Whiteleg shrimp, Litopenaeus vannamei, with clinical sign of muscle opaqueness with reddish colour at the distal abdominal segments were observed in farms located in West Bengal State, India. The mortality of shrimp in all disease outbreak ponds ranged from 20% to 50%, and mortality increased gradually. The RT ‐ PCR assay of these samples using primer sets specific to infectious myonecrosis virus ( IMNV ) revealed its presence...