Prevalence of white spot syndrome virus in wild crustaceans along the coast of India.

Crustacean samples comprising of shrimps, crabs and squilla were collected from various landing centres and local fish markets of Kolkata, Chennai, Thiruvananthapuram, Mangalore and Mumbai along the east coast and west coast of India, Nested polymerase chain reaction (PCR) was employed for screening the samples for white spot syndrome virus (WSSV). A total of 89 crustacean samples were examined, which comprised of 40 shrimps, 36 crabs and 13 squilla samples. The results indicate that the wild-caught marine shrimps such as Penaeus monodon, Heterocarpus sp., Aristeus sp., Parapenaeopsis stylifera, Metapenaeus dobsoni, M. elegans and Squilla sp. carry WSSV. This virus could be detected in apparently healthy crabs such as Scylla serrata, Portunus sanguinolentus, P. pelagicus, Calappa lophos, Charybdis hoplites, C. lucifera, C. cruciate and Pseudograpsus intermedius. The virus was also found to be present in the freshwater prawn Macrobrachium rosenbergii, collected from the fish market. Sensitivity of detection of WSSV by PCR improved greatly, with PCR primers yielding amplicons of smaller size. Marine shrimps such as Heterocarpus sp., Aristeus sp., Metapenaeus elegans and crabs such as C. hoplites are being reported as carriers of WSSV.