Detection of piscine nodaviruses from apparently healthy wild marine fish in Korea

Abstract

Piscine nodaviruses are the causative agent of vital encephalopathy and retinopathy and wild marine fish. A total of 663 apparently healthy wild marine fish (70 species) were collected near aquaculture facilities in three different coastal areas (Donghae, Hwanghae and Namhae) of Korea. The brains of fish were examined by reverse transcriptase-polymerase chain reaction (RT-PCR) and nested PCR to detect the coat protein gene of nodavirus. Fourteen samples collected in Donghae and 80 from Hwanghae were negative for nodavirus in both RT-PCR and nested PCR tests. Two and 48 of 569 samples collected in Namhae were positive for nodavirus in RTPCR and nested PCR, respectively. Samples from 21 species have been definitively found positive: Indian perch, white croakers, spearnose grenadier, moon dragonet, blue fin sea robin, robust tonguefish, black throat sea perch, moontail puffer, silver ponyfish, yellow goosefish, daggertooth pike conger, skate ray fish, red sea bream, marbled sole, five spots flounder, chub mackerel, silver whiting, grass puffer, Japanese jack mackerel, John dory and blotched eel pout. These results indicate that nodavirus occurs at a considerably level in populations of wild marine fish in the Southern part of Korea, suggesting an importance of these fish as carriers of virus.