fish viruses microbiology
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VIRUSES
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Are Viruses Living orAre Viruses Living or
NonNon--living?living? Viruses are both and neither
They have some properties of lifebut not others For example, viruses can be killed,
even crystallized like table salt
However, they cant maintain aconstant internal state(homeostasis).
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What a Virus Isnt
Not a bacterium...
Not independent... Cannot survive in absence of a living cell
within which to replicate...
Antibiotics generally dont work on them...
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Whatare Viruses?Whatare Viruses?
A virus is a non-
cellular particle madeup of genetic materialand protein that can
invade living cells.
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What Viruses Are...
Infectious agents composed mainly of nucleic acid
with a protein coat (capsid)
Visible with electron microscope (10-200 nM)
Carry on normal cell-like function (unless free, then
infectious)
In infectious form: no growth; no respiration??? Can enter living plant, animal or bacterial cell
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Discovery of VirusesDiscovery of VirusesBeijerinck (1897)coined the Latin namevirus meaning poison
He studied filteredplant juices & foundthey caused healthyplants to become sick
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Tobacco Mosaic VirusTobacco Mosaic Virus
Wendell Stanley(1935) crystallized
sap from sicktobacco plants
He discovered
viruses were made ofnucleic acid andprotein
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SmallpoxSmallpox
Edward Jenner (1796)developed a smallpoxvaccine using milder
cowpox virusesDeadly viruses aresaid to be virulent
Smallpox has beeneradicated in theworld today
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Viewing VirusesViewing Viruses
Viruses areViruses are smallersmallerthan the smallest cellthan the smallest cell
Measured inMeasured in
nanometersnanometersViruses couldnt beViruses couldnt beseen until theseen until the electronelectronmicroscopemicroscope waswasinvented in theinvented in the 2020thth
centurycentury
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Electron Microscopy
Mitra, K. & Frank, J., 2006. Ribosome dynamics: insights from atomic structure modeling into cryo-electron
microscopy maps.Annual review of biophysics and biomolecular structure, 35, 299-317.
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X-ray Crysta
llography of Viruses
Symmetry of protein shells makes them uniquely
well-suited to crystallographic methods
Viruses are the largest assemblies of biological
macromolecules whose structures have been
determined at high resolution
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ViralViralStructureStructure
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Virus Appearence? 1. Capsid
2. Core and genetic material (DNA/RNA)
Capsid: outer shell of the virus which encloses genetic material
(link: chemical structure of capsid helps determine immune
response to virus)
capsid is made of many identical individual proteins
protein core under capsid protecting genetic material
sometimes an additional covering (lipid bilayer w/embedded
proteins) on outside known as an envelope ( like a baseball)
various forms: rods, filaments, spheres, cubes, crystals
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CharacteristicsCharacteristics
Non living structures
Noncellular
Contain a protein coat called thecapsid
Have a nucleic acid core containing
DNA or RNA Capable of reproducing only when
inside a HOST cell
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CharacteristicsCharacteristics
Some viruses areenclosed in anprotective envelope
Some viruses may havespikes to help attach tothe host cell
Most viruses infectonly SPECIFIC hostcells
CAPSID
ENVELOPE
DNA
SPIKES
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CharacteristicsCharacteristics
Viral capsids(coats) are madeof individualprotein subunits
Individual
subunits arecalled capsomeres CAPSOMERES
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Capsid
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capsomere: unit/molecule associated with capsid structure
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CharacteristicsCharacteristics
Outside of host cells,viruses are inactive
Lack ribosomes and
enzymes needed formetabolism
Use the raw materials
and enzymes of the hostcell to be able toreproduce
EBOLAVIRUS
HIVVIRUS
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Size of VirusesSize of Viruses
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Viral ShapesViral Shapes
Viruses come in a variety ofshapes
Some may be helical shape likethe Ebola virus
Some may be polyhedral
shapes like the influenza virusOthers have more complex
shapes like bacteriophages
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T
ypical
Virus Shapes
RODS SPHERES
CUBES
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The Structure of Viruses
Tobacco
Mosaic
Virus
HIV
Bacteriophage
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Helical VirusesHelical Viruses
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Polyhedral VirusesPolyhedral Viruses
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More Virus Shapes
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Complex VirusesComplex Viruses
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Taxonomy ofTaxonomy of
VirusesViruses
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ira Taxonomyira TaxonomyExamplesExamples
Herpesviridae
Herpesvirus
Human herpes virus 1, HHV 2, HHV 3
Retroviridae
Lentivirus Human Immunodeficiency Virus 1, HIV 2
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Herpes VirusHerpes Virus
SIMPLEXI and II
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AdenovirusAdenovirus
COMMONCOLD
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Influenza VirusInfluenza Virus
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PapillomavirusPapillomavirus Warts!Warts!
