Term
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Definition
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Term
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Definition
| mouse mammary tumor virus, 8opvine pulmonary adenomatosis virus |
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Term
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Definition
| FeLV, FeSV, Murine leukemia virus, human leukemia virus |
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Term
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Definition
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Term
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Definition
| dermal sarcomas and hyperplasia (Walleyes) |
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Term
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Definition
| HIV, FIV, SIV, EIA, CAEV (Visna (CNS)/maedi (lungs) virus; "maedi" = "slow") |
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Term
| Retroviridae: simple (ie. gag, pol, env genes) v. complex genome )gag, pol env, AND genes coding for regulatory proteins) |
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Definition
Simple - alpha, beta, gammatretroviruses
Complex - delta, epsilon, lentiretrociruses |
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Term
T/F Retroviruses cause latent infections
T/F Retorviruses are very labile outside of the host |
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Definition
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Term
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Definition
REVERSE TRANSCRIPTION w/in cytoplasm! -> enters nucleus & is now a "PROVIRUS" (ie. integrated dsDNA)
Some:
splice generating GAG-pol precursor (ie. structural genes = RT, Integrase)
Some -(read thru gag-pol)-> long polypeptide, cleaved -> RT & IT incorporated into virus (~1:20)
Some translation: move thru vesicles (Golgi, ER, CM) incorporated
Packaging
Egression |
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Term
| requirements for international movement of dogs |
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Definition
proof of vaxx, VN test: RFFIT (Frapid flourescent focus inhibition test), FAVN (flouresecent Ab virus neuralizatoin test)
Microchip ID
Quarantine (1-6 mos) |
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Term
| Simple v. Complex proviruses & antiviral targets & *excpetions |
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Definition
Simple- contains Pr (protease) = ANTIVIRAL TARGET
Gag-strucutral proteins (c0re)
pol = RT IN + Pr (enzymes)
envelope SU, TM
LTR = enhancers, promoters
LENTIVIRUS = lots of genes encoding for small regulatory proteins = ANTIVIRAL therapy |
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Term
| Functions of some lentivurs regulatory proteins |
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Definition
vif: binds to and degrates APOBEC 3G protein (which is a part of intrinsic defense- incorporates into proten virions and interfese w subsequent relication
tat: transactivation of virus gene (tax- homologous gene of BoLV)
rev: export of viral RNA from nucleus
nef: down regulates CD4 recepotrs |
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Term
| replication of competent vs. incompetent retroviruses |
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Definition
replication competant viruses = EXOGENOUS (can leave host) and are transmitted HORIZONTALLY (ie. FeLV, ALV, BoLV)
NOTE: ALV is passed VERTICALLY: congenital (chronic, leukemia) or provirus = genetic (latent, sometimes leukemia)
ENDOGENOUS (remains as provirus w/in host DNA) and transmitted GENETICALLY
these can be "rescued" by replicaiton competent viruses ie. exogenous FeLV/ednogenous FeLV (results in genetic changes of exogenous FeLV (ie. different subgroups) (ie. FeSV some FeLVs) |
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Term
| Mechanisms of retrovirus oncogenesis: Insertional mutagenesis |
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Definition
Insertional mutagenesis/cis-activation - cell oncogenes come under control f provirus LTR w its strong enhancer and promoter elements ie. cis-activation
specific c-oncs can be disrupted by insertion of provurs, a random process ie. insertional mutagenesis - ie. responsible for the VARIABLE/RANDOM incubation time of FeLV in infected cats |
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Term
| Mechanisms of Retrovirus replication (3) |
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Definition
insertional mutagenesis
transduction
transactivation |
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Term
| Mechanisms of retrovirus replication: Transduction |
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Definition
Transduction - acquisition of a virus oncogene (v-onc) ie. a portion of a c-onc w/o its control elements:
conc products (oncoproteins) regulate cell activities including mitosis (c-oncoprotein production is controlled by a feed back mechansism; v-onc's cannot be regulated ie. NO feedback mechanism b/c they represent c-onc's w/o control elements)
essentially all retroviruses have the ability to acquire host DNA iee. oncogenes or other DNA (xenotropic retroviruses have the potential to transfer genetic elements w/in and btw species
Rous sarcoma virus is a classical example of a retrovirus that has acquired a v-onc: ACUTELY transforming retroviruses (v-onc expressed immediately once in host cell)
