Type MBV and SEMBV has detected widespread across the pond in Indonesia. The disease attacks the shrimp aged 1-2 months has been stocking. MBV attack is marked by changes in hepatopancreas which became yellowish because of damage. The case hit since 1998 with a death rate of more than 90% within 2 weeks after the symptoms of common assault. While the disease caused by SEMBV marked by the onset of white patches measuring 0.5 to 2.0 mm on the carapace to spread to the tail end.
The white patches are incurred as a result of abnormal calcium salt depasit by kutikular epidermal layer. Signs attack YHV in shrimp ponds yellowish head. This type of virus, the host range and the resulting common clinical signs can be seen in Table 1.
Table 1. Type of virus, host range and general clinical signs caused.
Done in different ways. Starting with a virus isolation followed by identification through bioassay, histopathology, electro microscope, and Polymerase Chain Reaction (PCR). However the method common diagnoses in some laboratory is bioassay and PCR. In the bioassay techniques in addition to knowing the main pathogens, can also be obtained information several biological properties of pathogens such as:
1) The transmission mechanism horizontally
2) Virulence and the incubation period
3) Host-specific and non-specific
A common technique is done is postulate River Test which is through the technique of cohabitation with fish Mixing the source of infection to healthy fish within a certain time and techniques of artificial infection through injecting KHV virus particles. On Cohabitation technique, the ratio of the source of infection and the fish are healthy fish; 1: (4-8) within 7-10 days.