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RNA or DNA Virus
Do or do NOT have an envelope
Capsid shape
HOST they infect
Used for VirusUsed for Virus
IdentificationIdentification
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Bacteriophages
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PhagesPhages
Viruses that attackbacteria are calledbacteriophage or just
phageT-phages are aspecific class of
bacteriophages withicosahedral heads,double-stranded DNA,and tails
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TT--phagesphages
The most commonly studiedT-phages are T4 and T7They infect E. coli , an
intestinal bacteriaSix small spikes at the baseof a contractile tail are usedto attach to the host cellInject viral DNA into cell
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EscherichiaColi
Bacterium
T - EVENPHAGESATTACKTHISBACTERIUM
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E. Coli and the
Bacteriophage
What it looks like in real
life
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T-Even Bacteriophages
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Diagram of TDiagram of T--44BacteriophageBacteriophage
Head with 20triangular
surfacesCapsidcontains DNA
Head & tailfibers madeof protein
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Composition ofT-Even
Bacteriophage
Capsid: brains of virus,
tightly-wound protein
protecting nucleic acids Body: attached to
capsid head, rod-like
structure w/retractible
sheath, hollow core
Tail: at end of core is a
spiked plate carrying 6
slender tail fibers,
anchor virus to its host
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R
et
rovirusesR
et
roviruses
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Characteristics of RetrovirusesCharacteristics of Retroviruses
Contain RNA, not DNA
Family Retroviridae
Contain enzyme called ReverseTranscriptase
When a retrovirus infects a cell,
it injects its RNA and reversetranscriptase enzyme into thecytoplasm of that cell
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Change DNA
into RNA.
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ENZYME
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RetrovirusesRetroviruses
The enzyme reversetranscriptase (orRTase), which causessynthesis of acomplementary DNAmolecule (cDNA) using
virus RNA as atemplate
RTase
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RetrovirusesRetroviruses
HIV, the AIDSvirus, is a retrovirus
Feline LeukemiaVirus is also aretrovirus
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Viroids & PrionsViroids & Prions
dd
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ViroidsViroids
Small, circular RNAmolecules without aprotein coat
Infect plantsPotato famine inIreland
Resemble intronscut out ofeukaryotic
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PrionsPrionsPrions are infectiousproteins They are normal bodyproteins that getconverted into an alternateconfiguration by contactwith other prion proteins They have no DNA orRNA
The main protein involvedin human and mammalianprion diseases is calledPrP
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Prion DiseasesPrion Diseases
Prions formPrions form insolubleinsolubledeposits in the braindeposits in the brainCauses neurons toCauses neurons torapidly degeneration.rapidly degeneration.
Mad cow diseaseMad cow disease (bovine(bovinespongiform encephalitis:spongiform encephalitis:BSE) is an exampleBSE) is an examplePeople in New GuineaPeople in New Guinea
used to suffer fromused to suffer fromkurukuru, which they got, which they gotfrom eating the brainsfrom eating the brainsof their enemiesof their enemies
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Viral ReplicationViral Replication
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How do viruses work?