"Read through" + normal c-onc -> intramolecular recombination -> v-onc |
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Term
| Mechanisms of retrovirus replication: Transduction |
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Definition
| retroviruses encoded regulatory proteins that can affect cell growth activities ie. the transactivating genes TAX of BoLV & TAT of HIV |
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Term
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Definition
subgroups: A,B,C,T - based on env gene & receptor specificity (aka "receptor usage")
FeLV-A represented in host w/ or w/o FeLV-B,C (subgroups FeLV-B & C arise de novo from recombination of env gene w/ engeogeous FeLVA (B &C responsible for CLINCIAL MANIFESTATIONS)
FeLV-B & C replication in hu cell cultures w/ no evidence of human infection (A DoES NOT REPLICATE in hu cell cultures)
ontogeny:
day 0 = FeLV-A infection
Primary viremia: Targets lnn, spleen, IT UB, Salivary gl, bone marrow
Day 7-14: Seoncdary Viremia
Shedding
**Immune response may terminate infection (<16 wks) o r= PI if >16 wks(mos - yrs?) |
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Term
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Definition
Lymphosarc: multicentric, thymic, alimentary, invasive Tcell tumors in non-lymphoid tissue (CNS, skin, eye)
Myeloproliferative dz & anemia: : erytheatic myelosis (erythroid progenitor cells), granulocytic leukeia (myeloid progenitor cells)
Immuno-pathogenic dz: immune complex(ie. GN (rare)), immuno suppressin:(decr in T cells (CD4, CD8) B cells & myeloid cells - enhancement of FIP herpes crypto, Mycoplasma infections; slow wound healing, gingivitis, chronic respiratory dz, etc)
Fibrosarc: (rare) multifocal s.c. in young kittens, induced by FeSV but requires FeLV-A as helper |
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Term
| Why so many FeLV dz manifestations? |
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Definition
FeLV-A strains assoc w marked immune suppression: have specific env mutation
intramolecular recombination of FeLV-A w endogenous FeLV-A & other retrovirus elements in host DNA + mutation generate: FeLV-B assoc w THYMIC LYMPHOSARC & FeLV-C assoc w SEVERE APLASTIC ANEMIA
Determinants of virulence/dz manifestation:
1. site of provirus insertion -> disregulationof specific c-onc genes (6 loci) - ie. thymic vs.alimentary lymphosarc
2. Mutations in env/SU -> utilization of different receptors
3. LTR variability btw isolates |
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Term
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Definition
1. Ag capture ELISA: positive test mayor maynot mean PI but likely if positive >16 wks
2. Direct FA detects AG associated w/ neutrophils and plts in unfixed blood semars - positive test indicates probable PI as it generally becomes positive ~3 wks after initial infection
3. RT-PCR (tests viral nucleic acid, RT) |
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Term
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Definition
Killed
*Canarypox recombinant -> SU = VAXX TARGET (=Anti-R & keeps virus from getting into cell) - serogroups are determined by specificity to SU glycoprotein |
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Term
| FeSV model: Rescue by FeLV |
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Definition
1. cel w replication imcompetent FeSV
2. co-infection w/ FeLV that contains genes for replication
3. progeny FeLV & FeSV released. FeSV free to infect susceptible cell. v-onc expressed if provirus inserts into ACTIVE area
(FeSV acquires envelope of FeLV - required for replication) |
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Term
| challenges of antiviral drugs |
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Definition
1. timing (viruses typically have done significant damage before their presence is recognized) - countered by rapid dx & prophylacti antiviral drugs
2. Drug-resistant mutants arise quickly (minimized by use of drug combos ie. HIV)
3. Safety -viruses are obligate parasites and use many o the same physiological pathways of the cell, thus toxicity is an issue (ID ts in virus replication cycle that are unique to the virus whenever possible ie. vRNA dRNApol, cap snatching, etc) |
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Term
| Nucleoside analogs: Herpesviruses |
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Definition
IDU (5'-iodo-2'-deoxyuridine) - topical tx of herpetic corneal ulcerts today derivatives of acyclovir are more commonly used (topical: cidofovir, systemic: famciclovir)
2. Ara-a (adenine arabinoside) - first parenteral effective against HSV VSV
3. Acyclovir: chain terminator
1. inhibits vDdD (significalntly higher 2. affinity for vDdD than cDdD)
a "prodrug" that is activated by herpesvirus **thymidine kinase in virus infected cells
The Beta-herpesvirinae ie. cytomegalo viruses do NOT encode viral th kinase but have kinases capable of phosphorylating the acyclovir derivative, gancyclovir
(Acyclovir -(th kinase)> Acyclovir monophosphate -(cellular kinase enzymes)> acyclovir triphosphate -(viral polymerase)> incorporated into replicating vDNA (& cDNA)) -> CHAIN TERMINATION
relatively poor bioavailability therefore most useful for topical tx; Valtrex "prodrug" used sysntemically (valine enhances uptake from gut) |
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Term
| Nucleoside derivatives: Acycloviru |
