Sánchez-Montes Sokani, Guzmán-Cornejo Carmen, Martínez-Nájera Yecenia, Becker Ingeborg, Venzal José M, Labruna Marcelo B
Laboratorio de Acarología, Departamento de Biología Comparada, Facultad de Ciencias, Universidad Nacional Autónoma de México, Distrito Federal, México; Laboratorio de Inmunoparasitología, Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Distrito Federal, México; Centro de Medicina Tropical, Unidad de Investigación en Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, Distrito Federal, México.
Laboratorio de Acarología, Departamento de Biología Comparada, Facultad de Ciencias, Universidad Nacional Autónoma de México, Distrito Federal, México.
Ticks Tick Borne Dis. 2016 Oct;7(6):1097-1101. doi: 10.1016/j.ttbdis.2016.09.003. Epub 2016 Sep 11.
The genus Rickettsia includes obligate intracellular bacteria transmitted by several hematophagous arthropods such as ticks, fleas and sucking lice. In particular hard ticks (Ixodidae) have been cited as the main vectors of pathogenic rickettsiae in Mexico. However, there have been only two records of a single Rickettsia species associated with Mexican soft ticks (Argasidae). In this study, we searched for rickettsial DNA in argasid ticks (13 adults and eight nymphs of Ornithodoros yumatensis) from two bat caves in the state of Yucatan, Mexico. Additionally one larva collected in a cave from Chiapas, Mexico, and associated with Desmodus rotundus was used to corroborate the tick taxonomic determination. Of these, nine ticks (43%) yielded expected PCR products for the rickettsial gltA gene. These PCR-positive ticks were tested with additional PCR protocols targeting the rickettsial genes gltA, ompA and ompB. DNA partial sequences from these genes showed 99-100% identities with Rickettsia lusitaniae, an agent isolated from O. erraticus in Portugal, and closely related to R. felis and R. hoogstraalii. Based on the results from this study, the inventory of rickettsiae distributed in Mexico increases from six to seven species.
立克次氏体属包括专性细胞内细菌，由几种吸血节肢动物传播，如蜱、跳蚤和吸血虱。特别是硬蜱（硬蜱科）被认为是墨西哥致病性立克次氏体的主要传播媒介。然而，仅有两份关于与墨西哥软蜱（argasidae）相关的单一立克次氏体物种的记录。在本研究中，我们在墨西哥尤卡坦州两个蝙蝠洞穴中的argasid蜱（13只尤马钝缘蜱成虫和8只若虫）中搜索立克次氏体DNA。此外，在墨西哥恰帕斯州一个洞穴中采集的、与圆叶吸血蝠相关的一只幼虫被用于证实蜱的分类鉴定。其中，9只蜱（43%）产生了立克次氏体gltA基因的预期PCR产物。这些PCR阳性蜱用针对立克次氏体基因gltA、ompA和ompB的额外PCR方案进行了检测。这些基因的DNA部分序列与葡萄牙从奇异钝缘蜱中分离出的立克次氏体卢西塔尼亚种显示出99 - 100%的同一性，并且与猫立克次氏体和胡氏立克次氏体密切相关。基于本研究结果，墨西哥分布的立克次氏体种类从6种增加到了7种。