Viruses make use of the host cells chemical energy,
protein and nucleic acid synthesizing ability to replicate
themselves...
each virus attacks a specific type of cell cold viruses attack cells of the lung
the AIDS virus attacks T4 cells of the
immune system
fish viruses are just as specific
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Bottom Line...
All viruses only exist to make more viruses
Most are harmful
Replication = host cell death.
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VirusalMechanism
Viruses contain single- or double- stranded DNA
or RNA
Often, the virus alters the intracellularenvironment enough to damage or kill the cell
(oops!!)
If enough cells are destroyed, disease results!
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Role ofRNA/DNARole ofRNA/DNA Supplies the codes for building the protein coat
(capsid) and for producing enzymes needed toreplicate more viruses
Information given so newly-built viruses can lyse cells(e.g., bacteriophage)
Result: cell destroyed.
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Viral AttackViral Attack
Viruses are very specific as towhich species they attack
HOST specific Humans rarely share viral diseases
with other animals
Eukaryotic viruses usually haveprotective envelopes made fromthe host cell membrane
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5Steps of Lytic Cycle5Steps of Lytic Cycle
1. Attachment to the cell 2. Penetration (injection) of viral DNA or
RNA
3. Replication (Biosynthesis) of new viralproteins and nucleic acids 4. Assembly (Maturation) of the new
viruses
5. Release of the new viruses into theenvironment (cell lyses) : DNA incorporated(10 minutes) hundreds of virions appear causingthe cell to rupture, releasing hundreds of small
viral replicates
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Bacteriophage ReplicationBacteriophage Replication
Bacteriophageinject theirnucleic acidThey lyse (breakopen) the
bacterial cellwhen replicationis finished
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Bacteriophage Attack
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Attachment Phage attaches by tail fibers tohost cell
Penetration Phage lysozyme opens cell wall,
tail sheath contracts toforce tail core and DNA intocell
Biosynthesis Production of phage DNA
and proteins Maturation Assembly of phage particles
Release Phage lysozyme breaks cell wall
Lytic Cycle ReviewLytic Cycle Review
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Common steps in the assembly of alldsDNA viruses
Unique portal ring at one Vertex
Scaffolding proteins
Procapsid assembled empty of DNA
DNA pumped into procapsid through portal ring
DNA moves back through portal to enter cell
Pathway
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Attachment:Phage attachesto host cell.
Penetration:Phage pnetrates hostcell and injects itsDNA.
Merozoites releasedinto bloodsteam fromliver may infect newred blood cells
1
2
3
Bacterialcell wall
Bacterialchromosome
Capsid DNA
Capsid
Sheath
Tail fiber
Base plate
Pin
Cell wall
Tail
Plasma membrane
Sheath contracted
Tail core
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4 Maturation:Viral components areassembled into virions.
Tail
5 Release:Host cell lyses andnew virions arereleased.
DNA
Capsid
Tail fibers
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OneOne--step GrowthCurvestep GrowthCurve
V l LV l L
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Viral LatencyViral Latency
Some viruses have the ability tobecome dormant inside the cellCalled latent viruses
They may remain inactive for longperiods of time (years)Later, they activate to produce new
viruses in response to some externalsignalHIV and Herpes viruses are
examples
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Lysogenic CycleLysogenic Cycle
Phage DNA injected into host cellViral DNA joins host DNA forming aprophageWhen an activation signal occurs,the phage DNA starts replicating
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Lysogenic CycleLysogenic Cycle
Viral DNA (part of prophage) may stayinactive in host cell for long periods oftime
Replicated during each binary fission
Over time, many cells form containingthe prophages
Viral LatencyViral Latency
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Viral LatencyViral LatencyOnce a prophage cell is activated, host cell enters the
lytic cellNew viruses form a & the cell lyses (bursts)Virus said to be virulent (deadly)
INACTIVESTAGEACTIVE
STAGE
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Virulent VirusesVirulent Viruses
HOST
CELL
LYSES &
DIES
The Lysogenic CycleThe Lysogenic Cycle
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The Lysogenic CycleThe Lysogenic Cycle
L t n in E k tL t n in E k t
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Latency in EukaryotesLatency in EukaryotesSome eukaryotic virusesremain dormant for manyyears in the nervoussystem tissues Chickenpox (caused bythe virus Varicellazoster) is a childhoodinfectionIt can reappear later inlife as shingles, a painfulitching rash limited tosmall areas of the body
SHINGLES
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Latency in EukaryotesLatency in Eukaryotes
Herpes viruses alsobecome latent in thenervous system
A herpes infection lastsfor a persons lifetime
Genital herpes (HerpesSimplex 2)
Cold sores or feverblisters (HerpesSimplex1)
SKINTOSKINCONTACT
PASSEDATBIRTHTO
BABY
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The Virus Invasion
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Whats Infected by a Virus?