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Definition
3. Acyclovir: chain terminator
1. inhibits vDdD (significalntly higher 2. affinity for vDdD than cDdD)
a "prodrug" that is activated by herpesvirus **thymidine kinase in virus infected cells
The Beta-herpesvirinae ie. cytomegalo viruses do NOT encode viral th kinase but have kinases capable of phosphorylating the acyclovir derivative, gancyclovir
(Acyclovir -(th kinase)> Acyclovir monophosphate -(cellular kinase enzymes)> acyclovir triphosphate -(viral polymerase)> incorporated into replicating vDNA (& cDNA)) -> CHAIN TERMINATION
relatively poor bioavailability therefore most useful for topical tx; Valtrex "prodrug" used sysntemically (valine enhances uptake from gut) |
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Term
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Definition
Amantadine:
mode of action: UNCOATING
low dose affects M2 ion channel and only affective against Type A influenza
high dose acts as a high base (increases pH w/in endosome interfeering w/ pH-dependent membrane fusion, effective against type A which has M2 channel, types B & C IV that do Nnot
*also inferferes w/ maturation of HA as it is processed in cell secretory pathway
Resistant mutants arise quickly
CNS side effects (crosses BBB!)
Methylated derivative aka Rimantadine does NOT cross the BBB
Amantadine also used to alleviate symptoms of Parkinson's |
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Term
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Definition
NA interacts w/ SA residues on cell surface & prevents progeny virus from "pilling up" on CM during release
enzyme active sites of NA are highly conserved, thus virus mutants occur less requently than amantadine-induced mutants
NA inhibition via:
Zanamivir (ihalation)
Oseltamivir (oral)
mode: derivatives of SA w/ greater affinity for the NA enzyme active site than SA |
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Term
| Picornavirus: antiviral drugs |
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Definition
Peconaril - onl for Enterovirus Encephalitits
blocks access to receptor bining site ni the floor of canyon
experimentally effective against Coxasackie & Thinoviruses |
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Term
| Retrovirus: antiviral drugs |
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Definition
attack RT (virus specific)
Proteases- chop Gag, pol etc = inhibit IT -> interferes w/ viral replication
HIV
LTR
all dependent on protease for production of RT & IN
Nucleoside analogs:
AZT for HIV: RT inhibitor/chain terminator (affinity of AZT for RT is ~100x > than dTTP; incorporated into viral DNA by reverse transcriptase
side effects common
multiple mutations in pol gene
Protease inhibitors:
Ritnovir, Sasquinavir, Indinavir, Nelfinavir (several)
mutations arise quickly
side effects are common : ritonavir, sasquinavir, have chymotrypsin-like effect on proteasome thus interfering w MHC-1 |
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Term
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Definition
LTR
all dependent on protease for production of RT & IN
Nucleoside derivatives: AZT:
RT inhibitor/chain terminator (affinity for AZT for RT is ~100x > than dTTP, incorporated into viral DNA by RT)
side effects common
multiple mutations in pol gene
Protease inhibitors:
Ritonavir, Sasquinavir, Indinavir, Nelfinavir (several)
mutations arise quickly
Side effects common: ritonavir, sasquinavir have chymotrypsin-like effect on proteasome thus interfering w/ MHC1
Integrase inhibitors:
Raltegaravir - Reverse transcribed product, vDNA cannot be integrated into host DNA |
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Term
| Other antiviral drugs: Cidofovir |
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Definition
Phosphorylated acyclic nucleoside anaglog
initial phosphorylation by viral tk not required*
phosphorlyation to triphosphate form completed by cell kinases
*broad spec for DNA & Retroviruses
topica, IV, oral |
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Term
| Other antiviral drugs: Ribavirin |
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Definition
nucleoside anaglog
interferes w/ "capping" of mRNA
decreases GTP pool in cell
interferes w/ RNAdRNApol
toxicity is a problem
used for Lassa Fever Hantavirus, Human RSV |
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Term
| Other antiviral drugs: INFs |
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Definition
use for Hepatitis C in humans
FIP, FIV, FeLV but efficacny not proven |
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Term
| Addressing the viral mutant issue |
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Definition
Drug coktails (ie. 2 (+) antivirals w/ differing targets
Atripla - combo of 1 nucleoside, 1 nuclotide, 1 non-nucleotide RT inhibitorSm |
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Term
| Small interfering (si) and micro (mi) RNAs |
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Definition
miRNAs in mammalian cells generated from RNA associated with specific genes in nucleus: used in post-transcriptional regulation
siRNAs are generated from viral RNA - interfere w/ host cell defense
si & miRNAs are ~13-20 nucleotides long linked to endonucleases (RISC) - si & miRNA-RISC (RNA induced silencing complex) bind & degrade target mRNA
Application of siRNAs: prevent and successfully treat RSV & PI3 using siRNA that target mRNA for a protein of the polymerase complex |
