Epidemiological status of Taura syndrome and Infectious myonecrosis viruses in Penaeus vannamei reared in Pernambuco (Brazil)

Several viral diseases of cultured Penaeus vannamei, threaten the sustainability of shrimp farming industries worldwide. Taura syndrome virus (TSV) is considered one of the most harmful pathogens in theAmericas, with cumulative mortalities reaching 40 to 95%. Another virus, named Infectious myonecrosis virus (IMNV), was first identified in P. vannamei reared in Northern Brazil in 2004. In this study, we investigated the epidemiological status of TSV and IMNV in cultured shrimp by reverse transcriptase-polymerase chain reaction (RT-PCR) in Pernambuco state. Eleven commercial farms were randomly sampled between August and December of 2004, out of 14 existing farms in the state.Within each farm, ponds were randomly sampled and 10 shrimpswere testedwithin each of them.Atotal of 505 individuals samples were RT-PCR tested. None was positive for TSV, suggesting that the virus was not present in the study population, which is consistent with the absence of clinical reports. Nine out of 11 farms were positive for IMNV, which should be considered alarming and strengthens the need for establishing monitoring programs at the national level. These results provide new insights into the epidemiological status of both diseases and may contribute to the development of a national biosecurity plan