All living things have some susceptibility to a
particular virus
Virus is specific for the organism Within a species, there may be a 100 or more
different viruses which can affect that species
alone
Specific: for example, a virus that only affects
one organism (humans and smallpox)
Influenza can infect humans and two animals
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DifferentTypes of Viruses
Major classifications: animal, plant, bacterial
Sub-classified by arrangement and type of nucleic
acid
Animal virus group: double-stranded DNA, single-stranded DNA, double-stranded RNA, single-
stranded RNA, retrovirus
Influenza: SS-RNA
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Do Viruses ever Change?
Mutations do occur.
If the mutation is harmful, the new virus particlemight no longer be functional (infectious)
However, because a given virus can generate many,many copies, a small number of non-functionalviruses is not important
Mutation is not necessarily damaging to the virus --
it can lead to a functional but new strain of virus
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VirulenceVirulence
VIRUS DESTROYING HOST CELL
Lytic and Lysogenic CyclesLytic and Lysogenic Cycles
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Lytic and Lysogenic CyclesLytic and Lysogenic Cycles
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Defense Against Viruses
First Line: skin and mucous membrane, whichalso lines the gastrointestinal and respiratorypassageways
skin is tough and stomach acidity acts as adisinfectant
Second Line: after the virus enters the blood andother tissues, white blood cells and related cells
(phagocytes) consume them accumulation of phagocytes in area of infection is
known as puss
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Defense Against Viruses
Antibodies are the best defense against viruses
unfortunately, they are specific in their action
chickenpox antibody will only attack a chickenpox virus a particular virus stimulates the production of a particular
antibody
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Defense Against Viral Infection
Animals are protected in several ways:
1)intracellular: if a particular virus attacks cells, our
bodies produce interferons
interferons (alpha, beta or gamma) are proteins which
interact with adjacent cells and cause them to become more
resistant to infection by the virus
if the resistance is not quite good enough, we become sick
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Defense Against Viral Infection
2)immune system (extracellular): kills the virusoutside the cell
also kills the infected cells
virus cannot spread
eventually the virus is completely removed and weget better
exception: HIV because it infects cells of theimmune system, itself
chemicals/drugs: acyclovir, AZT, HIV proteaseinhibitor, several fish vaccines available.
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Major Fish Viruses
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Major Viral Infections in Fish
Infectious pancreatic necrosis (IPN)
Viral hemorrhagic septicemia (VHS)
Infectious hematopoetic necrosis (IHN)
Channel catfish virus disease (CCVD)
(1) I f i P i N i
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(1)Infectious Pancreatic Necrosis
(IPN)
What?: viral infection of salmonids (trout and char)
Time: Acute
Result: high mortality (fry and fingerlings)
Rare in larger fish (good thing!)
History: Isolated in Pacific NW in 1960s, wiped out brook
trout in Oregon in 1971-73
Size: Only 65 nM in diam., smallest of fish viruses
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IPN: generalnotes
Single capsid shell, icosohedral symmetry, no envelope
Contains two segments of DS-RNA
Fairly stable and resistant to chemicals (acid, ether, etc.),
variable resistance to freezing
Remains infectious for 3 months in water (uh oh!)