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Term
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Definition
NCD - Csartary LK - effective in lab experiments against malignant glioma in mouse model; effective in some human trials
Kills cancer via lysis and/or initiating apoptosis; effectiveness enhanced by inserting genes for IL2, NS1 and "highly fusogenic" F protein
ASENOVIRUSES - contitionally replicative ie. early genes removed (used for head & neck cancers glimoas others)
VSV - replication competent, effective in mouse model administered IV (glimoas & metastatic carcinoma in brain) |
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Term
| Oncolytic viruses w/ "pro-drugs" |
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Definition
Retrovirus model & work of K Culver in viral therapy for cancer
- developed a retrovirus vector (RV) arrying the HSV tk gene - establisha rat glimoa cell model, inject RV tumor at multiple sites, inactivate form of an acyclovir derivative, gancyclovir then administer IV: brain tumor eliminated or development suppressed
Requirements: plasmid containing retrovirus construct with GOI ie. HSV1 gene, tk
a packaging cell encoding all components of a replication competent retrovirus but w/o the packaging sequence
HSV - conditionally replicative w/ GOI (CYP2B1); virus kills cancer via:
1. Lysis &
2. activating a parenterally administered inactive form of cyclophosphamide by the CYP2B1 gene product (note: CYP2B1 prevents cell devision by cross-linking DNA strands) |
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Term
| Use of viruses in gene therapy |
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Definition
Viral vectors (DNA, RNA) can be used in tx of genetic disorders by introducing GOIs into target cells
Examples: Retro, adeno deno-associated viruses (dependovirus, parvoviridae), Herpes |
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Term
| considerations in choosing a gene for gene therapy |
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Definition
1. size of GOI & capacity of vector genome
2. target cells: susceptibility to infeciton, terminally differentiated or actively dividing?
3. can virus vector be engineered to carry out function with minial injury to host?: immune response ie. will host develop AB to vector, develop an exuberant inflammatory response?
4. Insertional mutagenesis and gene slicing |
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Term
| Retroviruses in gene therapy |
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Definition
effective vectors but require DIVIDING CELLS for max efficiency ie. not suitable for dzs such as cystic fibrosis;
Insertional mutagenesis & gene slicing are potential problems: Murine LV vector developed to tx SCID (servere combined immunodeficiency) in humans - tx successful but 4:10 principles developed leukemia due to insertional mutagenesis |
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Term
| Adenoviruses in gene therapy |
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Definition
ie. Cystic fibrosis
target = mucus secreting cells of Respiratory tract
adenovirus engineered to be replication incompetent and contain the human CFTR gene (ie. GOI)
GOI is episomal effects of txs are short-lived
Issues: Repearted txs raise neutralizing Ab to virus vector
immune response to viral protein can induce inflammation |
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Term
| AAV (Adeno-associated viruses) gene therapy |
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Definition
AAV being develop for variety of genetic disorders ie. Cystic Fibrosis Huntingtons Dz
GOI is primarily episomal but can integrate into cell DNA thus tx by AAV has the potential for a longer effect than tx adenoviruses
used not only to supply a normally functioning gene ie. "gene conditioning" but also to correct a defective gene "gene correction" ie. the "Holy Grail" of gene therapy
Issues: same as w/ adenoviruses but have advantage of being smaller virus (ie. less protein); insertional mutagenesis
AAV appear to integrate selectively at chromosome 19*
untington's dz: engineered AAV to: express Anti-receptor on capsid to target neurons expressing Huntingting protein (HP); generate miRNAs specific for mRNA of HP |
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Term
| Families of viruses that induce oncogenesis |
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Definition
Papilloma (carcinoma of hu genital tissue, transform by some bovine & rabbit viruses
Polyoma (SV40 ~Polio vaxx & risk of infection)
Adeno (some)
Hepadna (Hep B: Liver cancer)
Herpes : (EBV, Burkits lymphoma, MDV) |
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Term
| General characteristics of Papova & Polyomaviruses |
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Definition
small naked virions w/ icosahderal symmertry
genome is ds circular, only 1 strand is transcribed in Papilloma, both in Polyoma: papilloma do NOT replicate in cell culture
Papilloma: wart viruses: some app types transform cells, evlove to carcinomas ie. hu cervical carcinoma
Polyoma: Budgerigar Fledgiging dz: a generalized dz w/ high mortality, suspect "French molt" w/ feather defect also caused by this virus - affected fledgelings show weakness, pallor, s.c. hem, dehydrated, off feed, crop stasis (extended), death (30-80% mortality) - survivors shed virus in feces ~6 mos.
