Study of diagnosis and spatial epidemiology on paragonimiasis in Lao PDR.

尽管自1973年以来老挝缺乏关于肺吸虫病的信息，但通过我们的研究，明确了5个省的8个地区; Attopeu，Champasak，Savannakhet，Vientiane和Luangnamtha存在和/或可能存在该病的风险。从Hinheup区获得的2种河蟹（7种Lipkei溪蟹和5种Chulathelphusa brandti）中采集了约700个囊蚴，Hinheup区是万象省的一个密集出没区，距离老挝首都万象以北80 km。虽然数量较少，但在后尾蚴种群中鉴定出异盘并殖吸虫（一种已知的引起中南半岛地区人类副殖吸虫病的种）和卫氏并殖吸虫。在主要种群中，使用实验室犬实验感染获得的蠕虫并澄清了2种未报告的并殖吸虫属种harinastai和bankokensis。在各种实验动物中，哈氏疟原虫蠕虫在大鼠实验感染3个月后不能存活，这是首次证实。此外，狗是班戈疟原虫的合适宿主，在实验感染中蠕虫的回收率（80%）证实了这一点。采用已建立的PCR技术。为确定Hinheup地区人并殖吸虫病的病原种类，从居民粪便中采集了6份并殖吸虫卵，采用4种并殖吸虫种特异性区（ITS 2）引物，建立了PCR技术。所有这些样本均为异盘并殖吸虫，因此强烈建议该地区的人并殖吸虫病原体为该种。

In spite of lack of information on paragonimiasis in Laos since 1973, eight districts in 5 provinces; Attopeu, Champasak, Savannakhet, Vientiane, and Luangnamtha, which exist and/or possible risk of the disease were clarified through our research. Around 700 metacercariae were collected from 2 species of the river crabs (7 Potamon lipkei and 5 Chulathelphusa brandti) obtained in Hinheup district which was especially investigated as a dense infested area in Vientiane province, where is 80 km north from Vientiane Capital in Lao PDR. Though the numbers were smaller, Paragonimus heterotremus, a known causative species of human parogonimiasis in Indochina region, and P. westermani were identified at the metacercariae population. On the major population, 2 unreported Paragonimus species of harinastai and bankokensis were identified and clarified using adult worms obtained from experimental infections of dogs in the laboratory. Among various experimental animals, adult worms of P. harinastai never survive after 3 month of the experimental infections in rats, which was demonstrated for the first time. Furthermore, dog is a suitable host for P. bankokensis was confirmed by recovery (80%) of the adult worms at the experimental infections. And the established PCR technology was used. To identify the actual causative species of human paragonimiasis in Hinheup, 6 samples of the parasite eggs from the sputa of dwellers were collected, and the established PCR technique; using primers of species specific region (ITS2) of the 4 parasites, was performed. All these samples resulted in P. heterotremus, thus the causative parasite of human paragonimiasis was strongly suggested as this species in the region.