Kulthida Kopolrat1, Paiboon Sithithaworn2, Nadda Kiatsopit1, Opal Pitaksakulrat3, Smarn Tesana4, Ross H Andrews5, Trevor N Petney6. 1. Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. 2. Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand Cholangiocarcinoma Screening and Care Program (CASCAP), Khon Kaen University, Khon Kaen 4000, Thailand paibsit@gmail.com paib_sit@kku.ac.th. 3. Faculty of Veterinary Science (Establishment Project), Prince of Songkla University, Songkhla 90110, Thailand. 4. Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand. 5. Liver Fluke and Cholangiocarcinoma Research Center, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand Cholangiocarcinoma Screening and Care Program (CASCAP), Khon Kaen University, Khon Kaen 4000, Thailand Imperial College London, Faculty of Medicine, St Mary's Campus, South Wharf Street, London W2 1NY. UK. 6. Cholangiocarcinoma Screening and Care Program (CASCAP), Khon Kaen University, Khon Kaen 4000, Thailand Institute of Zoology 1: Ecology and Parasitology, Karlsruhe Institute of Technology, Kornblumen Strasse 13, Karlsruhe, Germany.
Abstract
BACKGROUND: Previous studies indicate that Opisthorchis viverrini sensu lato (s.l.) is a species complex with strong associations to geographical regions, i.e., specific wetlands. The present study was conducted to compare the infectivity, establishment and metacercarial burden and survival of the fish host following exposure to O. viverrini s.l. cercariae isolates from two different river wetlands. METHODS: Experimental infections were performed by exposing fish (silver barb, Barbonymus gonionotus) individually to 0 (control) and 100 O. viverrini s.l. cercariae originating from the Songkram River wetland in Thailand and the Nam Ngum River wetland, Lao PDR. Metacercarial burden and fish survivals were monitored after infection. RESULTS: Fish exposed to O. viverrini s.l. cercariae from the Nam Ngum River wetland had significantly greater metacercarial burden and more active motility at 28 and 35 days post infection than those from the Songkram River wetland. The mortality of fish infected with O. viverrini s.l. from the Nam Ngum River wetland was greater than that from the Songkram River wetland (log-rank test, p<0.01). CONCLUSIONS: The findings in this study provided additional evidence supporting the importance of cryptic species of O. viverrini s.l. and it has implications for parasite transmission dynamics, life cycle success and disease ecology.
BACKGROUND: Previous studies indicate that Opisthorchis viverrini sensu lato (s.l.) is a species complex with strong associations to geographical regions, i.e., specific wetlands. The present study was conducted to compare the infectivity, establishment and metacercarial burden and survival of the fish host following exposure to O. viverrini s.l. cercariae isolates from two different river wetlands. METHODS: Experimental infections were performed by exposing fish (silver barb, Barbonymus gonionotus) individually to 0 (control) and 100 O. viverrini s.l. cercariae originating from the Songkram River wetland in Thailand and the Nam Ngum River wetland, Lao PDR. Metacercarial burden and fish survivals were monitored after infection. RESULTS: Fish exposed to O. viverrini s.l. cercariae from the Nam Ngum River wetland had significantly greater metacercarial burden and more active motility at 28 and 35 days post infection than those from the Songkram River wetland. The mortality of fish infected with O. viverrini s.l. from the Nam Ngum River wetland was greater than that from the Songkram River wetland (log-rank test, p<0.01). CONCLUSIONS: The findings in this study provided additional evidence supporting the importance of cryptic species of O. viverrini s.l. and it has implications for parasite transmission dynamics, life cycle success and disease ecology.
Authors: Thomas Hughes; Thomas O'Connor; Anchalee Techasen; Nisana Namwat; Watcharin Loilome; Ross H Andrews; Narong Khuntikeo; Puangrat Yongvanit; Paiboon Sithithaworn; Simon D Taylor-Robinson Journal: Int J Gen Med Date: 2017-08-10