Universidade Estadual do Maranhão (UEMA), São Luis, MA, Brazil.
Vector-Borne Bioagents Laboratory (VBBL), Department of Pathology, Reproduction and One Health, School of Agricultural and Veterinarian Sciences (FCAV), São Paulo State University (Unesp), Jaboticabal, SP, Brazil.
Acta Trop. 2023 Aug;244:106955. doi: 10.1016/j.actatropica.2023.106955. Epub 2023 May 25.
Opossums are synanthropic marsupials able to interchange among wild, peri‑urban and urban environments, playing an epidemiologically important role as hosts for emerging pathogens and ectoparasites of relevance in public health. The present study aimed to detect and molecularly characterize vector-borne agents in a population of common opossums (Didelphis marsupialis) from the Island of São Luís do Maranhão, northeastern Brazil. Of the 45 animals analyzed, one (2.22%) was positive in the nested PCR assay based on the 18S rRNA gene of piroplasmids. The obtained sequence was phylogenetically positioned in a clade containing sequences of Babesia sp. previously detected in Didelphis aurita, Didelphis albiventris and associated ticks from Brazil. Eight (17.77%) samples were positive in PCR for Ehrlichia spp. based on the dsb gene; four samples were sequenced and positioned into a new clade, sister to E. minasensis and Ehrlichia sp. clade detected in Superorder Xenarthra mammals. No samples tested positive in the screening PCR assays based on the 16S rRNA gene of Anaplasma spp. Two samples were positive in the qPCR for Bartonella spp. based on the nuoG gene. Seven animals (15.56%) were positive in the nPCR based on the 16S rRNA gene of hemoplasmas. Of these, three were positive in a PCR based on the 23S rRNA gene. The phylogenies based on both 16S rRNA and 23S rRNA genes corroborated to each other and positioned the sequences in the same clade of hemoplasmas previously detected in D. aurita and D. albiventris sampled in Brazil. Finally, three (6.66%) animals were positive in the PCR for Hepatozoon spp.; the obtained 18S rRNA sequence was positioned into the H. felis clade.The present study showed, for the first time, the circulation of piroplasmids, Hepatozoon spp., Ehrlichia spp., hemoplasmas and Bartonella spp. in D. marsupialis sampled in northeastern Brazil, with description of putative novel genotypes of Ehrlichia and Hepatozoon and copositivity by different vector-borne agents. The present work consolidates the "South American Marsupialia" piroplasmid clade, adding one more genotype of Babesia sp. to this clade.
负鼠是能够在野生、城郊和城市环境之间转换的共生有袋动物，作为新兴病原体和与公共卫生相关的外寄生虫的宿主，在流行病学上起着重要作用。本研究旨在检测和分子特征巴西马瑙斯岛常见负鼠（Didelphis marsupialis）种群中的媒介传播病原体。在基于 18S rRNA 基因的焦虫嵌套 PCR 检测中，45 只动物中有 1 只（2.22%）呈阳性。获得的序列在一个包含先前在巴西的 Didelphis aurita、Didelphis albiventris 和相关蜱中检测到的贝氏疟原虫序列的分支中进行了系统发育定位。8 份（17.77%）基于 dsb 基因的 Ehrlichia spp. PCR 检测呈阳性；4 个样本进行了测序，并被定位到一个新的分支，与 Superorder Xenarthra 哺乳动物中的 E. minasensis 和 Ehrlichia sp. 分支相姐妹。在基于 16S rRNA 基因的 Anaplasma spp. 的筛查 PCR 检测中，没有样本呈阳性。基于 nuoG 基因的 Bartonella spp. qPCR 检测有 2 个样本呈阳性。7 个动物（15.56%）基于 16S rRNA 基因的 nPCR 对血支原体呈阳性。其中 3 个在基于 23S rRNA 基因的 PCR 中呈阳性。基于 16S rRNA 和 23S rRNA 基因的系统发育彼此一致，并将序列定位在先前在巴西采样的 D. aurita 和 D. albiventris 中检测到的血支原体的同一分支中。最后，3 只（6.66%）动物对 Hepatozoon spp. PCR 呈阳性；获得的 18S rRNA 序列被定位到 H. felis 分支中。本研究首次显示，在巴西东北部采样的负鼠中循环存在焦虫、Hepatozoon spp.、Ehrlichia spp.、血支原体和 Bartonella spp.，并描述了 Ehrlichia 和 Hepatozoon 的可能新基因型和不同媒介传播病原体的共同阳性。本工作巩固了“南美洲有袋类动物”疟原虫分支，为该分支增加了一个新的贝氏疟原虫基因型。
