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疾病描述：
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1.病原概述
病原型別：病毒(virus)
病原環境： 海水、淡水、半淡鹹水 (Brackish Water, Marine 、freshwater)
學名：
病名(及俗名)：acute catarrhal enteritis
最早發現者：Wolf, snieszko et al 1960
ＯＩＥ狀況：表列(Listed)
病原摘要：病毒顆粒為二十面體，其大小約60nm(fig1)，具有兩段雙股RNA (bi-segmented double –stranded RNA)，由分離之病毒之中和試驗 (neutralization tests)顯示，可區分成兩組無交叉反應之serogroups。主要之病毒 strains 是屬於serogroup A，serogroup A 中最少可區分到9個serotypes，且毒力有明顯之差異。
病毒其有2條nucleotides，其較小為2,784bp 其encodes 為VP1，此與病毒之RNA-dependent RNA polymerase 有關 (Dobos 1995)，
另一條其大小為3,097bp其 具有2個 overlapping open reading frames. 其一較短為一約17-kDa arginine-ric 之非結構性蛋白(VP5)，另一較長為一約 106-kDa 蛋白，其順序為NH2-pVP2-VP4-VP3-COOH，其中VP2及VP3 皆為結構性蛋白(Villanueva 2004)。
人畜共通：無(No)
病原分類
2.病原分類
屬於Birnaviridae 科中 Aquabirnavirus 屬
命名沿革：重要的幾次命名歷史文獻
疾病特性
感染組織及器官：感染路徑、好發組織器官
疾病型態及流行病學：急性或慢性型態、器官傳播分佈情形
本病為一高度傳染性之病毒性疾病，感染後魚隻之死亡率(mortality)與魚品種(species)、年齡(age)、魚隻生理情況(physical condition of the fish)及所感染之病毒strain 有關(Bruslind et al 2000)，但一般其感受性會隨年齡增加而減少。
大部份有鮭魚養殖國家或地區皆有本病發生，如北美、南美、歐洲及亞洲等。病毒可經由水而達水平感染亦可經卵而行垂直感染，研究中魚卵經碘之表面消毒仍無法防止垂直感染。(Bullock 1976)
病毒可感染海水養殖魚種如 yellowtail (Seriola quinqueradiata) , turbot (Scophthalmus maximus)、dab (Limanda limanda) 、 halibut (Hippoglossus hippoglossus) 及 Atlantic cod (Gadus morhua) 。
於淡水及半淡鹹水中被偵測到有潛在感染之魚種包括 loach (Misgurnus anguillicaudatus) 、 pike (Esox lucius) 及在 Anguillidae, Atherinidae, Bothidae, Carangidae, Cotostomidae, Cichlidae, Clupeidae, Cobitidae, Coregonidae, Cyprinidae, Esocidae, Moronidae,Paralichthydae, Percidae, Poecilidae, Sciaenidae, Soleidae and Thymallidae等科中之多種魚種。(OIE 2006)
臨床症狀及病理學：
傳染性胰壞死症(infectious pancreatic necrosis)是一高度傳染性之疾病，尤其對於養於高密度下之魚苗，染病後出現體色變黑(darkening pigmentation)、腹部會腫大(distended abdomen)同時會有不正常之泳姿如螺旋狀游泳(corkscrewing or spiral swimming motion)。
於鮭魚感染IPNV後之主要病變在於胰臟(pancrease)及腸粘膜(intestinal mucosa)，胰臟主要以腺泡壞死(acinar cell necrosis )為主要病變。但有些研究中IPNV會以肝臟為其主要感染器官( target organ) (Roberts 2001)。
於其它之魚種如turbot 及 halibut 肝臟是最常被感染之主要器官，切片下可見到肝細胞之大量壞死 (hepatocyte necrosis) (Wood et al 1996.)，如成為帶原之魚隻(persistently infected fish)病毒可於其巨噬細胞(macrophages)中發現(Munro et al 2004)。
病原致病性意義：實際魚場及田間發病、抗藥性等情形
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參考文獻：
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Barlic-Maganja D, Strancar M, Hostnik P, Jencic V, Grom J. Comparison of the ef®ciency and sensitivity of virus isolation and molecular methods for routine diagnosis of infectious haematopoietic necrosis virus and infectious pancreatic necrosis virus. J Fish Dis 25: 73-80, 2002.
Blake SL, Schill WB, McAllister PE, Lee M, Singer JT, Nicholson BL. Detection and identifcation of aquatic birnaviruses by PCR assay. J Clin Microbiol 33; 835-839, 1995.
Bruslind, L. D., and P. W. Reno. Virulence comparison of three Buhl-subtype isolates of infectious pancreatic necrosis virus in brook trout fry. J. Aquat. Anim. Health 12:301–315, 2000.
Bullock G.L, Rucker RR, Amend D, Wold K, Stuckey HM. Infectious pancreatic necrosis: transmission with iodine-treated and non-treated eggs of brook trout (Salvelinus fontinalis). J Fish Res Board Can., 33: 1197-1198, 1976.
Dobos, P. Protein-primed RNA synthesis in vitro by the virion associated RNA polymerase of infectious pancreatic necrosis virus. Virology 208: 19–25, 1995.
Munro E, Gahlawat SK, Ellis AE. A sensitive non-destructive method for detecting IPNV carrier Atlantic salmon, Salmo salar L., by culture of virus from plastic adherent leucocytes. J Fish Dis 27:129–134, 2004.
Roberts RJ. Fish pathology. Third edition Harcourt Publishers Limited. P213-214, 2001.
Rodriguez Saint-Jean S, Borrego JJ, Perez-Prieto SI. Comparative evaluation of five serological methods and RT-PCR assay for the detection of IPNV in fish. J Virol Methods 97: 23–31, 2001.
Villanueva RA, Galaz JL, Valde´s JA, Jashe´s MM, Sandino AM. Genome Assembly and Particle Maturation of the Birnavirus Infectious Pancreatic Necrosis Virus. J VIROL. 13829–13838, 2004.
Wolf K, Snieszko SF, Dunbar CE, Pyle E. Virus nature of infectious pancreatic necrosis in trout. Proc. Soc. Exp.Biol. Med. 104: 105-108,1960.
Wood BD, Bruno DW, Ross K. Infectious pancreatic necrosis virus (IPNV) mortalities among farmed Atlantic halibut, Hippoglossus hippogolssus L.,in Scotland.Bull Tur Ass fish pathol.16:214-216,1996.
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