Instituto Oswaldo Cruz/Fiocruz, Manguinhos, RJ, Brazil.
Acta Trop. 2010 Sep;115(3):194-9. doi: 10.1016/j.actatropica.2010.01.005. Epub 2010 Jan 18.
The human cases of eosinophilic meningitis recently reported from Brazil have focused the attention of the public health agencies on the role the introduced snail Achatina fulica plays as hosts of the metastrongylid nematodes. Determining the potential of this snail to host and develop infective larval stages of metastrongylids in the wild and identify the species harbored by them is crucial for designing effective control measures. Here we assess if A. fulica may act as intermediate host of A. cantonensis at the peridomiciliary areas of a patient's house from state of Pernambuco (PE), who was diagnosed with eosinophilic meningitis and a history of ingesting raw molluscs. Larvae obtained from naturally infected A. fulica were orally administered to Rattus norvegicus. The worms were collected from the pulmonary artery and brain, and were morphologically characterized and compared to the Japan isolate of A. cantonensis. Adult worms and infective L(3) larvae (PE isolate) recovered from A. fulica specimens were also analyzed by polymerase chain reaction and restriction fragment length polymorphism of ITS2 region from rDNA and compared to A. cantonensis (ES isolate), A. vasorum (MG isolate) and A. costaricensis (RS isolate). The large size of the spicules (greater than those observed in other species of Angiostrongylus) and the pattern of the bursal rays agree with the original species description by Chen (1935). Furthermore, the morphology of the PE isolate was similar to that of Japan isolate. The PCR-RFLP profiles obtained were distinctive among species and no variation in patterns was detected among adult individuals from A. cantonensis isolates from PE and ES. The importance of A. fulica as an intermediate host of eosinophilic menigoencepahlitis in Brazil is emphasized.
最近在巴西报道的人类嗜酸性脑膜炎病例引起了公共卫生机构对引入的蜗牛 Achatina fulica 在作为中间宿主来携带并发育旋尾线虫的有感染力的幼虫阶段的作用的关注。确定这种蜗牛在野外作为中间宿主来携带并发育旋尾线虫的幼虫阶段，并鉴定它们所携带的物种，对于设计有效的控制措施至关重要。在这里，我们评估 A. fulica 是否可以作为 Pernambuco 州（PE）一位被诊断患有嗜酸性脑膜炎且有生食贝类史的患者住所周围的中间宿主来携带 A. cantonensis。从自然感染的 A. fulica 中获得的幼虫被口服给予 Rattus norvegicus。从肺动脉和大脑中收集蠕虫，并进行形态学特征描述，并与日本的 A. cantonensis 分离株进行比较。从 A. fulica 标本中回收的成虫和感染性 L(3)幼虫（PE 分离株）也通过聚合酶链反应和 rDNA 的 ITS2 区域的限制性片段长度多态性进行分析，并与 A. cantonensis（ES 分离株）、A. vasorum（MG 分离株）和 A. costaricensis（RS 分离株）进行比较。棘的大小较大（大于其他 Angiostrongylus 物种观察到的大小）和小钩射线模式与 Chen（1935 年）的原始物种描述一致。此外，PE 分离株的形态与日本分离株相似。获得的 PCR-RFLP 图谱在种间具有独特性，并且在来自 PE 和 ES 的 A. cantonensis 分离株的成虫个体中未检测到图谱变化。强调了 A. fulica 在巴西作为嗜酸性脑膜炎的中间宿主的重要性。
