Table 1.
Clinical signs, pathology and diagnostic methods of single-stranded DNA viruses infecting marine and freshwater shrimp
| Disease | Etiologic agent | Year of emergence | Geographic distribution | Clinical signs | Pathology | Diagnostic methods | OIE-Listed |
|---|---|---|---|---|---|---|---|
| Infectious hypodermal and hematopoietic necrosis | Infectious hypodermal and haematopoietic necrosis virus (IHHNV) or Penaeus stylirostris densonucleosis virus (PstDNV) | 1981 | America, Asia–Pacific, Africa, Madagascar, Middle-East | Acute infection with very high mortalities occurring in juvenile of P. stylirostris (35-day-old or older) life stages. Bluish with opaque abdominal musculature at terminal-phase IHHNV infections In P. vannamei it causes cuticular deformities, specifically a deformed rostrum bent to the left or right (not always apparent in chronically infected shrimp populations). Nonspecific: reduced growth rates. Reduced food consumption, followed by changes in behavior and appearance |
Prominent intranuclear, Cowdry type A inclusion bodies, eosinophilic and often haloed, in cells of tissues of ectodermal and mesodermal origin | Gross signs, Histology, PCR, Electron Microscopy, DNA Probes, In Situ Hybridization, Bioassay | Yes |
| Hepatopancreatic parvovirus | Hepatopancreatic parvovirus (HPV) or Penaeus monodon densovirus(PmDNV) | 1983 | America, Asia–Pacific, Africa, Madagascar, Middle-East | Nonspecific gross signs: hepatopancreas atrophy, anorexia, poor growth rate, reduced preening activities (and consequential increased tendency for surface and gill fouling epicommensal microorganisms) | Intranuclear basophilic inclusion bodies, mostly in actively dividing E-and F-cells, at the distal end of the hepatopancreatic tubules | Histology, PCR, DNA Probes, In Situ Hybridization, Monoclonal Antibody (Mab) based techniques | NO |
| Spawner-isolated Mortality | Spawner-isolated Mortality Virus (SMV) | 1993 | Australia | Lethargy, failure to feed and redness of carapace and pleiopods, red feces. SMV has been associated to the Mid-Crop Mortality Syndrome (MCMS) epizootics reported in P. monodon |
Hemocytic infiltration in the gut, refractile eosinophilic granular material (REGM) in the hepatopancreas and eyestalk. Hemocytic infiltration around the tubules, pyknotic nuclei, large areas of necrosis. Spheroids in the lymphoidal organ | Histology, Electron Microscopy, Bioassay, DNA Probes, In Situ Hybridization | No |
| Lymphoidal parvo-like virus | Lymphoidal parvo-like virus (LPV) | 1991 | Australia | Nonspecific gross signs | Eosinophilic to basophilic distinctly spherical intranuclear inclusion bodies in cells of the LO, hematopoietic organs, in connective tissues of various organs and tissues, gills,. | Histology, Light and Electron Microscopy | No |