PDF(Pubmed)
Abstract：
Standard- and large-sized eggs of Trichuris trichiura were found in the feces of schoolchildren in Yangon, Myanmar during epidemiological surveys and mass deworming with albendazole in 2017-2019. The standard-sized eggs were identified as those of T. trichiura, but it was necessary to exclude the possibility of the large-sized eggs belonging to Trichuris vulpis, a dog whipworm. We conducted morphological and molecular studies to determine the species of the 2 types of Trichuris eggs. Individual eggs of both sizes were isolated from Kato-Katz fecal smears (n=20) and mechanically destroyed using a 23G injection needle. Nuclear DNA was extracted, and the 18S rRNA region was sequenced in 15 standard-sized eggs and 15 large-sized eggs. The average size of standard-sized eggs (T. trichiura) was 55.2×26.1 μm (range: 51.7-57.6×21.3-28.0 μm; n=97), whereas the size of large-sized eggs was 69.3×32.0 μm (range: 65.1-76.4×30.1-34.5 μm; n=20), slightly smaller than the known size of T. vulpis. Regarding standard-sized eggs, the 18S rRNA nucleotide sequences exhibited 100% homology with T. trichiura deposited in GenBank and 88.6-90.5% homology with T. vulpis. Regarding large-sized eggs, the nucleotide sequences showed 99.8-100% homology with T. trichiura in GenBank and 89.6-90.7% homology with T. vulpis. Both standard- and large-sized eggs of Trichuris spp. found in Myanmar schoolchildren during 2017-2019 were morphologically and molecularly confirmed to belong to T. trichiura. The conversion of eggs from smaller to large sizes might be due to anthelmintic treatments with albendazole.
摘要：
仰光学童的粪便中发现了标准和大尺寸的Trichuristrichiura卵，2017-2019年缅甸流行病学调查和阿苯达唑大规模驱虫。标准大小的卵被鉴定为T.trichiura的卵，但是有必要排除属于毛虫的大型卵的可能性，一只狗鞭虫。我们进行了形态学和分子研究，以确定两种类型的毛虫卵的种类。从Kato-Katz粪便涂片（n=20）中分离出两种大小的单个卵，并使用23G注射针进行机械破坏。提取了核DNA,并在15个标准大小的卵和15个大大小的卵中对18SrRNA区域进行测序。标准大小鸡蛋的平均大小(T.trichiura）为55.2×26.1μm（范围：51.7-57.6×21.3-28.0μm；n=97），而大型卵的大小为69.3×32.0μm（范围：65.1-76.4×30.1-34.5μm；n=20），略小于已知的T.vulpis大小。关于标准大小的鸡蛋，18SrRNA核苷酸序列与存放在GenBank中的T.trichiura具有100％的同源性，与T.vulpis具有88.6-90.5％的同源性。关于大型鸡蛋，核苷酸序列与GenBank中的T.trichiura具有99.8-100％的同源性，与T.vulpis具有89.6-90.7％的同源性。Trichurisspp的标准和大型卵。在2017-2019年期间在缅甸发现的学童在形态和分子上被证实属于T.trichiura。卵从较小尺寸转变为较大尺寸可能是由于阿苯达唑的驱虫治疗。
