title: High susceptibility of Neotricula aperta gamma-strain from Krakor and Sdau in Cambodia to Schistosoma mekongi from Khong Island in Laos.
abstract: Neotricula aperta gamma-strain snails collected from Krakor and Sdau in Cambodia were found to have the same or higher susceptibility to Schistosoma mekongi as N. aperta originally isolated from Khong in Laos. Infection rates of N. aperta gamma-strain snails exposed to 3 miracidia at week 8 were: Khong gamma-strain, 22.6%; Krakor gamma-strain, 33.3%; and Sdau gamma-strain, 67.4%. At week 10, the Sdau gamma-strain showed the highest infection rate of 83.3%. We thus found significantly high susceptibility of the Sdau gamma-strain to S. mekongi originally isolated from Khong. However, in another experiment, susceptibility of the Sdau gamma-strain was rather comparable to that of Khong and Krakor gamma-strain. We also found no significant differences in infection and survival rates between the Khong and Krakor gamma-strain when the snails were exposed to 3 or 6 miracidia. This is the first report to confirm the high susceptibility in the laboratory of N. aperta gamma-strain snails from endemic areas in Cambodia to S. mekongi originally isolated from Laos. The high susceptibility of N. aperta gamma-strain snails to S. mekongi in distant areas may be an important factor in the endemic transmission of human schistosomiasis.
authors.affiliation: Department of Tropical Medicine and Parasitology, Dokkyo Medical University School of Medicine, Mibu, Shimotsuga, Tochigi 321-0293, Japan.
authors.forename: Mizuho
authors.initials: M
authors.lastname: Shimada
authors.forename: Naoko
authors.initials: N
authors.lastname: Kato-Hayashi
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Chigusa
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakamura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ohmae
authors.forename: Muth
authors.initials: M
authors.lastname: Sinuon
authors.forename: Duong
authors.initials: D
authors.lastname: Socheat
authors.forename: Viroj
authors.initials: V
authors.lastname: Kitikoon
authors.forename: Hajime
authors.initials: H
authors.lastname: Matsuda
mesh_terms: D000818:Animals; D002160:Cambodia / Q000453:epidemiology; D006801:Humans; D007812:Laos / Q000453:epidemiology; D012547:Schistosoma / Q000472:pathogenicity*; D012552:Schistosomiasis / Q000453:epidemiology / Q000469:parasitology / Q000635:transmission*; D012908:Snails / Q000145:classification* / Q000469:parasitology*