Transmission, virulence, and recovery coefficients of white spot syndrome virus (WSSV) and Taura syndrome virus (TSV) infections in Kona stock Litopenaeus vannamei
Coastal Sciences, Gulf Coast Research Laboratory
We used an experimental procedure based on a mathematical epidemiology model to compare the transmission, virulence, and recovery coefficients of Litopenaeus vannamei (Kona stock) exposed to white spot syndrome virus (WSSV) or Taura syndrome virus (TSV). The procedure involved exposing 12 susceptible shrimp to a single WSSV- or TSV-infected shrimp cadaver for 14 h and then isolating the exposed shrimp individually for 5 d to determine the number of infections and deaths. The L. vannamei used in the experiments were from the original unselected, highly susceptible population of shrimp maintained by the U.S. Marine Shrimp Farming Program. Two experiments were conducted, the results from which were similar. The estimated transmission coefficients were 0.61 for the TSV exposures and 0.41 for the WSSV exposures. The estimated virulence coefficient was higher for the WSSV exposures (0.37) than for the TSV exposures (0.12). In contrast, the estimated recovery coefficient was higher for the TSV exposures (0.10) than for the WSSV exposures (0). For the WSSV-exposed shrimp, most animals died 24-48 h postexposure; for the TSV-exposed shrimp, most died 48-96 h postexposure.
JOURNAL OF AQUATIC ANIMAL HEALTH
Lotz, J. M.
(2003). Transmission, virulence, and recovery coefficients of white spot syndrome virus (WSSV) and Taura syndrome virus (TSV) infections in Kona stock Litopenaeus vannamei. JOURNAL OF AQUATIC ANIMAL HEALTH, 15(1), 48-54.
Available at: http://aquila.usm.edu/fac_pubs/4388