Development and applications of the real-time polymerase chain reaction method for rapid quantitative detection of the newly emerged novel genotype of Decapod hepandensovirus 1 in Penaeus vannamei

Decapod hepandensovirus 1 (decapod hepanhamaparvovirus [DHPV]) is a member of the family Parvoviridae. The natural host of DHPV includes various captured or cultured penaeid shrimp species. The virus infects the host's hepatopancreas, leading to disturbance in digestion and reduced shrimp yields, causing substantial economic losses. Recently, the emergence of a new DHPV genotype (nDHPV) in Penaeus vannamei has been reported, and considering that the shrimp is one of the most extensively cultivated species in the global aquaculture industry, the development of diagnostic methods for the virus is urgent. To address the need for accurate detection and diagnosis of nDHPV, this study presents a diagnostic quantitative polymerase chain reaction method designed to detect the virus currently prevalent in P. vannamei. The assay was applied to various nDHPV-positive samples to confirm its practical utility and quantify the prevalence of nDHPV. Moreover, the analytical specificity of this assay to other several shrimp pathogens was also addressed. To the best of our knowledge, this study represents the first report of a quantitative method based on nDHPV identified from P. vannamei. The findings provide valuable insights into the pathogenesis and epidemiology of nDHPV in this economically significant species.