The genus Bartonella (Rhizobiales: Bartonellaceae) encompasses facultative intracellular Gram-negative alphaproteobacteria that parasitize mainly erythrocytes and endothelial cells, as well as macrophages, monocytes and dendritic cells. Although they can infect numerous mammal species and arthropod vectors worldwide, reports of Bartonella infections in marsupials are scarce. In fact, such agents have only been detected in marsupials and/or associated ectoparasites in Australia and the United States of America until the present moment. The present study aimed to isolate and characterize molecularly, morphologically and phenotypically Bartonella infecting free-living marsupials sampled in the Brazilian Pantanal, the largest wetland in South America. Two marsupials were captured in December 2018 and six marsupials in February 2019, totaling eight small mammals sampled: five (62.5%) Thylamys macrurus and three (37.5%) Monodelphis domestica. All blood samples were submitted to qPCR for Bartonella spp. based on the nuoG gene, a pre-enrichment liquid culture and a chocolate agar solid culture. Bartonella sp. was isolated from 3 T. macrurus and one M. domestica. One Bartonella isolate obtained from a T. macrurus blood sample (strain 117A) that showed to be closely related to the Bartonella vinsonii complex and Bartonella machadoae was selected for whole genome sequencing using a hybrid approach based on Illumina NovaSeq and Nanopore sequencing platforms. This strain showed a genome of 2.35 Mbp, with an average C + G content of 38.8%, coding for 2013 genes, and a 29 kb plasmid with an average C + G content of 34.5%. In addition, this strain exhibited an average nucleotide identity (ANI) of 85% with Bartonella species belonging to the B. vinsonii group and 91% with B. machadoae. Phylogenomic analysis based on 291 protein coding genes shared by the genomes of 53 Bartonella species positioned this strain closely to B. machadoae. This new isolated species was named Bartonella harrusi sp. nov., which was characterized as having small capnophilic, microaerophilic and aerobic rods with an absence of pili and flagella. In conclusion, the present work describes the biochemical, phenotypic and genomic characteristics of Bartonella harrusi, a new species isolated from the T. macrurus blood samples of the Brazilian Pantanal. Finally, a review of the taxonomic classification of members of the genus Bartonella is proposed, based on the ANI values accessed by whole genome sequencing analyses.

Even though the epidemiology of tick-borne agents (TBA) in dogs has been extensively investigated around the world, the occurrence, vectors involved, and molecular identity of these agents in cats remains elusive in many regions. Among TBA, Ehrlichia, Anaplasma, Babesia, Cytauxzoon, and Hepatozoon are responsible for diseases with non-specific clinical signs in cats, making essential the use of molecular techniques for accurate diagnosis and proper treatment. The present work aimed to investigate the occurrence and molecular identity of tick-borne agents (Ehrlichia, Anaplasma, Babesia/Theileria, Cytauxzoon, and Hepatozoon) in cats from southeastern (states of São Paulo (SP) and Minas Gerais (MG)) and northern (state of Rondônia (RO)) Brazil. For this purpose, 390 blood samples were collected from domiciled cats in MG (n = 155), SP (n = 151), and RO(n = 84) states, submitted to DNA extraction and PCR assays for Ehrlichia spp. (dsb gene), Anaplasma spp. (rrs gene), piroplasmids (18S rRNA gene), and Hepatozoon spp. (18S rRNA gene), sequencing, and phylogenetic inferences. The overall positivity for Anaplasma spp., Ehrlichia spp., Babesia/Theileria spp., Cytauxzoon spp., and Hepatozoon spp. were 7.4% (12.3% (MG) and 6.6% (SP)), 2% (4.5% (MG) and 0.6% (SP)), 0.7% (0.6% (MG), 0.6% (SP) and 1.2% (RO)), 27.2% (41.9% (MG), 24.5% (SP) and 4.8% (RO), and 0%, respectively. The phylogenetic analysis grouped the obtained sequences with ‘Candidatus Anaplasma amazonensis’, A. platys, B. vogeli, and Cytauxzoon sp. previously detected in wild felids from Brazil. qPCR specific for E. canis based on the dsb gene confirmed the molecular identity of the detected ehrlichial agent. The present study expanded the list and geographical distribution of hemoparasites in cats. ‘Candidatus Anaplasma amazonensis’, recently detected in sloths from northern Brazil, was described for the first time in cats. This is the first report of piroplasmids infecting cats in northern Brazil. Coinfection by Cytauxzoon and other TBA (Ehrlichia, Anaplasma, and B. vogeli) reported in the present study raises the need for veterinary practitioners’ awareness of cats parasitized by multiple TBA.

Bovine leptospirosis assumes great economic importance since it affects several production aspects. Therefore, knowledge about the occurrence and distribution of this disease is fundamental to adopt the correct prevention measures. The present study aimed to evaluate the frequency of anti-Leptospira spp. antibodies in 24,483 bovine serum samples received between 2007 to 2015 from 21 Brazilian states. Of these, 8,643 (35.3%) were reagents in the microscopic agglutination test to one or more serovars of Leptospira spp. The most frequent serovars were Wolffi (61.47%), Tarassovi (9.62%) and Pomona (7.20%). Hardjo serovar presented a prevalence of 6.27%. Among the 21 states analyzed, the State of Pernambuco had the highest frequency with 88.24% and the State of São Paulo was the origin of the largest number of analyzed samples (13,838), with a frequency of 31.54% of reagents. The results demonstrate a high exposure to several serovars of Leptospira spp. in bovine species in Brazilian states, showing the importance of adopting prophylactic measures in order to reduce the risk of infection in this specie.

Resumo A leptospirose é uma zoonose de distribuição mundial causada por bactérias do gênero Leptospira spp. Nos equídeos, a não eliminação deste microrganismo dos túbulos renais após a resolução da bacteremia torna tal espécie uma importante fonte de infecção na cadeia epidemiológica da doença. Desta forma, este estudo avaliou a frequência de aglutininas anti-Leptospira em amostras de soro de equídeos abatidos em frigorífico exportador. Foram coletadas 107 amostras de soro equídeo durante o abate. Dessas, 73 eram provenientes de equídeos machos e 34 de fêmeas. Esses animais, sem raça definida, eram provenientes dos estados de Minas Gerais, São Paulo, Goiás, Bahia e Mato Grosso do Sul. A Soroaglutinação Microscópica (SAM) foi empregada como método diagnóstico e foram utilizadas 24 sorovariedades de Leptospira spp. Uma proporção de 92,52% dos animais foi reagente a uma ou mais sorovariedades na SAM, com títulos iguais ou superiores a 100. As sorovariedades de maior ocorrência foram Icterohemorrhagiae (71,96%), Cynopteri (38,22%), Grippotyphosa (29,91%) e Pyrogenes (26,17%). Observou-se que 100% dos municípios possuíam animais soropositivos a uma ou mais sorovariedades de Leptospira spp. A partir dos resultados obtidos pode-se confirmar a importância dos equídeos na cadeia epidemiológica da leptospirose, uma vez que a eliminação deste microrganismo através da urina ocorre por muitas semanas após a infecção. Tais resultados também demonstram que estes equídeos foram altamente expostos a diversas sorovariedades de Leptospira spp. Desta forma, a leptospirose equina não deve ser negligenciada, a fim de assegurar a saúde pública e a saúde animal, bem como reduzir os riscos ocupacionais. PALAVRAS-CHAVE: LEPTOSPIROSE. EQUINOS. DIAGNÓSTICO SOROLÓGICO. ÁREA TEMÁTICA: Epidemiologia