Targets pancreas and hematopoietic tissues of kidney and spleen
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IPN: epizootiology (disease process)
Who?: All salmonids, brook trout most susceptible,
marine fish (flounder?)
Reservoirs (where)?: carriers, once a carrier always a
carrier, virus particles shed in feces/urine Transmission (how?): horizontal, by waters via
carriers or infected fry; vertical from adults to
progeny; experimentally by feeding infected material,
IP injection
Pathogenesis: entry via gills, digestive tract
Environmental factors: mortality reduced at lower
temps (why?); however, carriers not reduced
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IPN: pathology (what do we see?)
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IPN: detection, diagnosis and control
Isolation: whole fry, kidney, spleen, pyloric cecae, sexfluids are all good sources, .i.e. check these!!!
Presumptive tests: epizootiological evidence and/or typical
PCR in infected cells
Definitive tests: serology
(fluorescent antibody test (FAT))
Control: avoid virus in water, virus-free
stock, destruction of infected stock,
vaccine exists now!
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Other species known to be
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Other species known to be
susceptible
amago salmon (Oncorhynchus rhodurus)Arctic char (Salvelinus alpinus)Atlantic menhadden (Brevoortia tyrannus)carangids (Carangidae)chinook salmon (Oncorhynchus tshawytscha)chum salmon (Oncorhynchus keta)cichlids (Cichlidae)coho salmon (Oncorhynchus kisutch)common scallop (Pecten maximus)
cutthroat trout (Salmo c
larki)cyprinids (Cyprinidae)
Danube salmon (Salmo hucho)drums/croakers (Sciaenidae)eels (Anguilla spp)grayling (Thymallus thymallus)
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More
halibut (Hippoglossus stenolepis) herrings/sardines (Clupidae)Jap. amberjack (Seriola quinqueradiata) lake trout (Salvelinus namaycush)lampreys (Petromyzontyidae) left-eye flounders (Bothidae)loach (Misgurnus anguillicaudatus) loaches (Cobitidae)masou salmon (Oncorhynchus masou) Pacific salmon (Oncorhynchus spp)perches (Percidae) pikes (Esocidae)silversides (Atherinidae) sockeye salmon (Oncorhynchus nerka)soles (Soleidae) Southwest European nase (C. toxostoma)
striped snakehead (Channa striatus) suckers (Cotostomidae)
summer flounder (Paralichthys dentatus) turbot (Psetta maxima)white seabass (Moronidae) whitefish (Coregonidae)carp (Cyprinus carpio) goldfish (Carassius auratus)redfin perch (Perca fluviatilis) southern flounder (P. lethostigma)yellowfin bream (Acanthopagrus australis)
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Asymptomatic carriers...
coalfish (Pollachius virens)common carp (Cyprinus carpio)discus fish (Symphysodon discus)goldfish (Carrasius auratus)heron (Ardea cinerea)loach (Cobitidae)minnow (Phoxinus phoxinus)noble crayfish (Astacus astacus)pike (Esoxlucius)
river lamprey (Lampetra fluviata
lis)shore crab (Carcinus maenas)
Spanish barbel (Barbus graellsi)white suckers (Catostomas commersoni)
Infectious pancreatic necrosis in Atlantic salmon.
Note swollen stomach and 'pop eye'
Source: Australian Animal Health Laboratory
...what now???
