rickettsia species. A total of 669/1,584 (42.2%) ticks from wild boars were identified as Amblyomma sculptum , 910/1,584 (57.4%) as Amblyomma brasiliense , 4/1,584(0.24%) larvae of Amblyomma spp. and 1/1,584 (0.06%) nymph as Amblyolmma dubitatum . All 9 ticks found on hunting dogs were identified as Amblyomma aureolatum and all 22 ticks on hunters as A . sculptum . No tested tick was positive by standard PCR to SFG Rickettsia spp. Conclusions The present study was the concomitant report of wild boar, hunting dog and hunter exposure to SFG rickettsiae agents, performed in two different Brazilian biomes. Wild boar hunting may increase the risk of human exposure and consequently tick-borne disease Wild boars may be carrying and spreading capybara ticks from their original habitats to other ecosystems. Further studies can be required to explore the ability of wild boars to infecting ticks and be part of transmission cycle of Rickettsia spp.

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Introduction: Cart horses are a re-emerging population employed to carry recyclable material in cities. Methods: Sixty-two horses were sampled in an endemic area of human leptospirosis. The microscopic agglutination test (MAT) and real-time polymerase chain reaction (qPCR) were performed. Results: A seropositivity of 75.8% with serovar Icterohaemorrhagiae in 80.8% of the horses was observed. Blood and urine were qPCR negative. MAT showed positive correlations with rainfall (p = 0.02) and flooding (p = 0.03). Conclusions: Although horses may be constantly exposed to Leptospira spp. in the environment mostly because of rainfall and flooding, no leptospiremia or leptospiruria were observed in this study.

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The main pathogenic treponemes causing bovine digital dermatitis were identified from 17 infected herds in southern Brazil for the first time in this study using PCR. We did not find a relationship between treponeme phylogroup composition and clinical classification. Treponema phagedenis was present in all lesions. Rumen fluid was implicated as a reservoir location for these pathogens.A lthough bovine digital dermatitis (BDD) has been known to occur in Brazil since the early 1990s (1), there have been no attempts to describe the possible pathogens involved, apart from reports of histopathological (2) and electron microscopic (3) findings. Treponema species are difficult to culture, so molecular approaches are useful for detecting and identifying these spirochetes (4, 5). The present study describes, for the first time, the frequencies of the major treponeme species in BDD lesions in Brazil. Similar results in Europe, North America, and Asia (6-11) confirm the polytreponemal aspect of this clinical condition.Farms in southern Brazil where BDD infections are endemic (n ϭ 28) were identified by consulting veterinary records. Previously identified dairy cows (n ϭ 200) were individually reexamined and, if positive for BDD (n ϭ 22), were photographed and their lesions classified according to clinical stage, from M1 to M4 (12-14). Samples (n ϭ 22) were surgically excised, placed in phosphatebuffered saline (PBS) solution, and refrigerated (4°C to 8°C) until processing. The infected digit was then topically treated with antibiotics (oxytetracycline) and bandaged. Using a stomach tube, ruminal fluid (Ն50 ml of fresh fluid) was collected from 15 cows from seven different BDD-positive herds, which were chosen by convenience. From one BDD-free herd with a history of lameness but without any clinical BDD lesions detected on previous examinations of the whole herd, ruminal fluid from 10 cows was sampled for use as a negative control. All samples underwent extraction of bacterial DNA, as previously described (12,15). A nested-PCR method was used, as previously described (10). The treponeme-specific primers were called Treponema sp., Treponema medium/T. vincentii-like, Treponema phagedenis-like, and Treponema denticola/T. putidum-like (10). The research was approved by the Committee for the Ethical Use of Animals of Pontifícia Universidade Católica do Paraná (PUCPR) (registration no. 646) in 2011.Of the herds, 17 (60.71%) had BDD lesions on the day of examination and were positive for subsequent molecular BDD detection. The lesions were in different clinical stages (14) and were classified as follows: 13.64% were M1, 45.45% were M2, 22.73% were M3, and 18.18% were M4. However, certain lesions classified as M2 or M3 contained areas that were M4 or M1. In comparison, the cows in the present study exhibited considerably more M2 lesions (45.45% versus 21.03% in the previous study) and fewer M4 lesions (18.18% versus 50.03% in the previous study) ( Table 1). The reason for this observation or why the different forms can transition f...