Vaccines in Fish

Aquaculture Fisheries Development :
In line with the development of a disease that attacks the human body, as well as development occurs diseases that attack fish. Initially the disease that attacks the fish was caused by endoparasites, ectoparasites and bacteria. however, due to the changing environment, whether caused by human activity and due to the dynamic changes of nature itself, the virus began to attack the fish. Attacks by this virus disease, tragically led to mass death.
There are some viruses that attack fish and become famous such as:

1.  KHV (Koi Herpes Virus) attacks first detected in 1998 in Indonesia, 1999 in Israel and in the United States that caused mass mortality 80-100% of carp and generally the conditions of temperature 22-27 C (72-81 F). Signs attacked by KHV fish showed symptoms following the sudden loss of appetite, fish movement is not normal, not normal breathing (operculum move fast), white patches on the gill lamella which further eroded and eventually decay, bleeding on the fins and body followed by a blister wounds. Death occurs between 1-5 days of initial symptoms
2.  CCVD (Channel Catfish Virus Diseases) is an acute infection by the virus Herpes haemorhagik. This disease can cause high mortality, sometimes reaching almost 100% in young Ictalurus punctatus. Natural host is attacked Channel catfish (Ictalurus punctatus) is usually aged less than 4 months. The results of the experiments indicate infection with this virus can attack white catfish (I. catus), blue catfish (I. furcatus), and walking catfish (Clarias batrachus). Clinical signs / pathology of this disease that can be observed include loss of body balance , moving in circles and hanging vertical, stand mat (exophthalmus), abdominal distention or inflated.
3. Spring Viraemia Of Carp (SVC) is a disease / infection by haemorhagic acute viral and infectious diseases, which attack fish groups Cyprinids and more specifically on the common carp, Cyprinus carpio. This disease usually occurs in spring (Spring) and the cause of death at all ages. Common carp is the main host and the virus can attack adult and young fish. It was also reported that the virus had also isolated from the others Cyprinids groups. Silver carp, Bighead carp (Aristichthys nobilis) and Crucian Carp (Carassius auratus). Experimentally Fry Pike (Esox Lucius) and larvae, fry of carp, Grass carp (Ctenocephalon idella) and Guppies (Lebistes reticulata). Clinical signs and pathological SVC attacks include fish congregate at the outflow, the color becomes darker fish, bleeding / petekiae haemorhage, prominent eyes (exophthalmus), abdominal dropsy, usually found also fibrinous peritonitis and ctarrhal or necrotic enteritis. While Swimbladder Inflammation (SBI), which is identical with the virus SVC virus, may exhibit symptoms of clinical / pathological are losing weight and balance, color becomes darker / change, degeneration / bleeding on the walls of air bubbles (swimbladder).
4. Infectious Pancreatic Necrosis (IPN) is a viral disease of an acute and highly contagious, especially the attacking group Salmonis fish. Against the young fish are cured (survivors) are resistant to the disease but can be carriers of infection (carrier) lifetime. IPN has been reported as an endemic disease area / location of trout fishing in at least ten European countries, including Scandinavia and the United Kingdom, as well as in North America and Jepang.IPN can invade a variety of host origin well enough fresh water or sea water and Shellfish laut.Virus IPN possibility was first reported in France in 1965. Likewise in Denmark, IPN virus has been identified as virologic in 1968. IPN disease by non-salmonid species have also been identified and the virus has also been isolated from a variety of non-salmonid species and isolation of the virus was first reported by Sonstegard. in 1972 derived from fish "Yearling White Suckers" (Catastomus comersoni) in Canada. In Germany virus isolated from grayling (Thymallus Thymallus), barbell (Barbus Barbus), Pike (Esoxlucius) and Carp (Cyprinus carpio). In Northern Ireland, IPN virus isolated from Goldfish (Carassius auratus), Discuss Fish (Symphysodon Discus) and Bream (Abramis Brama). In the UK (England) isolated from Carp (Cyprinus carpio) and Crucian Carp (Carassius auratus).Similarly in Japan IPN virus isolation obtained dariEuropean eels (Anguilla anguilla) and Japanese eels (Anguilla japonica) and named Eels Virus European (EVE). IPN Transmission can occur vertically, the virus is present in the egg, or horizontal, through water, urine , faeces, or through sexual secretions of fish dead / sick consumed by other fish. Generally fish cured (survivors / carriers) can be non-clinical carriers or carriers of disease, possibly for life, and carriers will also act as a reservoir of the virus to other fish that previously have not been infected. Additionally IPN relatively short incubation period, between 3-5 days before clinical signs and death occur. Factors such as the age of the host, low temperature and fish species can prolong the incubation period. In case / outbreak, first signs of a sudden death and usually the first affected are the young fish. Clinical signs may vary, ie the color becomes dark fish, moving around, exophthalmus (bulging eyes), abdominal bloating and fluid are visceral, bleeding in the lower abdomen / ventral included in the fins, liver and spleen was pale and enlarged, not there is food in the stomach and intestines usually mucoid exudate containing a yellowish or whitish. Lymphocystis is caused by a virus which is considered the oldest and most known viruses in fish, although the virus was isolated and grown in inoculant new network in 1966.
5. Lymphocystis (LD) occurs in many countries and at least 97 species of teleost fish species ever had the disease, an infection that is generally prevalent, chronic and malignant tumors are caused by iridovirus. The disease attacks many species of both freshwater fish, marine, farmed fish or wild fish, has also been found in marine ornamental fish fish quarantine region (outside the country). Transmission can occur directly or indirectly such as through contaminated water virus, through food and through injections.
   But where transmission is the main outer skin surface, including the gills. Clinical signs / pathology of this virus attack is the thickening (hypertrophy) of the connective tissue cells that give rise to bumps on the skin area (nodules) on the fins or skin; may occur on a one-on-one or in groups. In histopathologic in the fibrocytes / infected cells were clearly visible presence of hypertrophy with hyaline and basophilic intracytoplasmicinclusions capsul.
6. Disease Infectious haematopoietic necrosis (IHN) is an illness that is acute and systemic. This disease attacks the Rainbow trout (Salmo gairdneri), Chinook slmon (Oncorrhynchus tshawytscha), Sockeye salmon (O. uninformed). Target cells IHN disease is especially the blood-producing organs kidney and spleen face. Clinical signs of this disease include infected fish appear lethargic, gathered at the edge of the pond, darker, anemia, exophthalmia, scoliosis, lordosis, abdominal swelling, bleeding base of the pectoral fin and pelvic fin, bleeding under the skin; kidneys, spleen and liver looks pale, the abdomen filled with fluid and an empty bowel, bleeding spots in the intestinal adipose tissue.
7. Viral Nervous Necrosis (VNN) is a viral disease that infects the larvae and juvenile fish stadia sea and is a disease that is harmful to the fish hatchery business. Symptoms that appear on VNN infected fish varies according to the stadia or the age of the fish. Age of fish under 20 days when infected but show no clinical symptoms decreased appetite. Fish aged 20-40 days showed abnormal swimming behavior of the fish swimming near the surface of the water and many die at the bottom of the tub. For fish aged 2-4 months, while the placement of the cages infected fish appear stationary / bottom bed nets. While fish aged 4 months to over look the swimming float above the water surface with a magnification bubble pool. In Indonesia VNN assault case was first identified in hatchery snapper in East Java in 1997. Then in 1998 cases of death caused by VNN found in grouper duck (Cromileptes altivelis) with a mortality rate approaching 100%. It commonly infects the larvae to juvenile stadia and attack the nervous system of the eye and the brain organ that is characterized by vakuolasi, with symptoms that are specific enough for the fish to swim manifest behavior that is not normal and the fish are generally silent on the bottom of the pool