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(2) ViralHemorrhagic Septicemia (VHS)
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(2)ViralHemorrhagic Septicemia (VHS)
What?: Viral disease of European salmonids
When?: Recognized in Denmark in 1949, isolated
from Pacific Coast in 1989 Size: rhabdovirus, bullet-shaped (one rounded
end), 185 x 65 nM, lipoprotein envelope
non-segmented SS-RNA
Constitution: sensitive to ether and chloroform,heat, acid, resistant to freeze-drying
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ViralHemorrhagic Septicemia (VHS)
Pathogenesis: infection results in viremia, disrupts many
organ systems, 200-300g fish most affected
Environmental factors: low temp (< 8oC, 46oF)
External pathology: lethargy, hanging downward in water
(dropsy), swimming in circles, exopthalmia, dark
discoloration, hemorrhages in roof of mouth, pale gillsw/focal hemorrhages
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ViralHemorrhagic Septicemia (VHS)
Internal pathology: gut devoid of food, liver pale,
hemorrhages in connective tissue, kidney gray and swollen
(chronic), red and thin (acute)
Histopathology: necrosis of liver, kidney nephrons,
spleen, pancreas, melanin in kidneys and spleen (OUCH!)
Isolation/tests: isolated from kidney/spleen,epizootiological evidence, definitive test is serum
neutralization, or FAT.
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ViralHemorrhagic Septicemia (VHS)
External hemorrhages
Liver red in acute stage
Viral haemorrhagic septicaemia in rainbow trout
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Viral haemorrhagic septicaemia in rainbow trout.
Note swollen stomach and pop eye
Viral haemorrhagic septicaemia in rainbow trout.
Note pale color of stomach region, pinpoint
haemorrhages in fatty tissue, and pale gills
Source:THstein
Type Prevalent host type and location
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Type Prevalent host type and location
I-aFarmed rainbow trout and a few other freshwater fish in continental
Europe[10]
I-bMarine fish of the Baltic Sea, Skagerrak, Kattegat,North Sea,
Japan[1]
I-c Farmed rainbow trout Denmark
I-d Farmed rainbow trout inNorway, Finland, Gulf of Bothnia
I-e Rainbow trout in Georgia, farmed and wild turbot in the Black Sea[11]
II Marine fish of the Baltic Sea
III
Marine fish of the British Isles and northern France, farmed turbot in
the UK and Ireland, and Greenland halibut (Reinhardtius
hippoglossoides) in Greenland[12]
IV-aMarine fish of the Northwest Pacific (North America), North
American north Atlantic coast,[13] Japan, and Korea[1][14]
IV-b Freshwater fish in North American Great Lakes region[14]
Virus presence spread through much of the Great Lakes from 2003-2007.
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ViralHemorrhagic Septicemia
Prevention: clean broodstock and water = clean fish, avoid
infected broodstock, test and slaughter
Can spread very quickly from farm to farm: avoid close
proximity to other farms
Vaccines are under development.
One EPA-approved disinfectant: Virkon AQUATIC
(made by Dupont). Bleach kills the VHS virus.
(3 ) Infectious Hematopoietic Necrosis
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(3)Infectious Hematopoietic Necrosis
(IHN)
Who: sockeye, chinook, rainbows; cohos resistant
When?: 1950s in Oregon hatcheries. 100 million
mortalities between 1970-1980, if infected, 70%
mortality likely, esp. in young fish (fry: 90-95%
mort. possible)
What?: bullet shaped rhabdovirus, non- segmented
SS-RNA, sensitive to heat and pH, glycoprotein is
spiked on surface of virus
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Infectious Hematopoietic Necrosis (IHN)
Reservoirs: survivors life-long carriers, adults shed virusat spawning
Transmission: horizontal, primary mode is vertical viaovarian fluid (virus hitches ride on sperm into egg);
however, feces, urine, and external mucus possible. Also,
feeding and inoculation have worked experimentally
Pathogenesis: gills suspected; incubation period dependson temp, route, dose, age; extensive hemorrhaging,necrosis of many tissues; death usually due to kidneyfailure
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Infectious Hematopoietic Necrosis (IHN)
Environmental factors: temp. very important,
slows below 10C, holding in tanks/handling
increase severity (doesnt occur naturally >15 C)
External pathology: lethargy, whirling, dropsy,exopthalmia, anemia, hemorrhaging of
musculature/fins, scoliosis
Internal pathology: liver, kidney, spleen pale;
stomach/intestines filled with milky fluid;petechial hemorrhaging
Histopathology: extensive necrosis of
hematopoetic tissue of kidney/spleen
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Infectious Hematopoietic Necrosis (IHN)
Definitive diagnosis: serum neutralization, FAT, ELISA
Prevention: avoidance, quarantine, clean water with UV,ozone, virus-free stock; test, slaughter, disinfect; disinfect
eggs; vaccines under development; elevated water temp
No vaccines as of June 2007.
