Spring Viremia of Carp Firas Abdul Malik M.Sc. Fish Biology
Domain: Virus Group: "RNA viruses" Order: Mononegavirales Family: Rhabdoviridae Genus: Vesiculovirus Species: spring viremia of carp virus Source: (Zhang, et al., 2009).
This viral disease is caused by Rhabdoviruscarpio, a bullet-shaped RNA virus (Sano, et al., 2011).Spring viremia of carp is systemic and acute and highlycontagious viral disease of carp (Cyprinus carpio) andperhaps other cyprinids (Basic, et al., 2009). It usuallyoccurs and causes high mortality at temperatures of (11-13C)-(Emmenegger & Kurath, 2008), typically astemperatures rise in spring (Carstens,2010). SVC is alsocalled (Infectious Dropsy of Carp, Infectious Ascites,Hydrops, Red Contagious Disease, Rubella,Hemorrhagic Septicemia) (Sano, et al., 2011). Thedisease can cause up to 100% mortality and affects allages of fish. It has resulted in significant economiclosses to fisheries in all the World. ( Haghighi, et al.,2008). 3
History of the Virus: The disease was initially diagnosed in Yugoslavia(Fijan, et al., 1971). Since then, it has been identified inother European countries, Russia, Middle East, UnitedStates and United Kingdom. (Sano, et al., 2011). Mortalityhas reached 70% in yearling carp from Europeanpopulations. Adult fish can also be affected but to a lesserdegree. 4 Figure (1): SVC Virus (bullet like Shape)
5. SKIN DARKENING 6. PALE GILLS Source: (Zhang, et al., 2009). Figure (8) Figure (9): Spring viremia of carp. Pale gills with hemorrhage in experimentally infected (a) carp compared with gills in control fish (b). Basic, et al., (2009).
7. HEMORRHAGES 8. HEMORRHAGES IN MUSCLE IN SWIM BLADDER Source: (Dixon, 2008). Source: (Sano, et al., 2011). Figure (10) Figure (11)
9. SWOLLEN STOMACH 10. HISTOPATHOLOGICAL SECTION OF GILL IN CARP INFECTED WITH SVC Source: (Basic, et al., 2009). Source: (Dixon, 2008). Figure (12) Figure (13)
11. FISH KILLS Figure (14) : Salmon Hatchery, Washington – (Coho salmon killed by SVC virus).Source: (Dixon, 2008).
Fish behavior after infection:1. Appear lethargic.2. Slowed respiration.3. Loss of equilibrium.4. Separate from the shoal.5. Tilting to one side.6. Lying on bottom of pond.7. Gather at the water inlet or sides of apond. (Sano, et al., 2011); (Carstens, 2010); (Basic, et al., 2009); (Soliman , et al., 2008); (Emmenegger & Kurath, 2008).
Fish types which affected byvirus.1.Common carp. 2.Silver carp.3.Grass carp. 4.Goldfish.5.Koi carp. 6.Crucian carp.7.Bighead carp. 8.Catfish.9.Orfe. 10.Tench.11.Salmon. (Zhang,et al., 2009).
Table (1): Virus transmission and Infection degree(Zhang,et al., 2009).Transmission 1. Direct transmission via water, 2. mechanical transmission via parasites & birdsInfection Depends on:degree 1.Age. 2.Water Temperature. 3.Other Stress Factors.
Table (2): Control and treatment of disease (Carstens,2010).Prevention 1. Depopulation and disinfection. 2. Continuous rearing at 20-22 C.& 3. Hygienic measures. Beware of potential carriers. Vaccination isControl at an experimental stage.Treatment Raise of water Temperature to above 20 C.
