||Bondad-Reantaso Melba, Berthe Franck
||Building Capacity to Combat impacts of Aquatic Alein Invasive species and associated trans-boundary pathogens in ASEAN
||Présentation Workshop on Building Capacity to Combat impacts of Aquatic Alien Invasive Species and Associated Trans-boundary Pathogens in ASEAN, 13-16 July 2004, Penang, Malaysia
||Pathogens, Diseases, Impact, Introductions, Transfers, Molluscan Pathogens
||Pacific oysters were introduced into west coast of the USA from Matsushima Bay in Japan, infected with low levels of Haplosporidiumsp. identical to H.nelsoni(MSX) which causes high mortalities of Eastern oyster (C. virginica). A highly specific and sensitive DNA probe for H. nelsonican also detect Haplosporidium sp. in C.gigas of western US and Japan (Burreson and Stokes 2000).In 2002, H. nelsoni was detected in Japan using the same probe (Kamaishi and Yoshinaga 2002).Lesson: it appears that H. nelsoni does not cause serious disease in Pacific oysters; H. nelsoniis now speculated to have been introduced into the Pacific US by apparently healthy but infected C. gigas. Infected C. gigaswere introduced onto the east coast of the US where the parasite shifted its virulence into a new host, infecting Eastern oystersand causing mass mortalities. H.nelsoni has also been reported from Korea in 1971 at that under the name of Minchinia sp. (Kern 1976). H. nelsoni has been reported from Pacific oyster in France (Renault et al. 2000) and may have been introduced with P. oyster imports to replace Ostrea edulis devastated by Marteilia refringens and Bonamia ostrea. Canada reported for the first time H. nelsoni infection in 2002.