The molecular detection of Taura syndrome virus emerging with White spot syndrome virus in penaeid shrimps of Thailand

This study is to investigate the outbreak of the Taura syndrome (TS) in penaeid shrimps of Thailand. Following the outbreak in 2003, the Taura syndrome virus (TSV) was detected in two closely related penaeids; the Pacific white shrimp, Penaeus vannamei, and the black tiger prawn, Penaeus monodon. Multiple viral infections were detected, we found that the TSV-infected P. vannamei also presented evidence of the White spot syndrome virus (WSSV) as evidenced by histological examination and molecular diagnostic methods. Infections of TSV and WSSV were investigated over a period of ten months between October 2003 and July 2004. TSV infection in shrimps was diagnosed by RT-PCR using the OIE recommended 9195/9992 primers. Positive shrimp gave the expected amplicon of 231 bp. We also amplified and sequenced a fragment of the vp1 gene (354 bp). The pairwise comparisons of vp1 revealed that Thai TSV was phylogenetically related to the Taiwanese strains (98.3% identity).