Co-infection of mud crab Reovirus (MCRV) and Staphylococcus saprophyticus in giant mud crab, Scylla serrata (Forsskal, 1775)

The culture of animals in a controlled environment can be a factor in disease transmission. Mud Crab Reovirus (MCRV) and staphylococcus saprophyticus were co-infected in Scylla serrata, in a fattening pen from MGR Thittu, Cuddalore District, Tamil Nadu, Southeast coast of India. Lethargic, sluggish, partially atrophied hepatopancreas, loose gills, and discoloration of the animal characterized the spontaneously infected moribund crab. Viral invasion in the hepatopancreas with basophilic inclusion was evaluated in the histopathological studies. Molecular evidence shows reovirus infection in crab. Scanning electron microscopy reveals the presence of cocci bacteria. The 16 s RNA sequencing and phylogenetic analysis confirm the infected bacteria were Staphylococcus saprophyticus. Ultrastructural studies provided evidence for the coinfection of MCRV and Staphylococcus saprophyticus. This is the inaugural article on the co-infection of reovirus and bacteria in the mud crab Scylla serrata.