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(4)ChannelCatfish Virus Disease (CCVD)
Contagious herpes virus affecting only channel catfish less
than four months old
Occurs in SE United States, California, Honduras
Acute hemorrhagia, high mortality, discovered in 1968
Agent: enveloped capsid, icosohedral nucleocapsid with162 capsomeres
Physio/chemical properties: easy to kill, sensitive to
freeze-thaw, acid, ether, etc.
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ChannelCatfish Virus Disease (CCVD)
Environmental factors: optimal temperature 28-30C,
common during warmer months, cooler water = big
difference
epizootiology: horizontal, vertical suspected
external pathology: spiral swimming; float with head at
surface; hemorrhagic fins, abdomen; ascites; pale or
hemorrhagic gills; exophthalmia
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ChannelCatfish Virus Disease (CCVD)
Internal pathology: hemorrhages of liver, kidney,
spleen, gut, musculature; congestion of
mesenteries and adipose
Histopathology: necrosis of kidney, other organs;macrophages in sinusoids of liver, etc.;
degeneration of brain
Presumptive diagnosis: clinical signs,
epizootiological evidence
Definitive diagnosis: SN or FAT.
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ChannelCatfish Virus Disease (CCVD)
Prevention: avoid potential carriers (survivors) or infected
fry, keep temperature below 27oC (will still produce
carriers), attenuated vaccine shows some promise
Therapy: none available...
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ChannelCatfish Virus Disease
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ChannelCatfish Virus Disease
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However, you can always take precautions!
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UY - 2011
Treatment for ViralTreatment for ViralDise
ase
Dise
ase
VaccinesVaccines
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UY - 2011
VaccinesVaccines
An attenuated virus is a weakened, lessvigorous virus
Attenuate" refers to procedures that
weaken an agent of disease (heating) A vaccine against a viral disease can bemade from an attenuated, less virulentstrain of the virus
Attenuated virus is capable of stimulatingan immune response and creating immunity,but not causing illness
Perbandingan beberapa tipe vaksin ikan
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UY - 2011
IHNV, VHSV,
HIRRV, IHV-
1
Terbatas pada protein
immunogensTanpa resiko infeksi;Mudah
dikembangkan & produksi;
Vaksin Stabil; Menginduksi
respon imun cellular &
humoral
DNA vaccineDNA vaccineGenerasiGenerasi
IIIIII
IHNV, VHSV,
SVCV
Sulit dalam purifikasi
(biaya produksi tinggi)
Tidak mengaktifkan imun
respon seluler
Tidak mahal,
Memungkinkan
produksi skala besar
RecombinantRecombinant
proteinprotein
vaccinevaccine
GenerasiGenerasi
IIII
IPNV, IHNV,
VHSV, CCVMahal, Potensi resiko
terinfeksi
Imunitas jangka
panjang,M
enginduksirespon imun cellular
dan humoral
LiveLive
attenuatedattenuatedvaccinevaccine
VHSV, RSIV,
GCHV, ISAV,
IPNV, IHNV,
SVCV, CCV
Mahal,Kasus perkasus
tdk ada efeknya,
Imunitas jangka pendek
-> perlu injeksi booster
Resiko infeksi (-)
InactivatedInactivated
vaccinevaccine
GGenerasienerasi II
JenisVirusKekuranganKelebihanJenisVaksin
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