title: Effects of albendazole, artesunate, praziquantel and miltefosine, on Opisthorchis viverrini cercariae and mature metacercariae.
abstract: OBJECTIVE
  To explore larvicidal effects of anthelmintic drugs on Opisthorchis viverrini (O. viverrini) for alternative approach to interrupting its cycle for developing a field-based control program.
  
  
  METHODS
  The larvicidal activities of albendazole (Al), artesunate (Ar), praziquantel (Pzq) and miltefosine (Mf) on O. viverrini cercariae and mature metacercariae were investigated. Lethal concentrations (LC50and LC95) of these drugs were determined. Mature metacercariae previously exposed to various concentrations of the drugs were administered to hamsters. Worms were harvested 30 d post infection and worm recovery rates calculated. Al, Ar, Pzq and Mf produced morphological degeneration and induced shedding tails of cercariae after 24 h exposure.
  
  
  RESULTS
  The LC50and LC95of Al, Ar, Pzq and Mf on cercariae were 0.720 and 1.139, 0.350 and 0.861, 0.017 and 0.693, and 0.530 and 1.134 ppm, respectively. LC50and LC95of Ar on mature metacercariae were 303.643 and 446.237 ppm and of Mf were 289.711 and 631.781 ppm, respectively but no lethal effect in Pzq- and Al-treated groups (up to 1 ppt). No worms were found in hamsters administered Pzq-treated metacercariae. The adult worms from Al-treated metacercariae were significantly bigger in size compared to the control group (P < 0.05). Fecundity and body width were greater in adults from Mf-treated metacercariae compared to the control group (P < 0.05).
  
  
  CONCLUSIONS
  The larvicidal effects of these drugs were high efficacy to O. viverrini cercariae but lesser efficacy to metacercariae. It should be further studied with the eventual aim of developing a field-based control program.
authors.affiliation: Food-Borne Parasite Research Group, Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Phornphitcha
authors.initials: P
authors.lastname: Pechdee
authors.affiliation: Food-Borne Parasite Research Group, Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Monticha
authors.initials: M
authors.lastname: Chaiyasaeng
authors.affiliation: Food-Borne Parasite Research Group, Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Chanisala
authors.initials: C
authors.lastname: Sereewong
authors.affiliation: Food-Borne Parasite Research Group, Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Jukkrid
authors.initials: J
authors.lastname: Chaiyos
authors.affiliation: Food-Borne Parasite Research Group, Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Apiporn
authors.initials: A
authors.lastname: Suwannatrai
authors.affiliation: Department of Fisheries, Faculty of Agriculture, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Sutee
authors.initials: S
authors.lastname: Wongmaneeprateep
authors.affiliation: Food-Borne Parasite Research Group, Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand. Electronic address: smarn_te@kku.ac.th.
authors.forename: Smarn
authors.initials: S
authors.lastname: Tesana
keywords: Albendazole; Artesunate; Cercariae; Miltefosine; Opisthorchis viverrini; Praziquantel