Tilapia are one of the world’s most widely consumed fish and “a mainstay of global food security and nutrition,” says the UN Food and Agriculture Organization in a warning of a viral disease that can decimate wild and farmed populations of the fish. Tilapia Lake Virus is reported in five countries in three continents — South America, Africa and Asia.
The virus is not a threat to human health although it can be deadly to the fish, says the FAO. Some 6.4 million tons of tilapia, worth $9.8 billion, were produced in 2015, making tilapia the second most important aquaculture species in terms of volume. Tilapia are omnivorous and usually resistant to disease, making them a popular fish to farm. The fish sells at reasonable prices, making it attractive to consumers. The leading tilapia producers are China, Indonesia and Egypt.
“The outbreak should be treated with concern and countries importing tilapias should take appropriate risk-management measures,” said FAO, such as stepped-up security and tests. The disease is highly contagious, with mortality rates of up to 90 percent. The route of transmission is not clear, said FAO, with research needed to see if birds, mammals or other fish can carry the virus. There are questions if frozen tilapia could harbor the virus.