First generic one step real-time Taqman RT-PCR targeting the RNA1 of betanodaviruses

142

115

Viral encephalopathy and retinopathy (VER), otherwise known as viral nervous necrosis (VNN), is a major devastating threat for aquatic animals. Betanodaviruses have been isolated in at least 70 aquatic animal species in marine and in freshwater environments throughout the world, with the notable exception of South America. In this review, the main features of betanodavirus, including its diversity, its distribution and its transmission modes in fish, are firstly presented. Then, the existing diagnosis and detection methods, as well as the different control procedures of this disease, are reviewed. Finally, the potential of selective breeding, including both conventional and genomic selection, as an opportunity to obtain resistant commercial populations, is examined.

Section: Diagnosis/detectionmentioning

confidence: 97%

“…; Baud et al . ), and an optimized loop‐mediated isothermal amplification has been developed to detect NNV in Epinephelus septemfasciatus (Hwang et al . ).…”

Section: Diagnosis/detectionmentioning

confidence: 99%

Viral encephalopathy and retinopathy in aquaculture: a review

Doan

Vandeputte

Chatain

et al. 2016

142

115

“…) employing amplification primers specific to RNA1 or RNA2 (Baud et al . ). By taking advantage from the virus binding to polystyrene, some attempts have been made to develop enzyme‐linked immunosorbent assays (ELISAs) to detect VERv in biological fluids or other samples, as it is an easy, inexpensive and an accessible test.…”

Section: Introductionmentioning

confidence: 97%

Quantitative immunoenzymatic detection of viral encephalopathy and retinopathy virus (betanodavirus) in sea bass Dicentrarchus labrax

Nuñez-Ortiz

Stocchi

Toffan

et al. 2015

Viral encephalopathy and retinopathy disease caused by betanodavirus, genus of the family Nodaviridae, affects marine, wild and farmed species including sea bass, one of the most important farmed species in Europe. This work describes a reliable and sensitive indirect ELISA assay to detect betanodavirus in biological samples using a polyclonal antiserum (pAb 283) against the 283/I09 virus strain, the most common red-spotted grouper nervous necrosis virus (RGNNV) genotype in the Mediterranean area, and a capture-based ELISA using a monoclonal antibody (mAb 4C3) specific to a common epitope present on the capsid protein. Using adsorbed, purified VERv preparation, the detection limit of indirect ELISA was 2 μg mL(-1) (3 × 10(5) TCID50 per mL), whereas for capture-based ELISA, the sensitivity for the antigen in solution was 17 μg mL(-1) (35 × 10(5) TCID50 per mL). The capture-based ELISA was employed to detect VERv in brain homogenates of in vivo infected sea bass and resulted positive in 22 of 32 samples, some of these with a high viral load estimates (about 1.1 × 10(8) TCID50 per mL). The ELISA system we propose may be helpful in investigations where coupling of viral content in fish tissues with the presence of circulating VERv-specific IgM is required, or for use in samples where PCR is difficult to perform.

“…Currently, molecular techniques based on the amplification of genetic material in samples such as qPCR have been developed and validated for detection of other fish viruses (Ciulli et al., ; Dalla Valle et al., ; Starkey et al., ). A one step, real‐time RT‐PCR was developed to detect the RNA1 genomic sequence of the betanodavirus infection in various fish species including tilapia (Baud et al., ). The qPCR method offers multiple advantages over other diagnostic methods such as a rapid result within a short period, allowing direct quantification of pathogens in tissue samples, being highly specific to the target viral pathogen.…”

Section: Discussionmentioning

confidence: 99%

Development and validation of a reverse transcription quantitative polymerase chain reaction for tilapia lake virus detection in clinical samples and experimentally challenged fish

Tattiyapong

Sirikanchana

Surachetpong

2017

Tilapia lake virus (TiLV) is an emerging pathogen associated with high mortalities of wild and farm-raised tilapia in different countries. In this study, a SYBR green-based reverse transcription quantitative polymerase chain reaction (RT-qPCR) assay targeting segment three of the virus was developed to detect and quantify TiLV in clinical samples and experimentally challenged fish. All 30 field samples with clinical signs and history consistent with TiLV infection were positive for TiLV as detected by the developed RT-qPCR method. The RT-qPCR technique provided 100 and 10,000 times more sensitive for virus detection than those offered by the RT-PCR and virus isolation in cell culture methods, respectively. The detection limit of the RT-qPCR method was as low as two viral copies/μl. Moreover, the RT-qPCR technique could be applied for TiLV detection in various fish tissues including gills, liver, brain, heart, anterior kidney and spleen. Significantly, this study delivered an accurate and reliable method for rapid detection of TiLV viruses that facilitates active surveillance programme and disease containment.