Infectious Myonecrosis Virus (IMNV) in Pacific White Shrimp (Litopenaeus vannamei) in Indonesia

Penaeid shrimp culture has become a leading export fishery in Indonesia. The Pacific white shrimp (Litopenaeus vannamei) was unofficially introduced to Indonesia in 1999, and received government approval in 2001. By the end of 2007, the Pacific white shrimp was cultured in over 17 provinces. The main constraints of shrimp culture have always been diseases, especially those caused by viral agents. Taura syndrome (TS) disease was detected in Indonesia in 2002 and the disease currently affects at least ten provinces. Infectious myonecrosis (IMN) is an emerging L. vannamei disease, first detected in Indonesia in May-June 2006. IMN disease causes significant mortality in growout ponds and is characterized by acute onset of gross signs: focal to extensive whitish necrotic areas in the striated muscle, especially of the distal abdominal segments and the tail fan. The white necrotic areas redden, similar to the color of cooked shrimp. The outbreak results in elevated mortality that was initially associated with a chronic course of persistent low level mortality. To date, IMN has been detected in East Java, Bali, and West Nusa Tenggara provinces. This paper reviews studies of IMN disease of Pacific white shrimp in Indonesia: outbreaks, surveillance, diagnosis, and control measures.