The conclusions obtained from the types of the virus that attacks the fish as described above obtained the reasons that the disease must be prevented because it is very difficult to treat are:

1. The disease caused by this virus will cause mass death quickly
2. Parent farmed fish that have been infected by the virus has potential as carriers of disease agents to offspring
3. Fish production is generated in the cultivation and taking in the sea obtained from the potential to cause disease in humans 

The disease caused by this virus can be dealt with biosecurity. Biosecurity is defined as a series of efforts to prevent or reduce the chance of entry of the disease into the farming system and prevent its spread from one place to another are still free. The basic principle is to apply isolation and disinfection. while in Indonesia is the latest way to vaccinate the fish farming.Vaccination is one of the preventive measures in tackling diseases of fish. The use of drugs and chemicals for the treatment of fish are becoming obsolete. This is due to negative impacts such as environmental pollution, residues in the fish's body, and bacterial resistance to certain types of antibiotics. There are several types of vaccines have been developed for the prevention of disease furunculosis among other carp, coho salmon, rainbow trout. vaccination of fish is used to prevent disease caused by a virus not only but also bacteria such as Aeromonas and vibrio.
vaccines generally empirically developed from an attenuated virus or bacteria. whereas how to use it the way the fish submerged in the liquid (immersion vaccine), by injection into the body of the fish, with fish food (included in artificial food and natural food / oral vaccine).
There are advantages and disadvantages of each method. Vaccines are submerged into the water so the fish are not as effective in the absorption into the mouth, the more fluid that does not fit into the digestive organs. Similarly, the method through food, vaccines become damaged while in the intestines of fish. then the method developed by adding oral biofilms in food wrapping fish vaccinated (vaccine commercial food products), while the vaccine by injection is more effective because it is directly injected intra-peritoneal. But in practice, the vaccine injection more troublesome in application because more fish then more effort and time in doing so, so the cost of production is also increased, while the immersion vaccine easy and rapid time to do it.
There are several things to consider in order to run an effective vaccine is the temperature, stress caused by environmental or man-made factors such as changes in photoperiod, salinity, heavy metals, overcrowding, handling and transport will hamper the efficacy of the vaccine during the vaccination process .because the purpose of the vaccine is to get the memory of the fish's body, so the body's auto immune fish will work when there are bacteria or viruses that attack, so the fish should be in a state of good health when vaccinated
Aquaculture Fisheries Development