Paragonimiasis and its intermediate hosts in a transmission focus in Lao People's Democratic Republic

• Published in: Acta tropica Vol. 103; no. 2; pp. 108 - 115
• Main Authors: Odermatt, P., Habe, S., Manichanh, S., Tran, D.S., Duong, V., Zhang, Wei, Phommathet, K., Nakamura, S., Barennes, H., Strobel, M., Dreyfuss, G.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-08-2007; Elsevier
• Subjects: Adolescent; Adult; Animals; Biological and medical sciences; Child; Chulathelphusa brandti; Crab; Decapoda; Decapoda (Crustacea) - parasitology; Diseases caused by trematodes; Distomatoses; Dogs; Epidemiology; Female; Freshwater; General aspects; Helminthic diseases; Humans; Infectious diseases; Intermediate host; Laos; Laos - epidemiology; Life Cycle Stages; Macrobrachium; Male; Medical sciences; Mycobacterium; P. harinasutai; P. heterotremus; P. westermani; Paragonimiasis; Paragonimiasis - epidemiology; Paragonimiasis - parasitology; Paragonimiasis - transmission; Paragonimus; Paragonimus - classification; Paragonimus - growth & development; Paragonimus bangkokensis; Parasitic diseases; Potamon; Potamon lipkei; Prawn; Snail; Snails - parasitology; Zoonoses - parasitology; Zoonoses - transmission; Asia; Laos; P. westermani; P. harinasutai; Prawn; P. heterotremus; Snail; Epidemiology; Paragonimus bangkokensis; Chulathelphusa brandti; Paragonimiasis; Crab; Intermediate host; Potamon lipkei; Laos; Distomatosis; Trematode disease; Transmission; Gastropoda; Parasitosis; Helminthiasis; Infection; Tropical medicine; Invertebrata; Mollusca; Public health
• ISSN: 0001-706X; 1873-6254
• DOI: 10.1016/j.actatropica.2007.05.015

Human cases of paragonimiasis have been reported in Lao People's Democratic Republic from several provinces, however, detailed descriptions of a focus of transmission including parasites species and intermediate hosts are lacking. Field investigations were carried out between February and July 2004 in three neighboring villages of the province of Vientiane. Persons with chronic cough (more than three weeks) were identified during a door-to-door survey and three sputum samples were examined for Paragonimus spp. and tuberculosis on two consecutive days. Potential intermediate snail and crustacean hosts were sampled among the populations’ water-contact sites and examined for metacercarial infections or cercarial shedding. Four dogs were infected with metacercaria and the species of the subsequently retrieved adult parasites were identified. 12.7% (15 cases) of all chronic cough patients (0.6% of the total population) suffered from paragonimiasis. Samples of five species of freshwater snails, two species of crabs and one species of prawn were collected from the Nam Sêt River. None of the snails were infected. Metacercariae of P. harinasutai, P. bangkokensis and P. heterotremus were found in Potamon lipkei crabs while an infection with P. westermani was observed in a Chulathelphusa brandti crab. No paragonimid metacercaria was found in the Macrobrachium dienbienphuense prawns Dang and Nguyen 1972. This study demonstrates the importance of Paragonimus spp. as an etiological agent in patients with chronic cough and suggests that similar transmission might be widespread in Lao People's Democratic Republic. We document herein the transmission of several Paragonimus species indicating that paragonimiasis is an active zoonosis in Lao People's Democratic Republic.