Tilapia lake virus is a newly emerging virus that is associated with significant mortalities in farmed tilapia. This fact sheet describes the threat to industry, clinical signs, diagnosis, risk factors, prevention and control options and actions that must be taken to minimise the impact of this disease on the global tilapia aquaculture industry. All countries with a tilapia industry must be vigilant and act quickly to investigate cases of mortalities in farms.

Since the first discovery of the virus in Israel in 2014, cases have been reported in Columbia, Ecuador, Egypt and Thailand. Now that screening tools are available and can be accessed by fish disease diagnostic/research labs, the number of reported TiLV cases is expected to rise.

The emergence of TiLV is the first-ever major disease epidemic reported in tilapia aquaculture, and puts the global industry at risk. Irresponsible trade in live aquatic animals and intensification without biosecurity considerations significantly compound this risk.