How Do Shrimp Get WSD?
WSSV can be transmitted in several ways:
- Shrimp become infected from other infected shrimp
- Shrimp become infected from eating infected organisms
- Shrimp are born with the virus from infected broodstock
- Shrimp get infected when they are stocked in infected ponds with carrier animals
Reports indicate that some transmission routes, such as ingestion of infected tissues, are much faster than cohabitation transmission. There is evidence the virus can be transmitted to larvae from broodstock, either from infected live and fresh feed sources, such as squid and polychaete worms, or from infected broodstock themselves.
Environmental stressors contribute to White Spot Disease outbreaks. These include factors such as rapid decline in salinity and temperature after a heavy rain, and average water temperatures below ~30°C. WSSV can survive for prolonged periods of time in the environment, where it can infect susceptible shrimp. The virus can remain infectious in seawater for up to 40 days, and in pond soil for 10 months at room temperature. If WSSV is present, infection usually occurs during the early days of stocking, especially in ponds that have not been properly prepared.
WSSV also has a wide range of potential hosts. To date, more than 93 species of arthropods are hosts or carriers of WSSV. Some unwanted species that are usually found in shrimp ponds, such as crustaceans (crabs, squilla, and copepods), polychaete, squid, and mollusks can transmit WSSV. White Spot Disease should not be confused with early mortality syndrome (EMS), also known as acute hepatopancreatic necrosis disease (AHPND), caused by Vibrio spp.
Find technical bulletins on how to prevent and control these diseases at int.biowishtech.com/resources.