Surveillance for Viral Diseases of Farmed Fish and Shrimp - Taiwan, 2012

C Tu*, SH Cheng, JC Tsai, HJ Tsai

Animal Health Research Institute, Council of Agriculture, Executive Yuan

Abstract

A total of 6,101 specimens collected from cultured aquatic animals were submitted for a passive diseases surveillance program in 2012. For marine fish, of the 1,121 cases with a viral etiology in grouper, 47(4.2%) were caused by red seabream iridovirus, 20 (1.8%) were caused by grouper iridovirus, 2 (0.2%) were caused by infectious spleen and kidney necrosis virus and 50 (4.5%) were caused by nervous necrosis virus. Of the 175 cases of cobia disease, 29 (16.6%) were caused by red sea bream iridovirus, and 1 (0.6%) was caused by nervous necrosis virus. In freshwater fish, among the 710 cases of koi disease, 83 (11.7%) were caused by koi herepesvirus. Among the 39 cases of eel disease, 18 (46.2%) and 8 (20.5%) were caused by aquabirnavirus and anguillid herpesvirus, respectively. Among the 1,692 cases of ornamental shrimp disease examined, 21 (1.2%) were caused by infectious hypodermal and hemapoietic necrosis virus, 93 (5.5%) were caused by white spot disease virus, 17 (1.0%) were caused by yellow head disease virus and 5 (0.3%) were caused by Taura syndrome virus. Regarding the grouper disease ctaegory, the percentage of cases associated with red seabream iridovirus (a foreign invading iridovirus) increased substantially, compared to those associated with grouper iridovirus (a domestic iridovirus).

Keywords: fish virus, shrimp virus, disease surveillance.