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The genus Rickettsiacomprises obligatory intracellular bacteria, well known to cause zoonotic diseases around the world. The present work aimed to investigate the occurrence of Rickettsiaspp. in wild animals, domestic dogs and their respective ectoparasites in southern Pantanal region, central-western Brazil, by molecular and serological techniques. Between August 2013 and March 2015, serum, whole blood and/or spleen samples were collected from 31 coatis, 78 crab-eating foxes, seven ocelots, 42 dogs, 110 wild rodents, and 30 marsupials. Serum samples from canids, felids, rodents and marsupials were individually tested by indirect fluorescent antibody test (IFAT) in order to detect IgG antibodies to Rickettsia rickettsii, Rickettsia parkeriand Rickettsia amblyommatis. DNA samples from mammals and ectoparasites were submitted to a multiplex qPCR assay in order to detect and quantify spotted fever group (SFG) and typhus group (TG) rickettsiae and Orientia tsutsugamushi. Positive samples in qPCR assays were submitted to conventional PCR assays targeting gltA, ompA, ompBand htrAgenes, followed by sequencing and phylogenetic analyses. The ticks collected (1582) from animals belonged to the species Amblyomma sculptum, Amblyomma parvum, Amblyomma ovale, Amblyomma tigrinum, Rhipicephalus (Boophilus) microplus, Rhipicephalus sanguineussensu lato and Amblyomma auricularium. Overall, 27 (64.2%) dogs, 59 (75.6%) crab-eating foxes and six (85.7%) ocelots were seroreactive (titer≥64) to at least one Rickettsiaspecies. For 17 (40.4%) dogs, 33 (42.3%) crab-eating foxes, and two (33.3%) ocelots, homologous reactions to R. amblyommatisor a closely related organism were suggested. One hundred and sixteen (23.5%) tick samples and one (1.2%) crab-eating fox blood sample showed positivity in qPCR assays for SFG Rickettsiaspp. Among SFG Rickettsia-positive ticks samples, 93 (80.2%) belonged to A. parvum, 14 (12%) belonged to A. sculptumspecies, three (2.5%) belonged to A. auricularim, and six (5.2%) were Amblyommalarval pools. Thirty samples out of 117 qPCR positive samples for SFG Rickettsiaspp. also showed positivity in cPCR assays based on gltA, htrAand/or ompBgenes. The Blast analyses showed 100% identity with ‘CandidatusRickettsia andeanae’ in all 30 sequences obtained from gltA, htrAand/or ompBgenes. The concatenated phylogenetic analysis based on gltAand 17-kDa htrAgenes grouped the Rickettsiasequences obtained from tick samples in the same clade of ‘CandidatusRickettsia andeanae’. The present study revealed that wild and domestic animals in southern Pantanal region, Brazil, are exposed to SFG rickettsiae agents. Future studies regarding the pathogenicity of these agents are necessary in order to prevent human cases of rickettsiosis in Brazilian southern Pantanal.

New genotypes of Anaplasmataceae agents have been detected in wild carnivores, birds and deer in Brazil. The present work aimed to investigate the presence of Ehrlichiaand Anaplasmaspecies in rodents sampled in Brazil. Additionally, a newly designed quantitative 5′ nuclease real-time multiplex PCR for Ehrlichiaand Anaplasmaspp. detection based on groELgene amplification was designed, showing high specificity and sensitivity (10 groELfragment copy/μL). Between 2000 and 2011, different rodent species [n=60] were trapped in 5 Brazilian biomes. Among 458 rodent spleen samples, 0.4% (2/458) and 2.4% (11/458) were positive for Ehrlichiaand Anaplasmaspp., respectively. Of 458 samples, 2.0% (9/458) and 1.1% (5/458) were positive for Anaplasmasp. and Ehrlichiasp., respectively, using conventional 16S rRNA PCR assays. Maximum Likelihood phylogenetic analyse based on a small region of 16S rRNA genes positioned the Anaplasmagenotypes in rodents near Anaplasma phagocytophilumor Anaplasma marginaleand Anaplasma odocoileiisolates. Ehrlichiagenotypes were closely related to E. canis. There was a low occurrence of Anaplasmaand Ehrlichiain wild and synanthropic rodents in Brazil, suggesting the circulation of new genotypes of these agents in rodents in the studied areas.