68 MARCH 2023 • WORLD AQUACULTURE • WWW.WAS.ORG Other prevention methods include good management practices such as rapid removal of moribund and dead fish, together with the safe disposal of removed fish. Conclusion Tilapia lake virus is a newly emerging, single-stranded RNA virus that affects both wild and farmed tilapias, with very high mortality rates of up to 90 percent, thus posing a severe threat to the global tilapia industry. Since it was first reported in 2014 in Israel, it has been reported in many other countries in Asia, Africa and South America. It mainly affects the fingerling and juvenile stages of tilapia, although adult stages are also reported to be affected. The main clinical signs and symptoms of TiLV infected tilapias are ocular alterations (e.g., lens opacity, ruptured lens and bulging eyes), scale protrusions, lesions on the skin, ulcers, loss of appetite, sluggishness, pale gills, discoloration and abnormal behaviors, such as swimming at the surface or reduced schooling behavior. Currently, no protocol and medications are available to prevent or treat TiLV disease. Therefore, stress on the tilapia farms should be minimized by following good sanitary and biosecurity practices. More research should be carried out to produce genetically improved tilapia with more resistance to TiLV and to develop a vaccine that could offerlong term prospects for managing the disease. Notes Soibam Ngasotter, Soibam Khogen Singh and Pradyut Biswas, College of Fisheries, Central Agricultural University (Imphal), Lembucherra-799210, India Corresponding author: khogensingh.aqc.cof@cau.ac.in References Amal, M.N.A., C.B.Koh, M. Nurliyana, M. Suhaiba, Z. 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The main clinical signs and symptoms of TiLV infected tilapias are ocular alterations (e.g., lens opacity, ruptured lens and bulging eyes), scale protrusions, lesions on the skin, ulcers, loss of appetite, sluggishness, pale gills, discoloration and abnormal behaviors, such as swimming at the surface or reduced schooling behavior. Currently, no protocol and medications are available to prevent or treat TiLV disease.
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