title: Epidemiology and phylogenetic analysis of Taura syndrome virus in cultured Pacific white shrimp Litopenaeus vannamei B. in Taiwan.
abstract: Taura syndrome virus (TSV) has spread worldwide, causing significant economic losses since Taura syndrome was first described in Ecuador in 1992. To determine the prevalence and impact of TSV infection on the shrimp farming industry in Taiwan, Pacific white shrimp Litopenaeus vannamei B. were collected from 220 farms between 2004 and 2006 for viral detection by reverse transcription polymerase chain reaction. Data showed that the overall TSV prevalence rate was 20% (43/220 farms). Comparing shrimp growth stages, TSV prevalence rates were 4% for postlarvae, 24% for juveniles, 24% for subadults, 32% for adults, and 5% for brooders. Among TSV-positive farms, average infection incidence was 35% in postlarvae farms, 55% in juvenile farms, 39% in subadult farms, 31% in adult farms, and 20% in brooder farms. Notably, TSV was also detected in Exopalaemon orientis H. from 1 of 10 farms. Tail fans and appendages had red pigmentation, which is characteristic of TSV infection. Of shrimp with pathological lesions, 100% had lesions on tail fans, 88% on appendages, and 80% in gills. Sequence comparison using the TSV VP1 (structural protein) gene showed that 9 isolates from the farms had 92.3 to 99.5% nucleotide sequence identity with strains in the GenBank database from Taiwan (AF406789 and AY355310) and Venezuela (DQ212790). This is the first broad epidemiological study of TSV infection in L. vannamei in Taiwan.
authors.affiliation: Graduate Institute of Animal Vaccine, National Pingtung University of Science and Technology, Pingtung 91201, Taiwan.
authors.forename: LiTing
authors.initials: L
authors.lastname: Cheng
authors.forename: Wen-Hui
authors.initials: WH
authors.lastname: Lin
authors.forename: Pei-Chyi
authors.initials: PC
authors.lastname: Wang
authors.forename: Ming-An
authors.initials: MA
authors.lastname: Tsai
authors.forename: Ping-Yueh
authors.initials: PY
authors.lastname: Ho
authors.forename: Jung-Pin
authors.initials: JP
authors.lastname: Hsu
authors.forename: Red-Shyong
authors.initials: RS
authors.lastname: Chern
authors.forename: Shih-Chu
authors.initials: SC
authors.lastname: Chen
mesh_terms: D000818:Animals; D001483:Base Sequence; D008969:Molecular Sequence Data; D033561:Penaeidae; D010802:Phylogeny; D012328:RNA Viruses / Q000235:genetics* / Q000302:isolation & purification; D013624:Taiwan