Incubation period: The incubation period of SVC depends on:1. Water temperature,2. Species,3. Age,4. Condition of the fish,5. Quantity of virus, and on6. Certain environmental conditions. (Sano, et al., 2011); (Adel, et al., 2008); (Basic, et al., 2009); Table (4): Effect of temperature fluctuation onmortality rate (Sano, et al., 2011). Temp. % Mortality Period (days) 10-12 C 90% 2-4 12-16 C 75% 4-7 16-17 C 60% 7-15 17-26 C 30% 15-21
Figure (15): Influence of water temperature on SVCV (spring viremia of carpvirus)-infection of carp Cyprinus carpio leading to virus multiplication (10-12 C) or to production of antibodies (20-22 C). SPF carp (25-30g) were intraperitoneally infected with SVCV. Infected fish kept at 10-12 C and 20-22 Cwere analyzed for values of virus, antibodies and death . Source: (Dixon,2008).
Conclusion:1. Disease outbreaks in carp generally occur between 11- 17 C.2. Disease rarely occur below 10 C.3. Small fish more affected than older fish.4. Fish mortalities decline as the temperature exceeds 22 C.5. In carp, the disease is often observed in springtime (hence the common name for the disease).6. Rare in countries having cold winters.7. It is believed that the poor condition of the over- wintered fish may be a contributory factor in disease occurrence.8. The disease can occur in fish in quarantine following the stress of transportation, even though there has been no evidence of virus in the fish prior to transportation.
ReferencesAdel, H. K.; Moigan, B.; Zarrin, S. & Bahram, K. (2008). The First Report of Spring Viraemia of Carp in Some Rainbow Trout Propagation and Breeding by Pathology and Molecular Techniques in Iran. 2013 Science Alert. All Rights Reserved. Asian Journal of Veternary Advances.3 (4): 263-268. Islamic Azad University of Iran,Tehran.Basic, A.; Schachner, O.; Bilic, I. & Hess, M. (2009). Phylogenetic analysis of spring viraemia of carp virus isolates from Austria indicates the existence of at least two subgroups within genogroup Id. Dis. aquat. Org., 85, 31– 40.Carstens, E.B. (2010). Ratification vote on taxonomic proposals to the International Committee on Taxonomy of Viruses (2009). Arch. Virol., 155, 133–146.Dixon, P.F. (2008). Virus diseases of cyprinids. In: Fish Diseases, Vol. 1. Eiras J.C., Segner H., Wahli, T. & Kapoor, B.G. eds. Science Publishers, Enfield, New Hampshire, USA, 87–184.Emmenegger, E.J. & Kurath, G. (2008). DNA vaccine protects ornamental koi (Cyprinus carpio koi) against North American spring viremia of carp virus. Vaccine, 26, 6415–6421.
ReferencesFijan, N.; Petrinec, Z.; Sulimanovic, D.; Zwillenberg, L. (1971). Isolation of the viral causative agent from the acute form of infectious dropsy of carp, Veterinarski Arhiv 41:125-138.Haghighi Khiabanian Asl A., Azizzadeh M., Bandehpour M., Sharifnia Z. & Kazemi B. (2008). The first report of SVC from Indian carp species by PCR and histopathologic methods in Iran. Pakistan J. Biol. Sci., 11, 2675–2678.Sano, M., Naki, T. and Fijan, N. (2011) Viral Diseases and Agents of Warm water Fish. In: Fish Diseases and Disorders, Volume 3: Viral, Bacterial and Fungal Infections, 2nd edition (eds. Woo, P.T.K. and Bruno, D.W.), CABI, Wallingford, UK. Pp. 166-244.Soliman M.K., Aboeisa M.M., Mohamed S.G. & Saleh W.D. (2008). First record of isolation and identification of spring viraemia of carp virus from Oreochromis niloticus in Egypt. 8th International Symposium on Tilapia in Aquaculture 2008, 1287–1306.Zhang, N.Z.; Zhang, L.F.; Jiang, V.N.; Zhang, T. & Xia, C. (2009). Molecular analysis of spring viraemia of carp virus in China: A fatal aquatic viral disease that might spread in East Asian. PLoS ONE, 4, pp 1–9.