White Spot Disease

White Spot Disease (WSSV) is a viral disease that affects shrimp, prawns, crayfish, lobsters and crabs. It is found in many Asian countries including Japan, Indonesia, Republic of Korea, Malaysia, Thailand, Vietnam, the Philippines, and India. In 1995, WSD was first reported in the US.

Signs of the disease include shell spotting from abnormal deposits of calcium salts, and occasionally a reddish discoloration. When farmed shrimp are infected, they become lethargic, stop feeding, swim slowly near the pond surface, and eventually sink to the bottom and die. Shrimp mortality can reach 100%. No treatments currently exist for WSD; therefore, shrimp farmers must rely on preventive management practices.