Tilapia lake virus: a threat to the global tilapia industry?

Abstract

Tilapia lake virus (TiLV) is a recently described virus affecting wild and farmed tilapines. At present, it has been reported on three continents (Asia, Africa and South America) and the number of countries where the agent has been detected is likely to increase rapidly as a result of increased awareness, surveillance and availability of diagnostic methods. Any lack of openness regarding the TiLV status of a translocating live tilapia population destined for aquaculture may inadvertently contribute to the spread of the agent. Currently, there is no cure for viral diseases in aquaculture and while vaccines and selective breeding have proved successful in reducing the severity of some viral diseases, there are currently severe knowledge gaps relating to TiLV and no effective, affordable vaccines are yet available. This paper summarizes the published scientific information on TiLV and highlights important issues relating to its diagnosis, mitigation and control measures. While there have been no scientific studies on the socio-economic impact of TiLV, it may pose a significant threat particularly to small-scale fish farmers' livelihoods and wild tilapine populations if left uncontrolled. To aid disease investigations, the authors propose case definitions for suspected and confirmed cases of TiLV infections.

Retracted: Tilapia lake virus disease: Phylogenetic analysis reveals that two distinct clades are circulating in Israel simultaneously

“…The aetiological agent(s) of the remainder of the TSC were not clear. TSC may be associated with a single or multiple factors known to cause tilapia mortality, such as streptococcal infections or external parasite infestations (Jansen et al, ). In this study, bacteriological testing and parasitological testing were not performed.…”

“…Tilapia lake virus (TiLV) is an emerging viral disease that affects several tilapia species in different countries on four continents: Asia, Africa, South and North America (Jansen, Dong, & Mohan, ; OIE, ). The virus was first described in Ecuador, affecting Nile tilapia ( Oreochromis niloticus ) fingerlings; it was diagnosed by histopathology and transmission electron microscopy and termed syncytial hepatitis of farmed tilapia (Ferguson et al, ).…”

Development of a simple and rapid reverse transcription–loopmediated isothermal amplification (RT‐LAMP) assay for sensitive detection of tilapia lake virus

“…Tilapia lake virus, a recently identified pathogen, firstly discovered in Israel (Eyngor et al, ), nowadays is being found in Asia, Africa and South America (Jansen, Dong, & Mohan, ), causes recurrent outbreaks in both wild and cultured tilapia (Ferguson et al, ). These outbreaks are characterized by significant mortality and morbidity, resulting in massive losses to tilapia industry (Tattiyapong et al, ).…”

Intragastric and intracoelomic injection challenge models of tilapia lake virus infection in Nile tilapia (Oreochromis niloticus L.) fingerlings

“…Tilapia lake virus (TiLV) is an emergent orthomyxo ‐like virus with negative sense RNA genome affecting tilapines and a few other cultured species of fish including giant gourami ( Osphronemus goramy ) (Jaemwimol et al, ; Tattiyapong, Dachavichitlead, & Surachetpong, ). Since first suspected cases emerged in tilapia in 2009 (Eyngor et al, ), outbreaks of the disease have been confirmed in at least 10 countries on four different continents (Asia, Africa, North America and South America) with evidence of continuous expansion (Eyngor et al, ; Jansen, Dong, & Mohan, ; OIE, ). TiLV infections are typically associated with high mortality, up to 90% in most cases (Dong et al, ; Surachetpong et al, ) and up to 100% in experimental trials (Behera et al, ), which emphasizes its threatens to the tilapia aquaculture industry worldwide.…”