Molecular, histopathologic and electron microscopic analysis of white spot syndrome virus in wild shrimp (Fenneropenaeus indicus) in the coastal waters of Iran

Viral Shrimp Diseases Listed by the OIE: A Review

“…Among various diagnostic methods, PCR is used as the most sensitive method by which to detect WSSV infection, by targeting the VP28 gene [ 27 ] ( Table 5 ). There are several PCR methods available for the diagnosis of WSSV, such as one-step PCR, nested-PCR, and real-time PCR [ 54 ]. One-step PCR can be used to detect the presence of WSSV in shrimp with high levels of infection, and nested-PCR can increase the sensitivity level when compared to one-step [ 55 ] to detect low levels of infection in the broodstock, nauplii, post-larvae, and juvenile stages [ 54 ].…”

“…There are several PCR methods available for the diagnosis of WSSV, such as one-step PCR, nested-PCR, and real-time PCR [ 54 ]. One-step PCR can be used to detect the presence of WSSV in shrimp with high levels of infection, and nested-PCR can increase the sensitivity level when compared to one-step [ 55 ] to detect low levels of infection in the broodstock, nauplii, post-larvae, and juvenile stages [ 54 ]. Therefore, the pathogen can be easily detected using one-step PCR when clinical signs such as lethargy, reduced feeding and white spots on the exoskeleton appear, but can only be detected by nested-PCR when asymptomatic [ 55 ].…”

“…WTD is caused by Mr NV ( Macrobrachium rosenbergii nodavirus) which is accompanied by another virus, XSV (extra small virus) [ 142 ] ( Table 1 ). Mr NV is a small icosahedral with non-enveloped two single-stranded RNA virus (RNA1: size 2.9 kb, RNA2: size 1.26 kb) approximately 26–27 nm in diameter and was observed in the cytoplasm of connective cells classified into the family Nodaviridae, which consists of two genera, Alphanodavirus and Betanodavirus, Nodaviruses have T = 3 capsids of a single polypeptide that is 43 kDa [ 54 , 144 ]. The phylogenetic tree obtained from RdRp demonstrates that Mr NV is more related to alphanodaviruses, whereas in the capsid-based phylogenetic tree, Mr NV and Pv NV (a second prawn nodavirus; Penaeus vannamei nodavirus) are more closely related to betanodaviruses ( Mr NV and Pv NV: 69% homology in the capsid protein genes) [ 150 , 151 ].…”

“…RNA-1 included two nonstructural proteins such as A protein [RNA-dependent RNA polymerase (RdRp) containing approximately 1000 amino acids (ca. 100 kDa)] and B protein [13 kDa encoding 30 region of RNA-1 (2725–3126 nucleotides)], whereas RNA-2 included a single polypeptide in the capsid protein [ 54 ]. XSV genomic nucleotide sequencing indicated that it consisted of 796 nucleotides such as the coding sequence of the capsid protein CP-17 (17 kDa) and CP-16 (16 kDa) [ 137 ].…”

Investigation of white spot syndrome virus (WSSV) infection in wild crustaceans in the Bohai Sea

“…The prevalence of WSSV caused huge economic losses to the shrimp farming industry of the world. Moreover, in addition to farmed crustaceans, the presence of WSSV in wild shrimps had also been reported by different researchers (Hossain et al, 2001;Jang et al,2009;Marques et al,2011;Soo-Jung et al, 2010;Gholamhosseini et al, 2020;Mondal & Mandal, 2020). However, there have been no systematic investigation on the prevalence of WSSV in marine ecosystems up to now.…”