progressive multifocal leukoencephalopathy in immunosuppressed rhesus macaques (SV40) & humans (JC virus)
various solid turmos including SV40 in newborn rodents |
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Term
| replication of polyomavirus |
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Definition
| genome is too small to encode all proteins/enzymes that are required for replication - cell is induced by early gene products* of virus to prepare for mitosis which generates DdDpol and other compnents required for replication: early gene products "T" Ags of polyomaviruses & E5,6,7 gene products of papilloma interact w/ cell tumor suppressor proteins ie. pb53, Rb which have a role in regulating cell growth |
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Term
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Definition
binds w/ pb53/Rb
cell prepares to undergo division
cell produces:
1. DNA binding proteins
2. cell DdDpol
4. ribonucleotide reductase |
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Term
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Definition
binds w/ pb53/Rb
cell prepares to undergo division
cell produces:
1. DNA binding proteins
2. cell DdDpol
3. ribonucleotide reductase
When T reaches a critical level in the cytoplasm some T moves back into nucleus & binds to promoter region of its gene - production of mRNA specific for T is terminated
T also opens circular dsDNA which permists binding of cDdDpol to viral DNA and subsequent production of vDNA for progeny virions: simultaneously T facilitates expression of late genes that code for structural protein |
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Term
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Definition
| whole inactivated, replicating (wild, attenuated) |
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Term
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Definition
| subunit/split/viral like particles, molecularly altered live, vectored, chimeric, viral replicon particles DNA |
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Term
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Definition
| subunit/split/viral like particles, molecularly altered live, vectored, chimeric, viral replicon particles DNA |
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Term
| routes of administratino by virus |
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Definition
injection
eye drop - NCD
Aerosol - IBV
drinking water - IBV, NCD
Feed - NDV (regions where "cold chain" cannot be maintained
In ova - MD
Scarification - Orf, Fowl pox
Intranasal - Equine IV, BHV1, FIP |
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Term
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Definition
inactivated by formalin, gluteraldehyde, beta priopiolactone (rabies), ethylenemine (FMDV)
potential problems: failure to inactivate all virus, loss of immunogenicity
adjuvanated ie. aluminum hydroxide |
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Term
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Definition
wild type via unnatural route: SMALL POX: variolation, skin v aerosol
ORF (axilla), FOWLPOX (web wing) scarification
WIld type used in heterologous host:
COWPOX immunization of hu for SMALLPOX
TURKEY V for MAREKS
PIGEON POX for FOWLPOX by skin scarification
Attenuated viruses ie. MLV for CDV
naturally occuring attenuated ie. Bartha's K strain of PRV
serially passaged through unnatural host (cell culture, eggs, animals) |
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Term
| SUbunit/split vaxx, viruslike particles |
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Definition
Subunit (SU) or "split vaxx" contain 1(+) viral proteins but not all
the "DIVA" (differentiating infected from vaccinated animls) approach to dz control:
DIVA requires companion Dx tests for Ab to Ag NOT included in the vaxx
ie. an experimental vaxx developed for PRV (ISU) used envelop glycoproteins for SU vaxx and non-envelip proteins for Dx Ag
others: Hu IV split vaxx prepared by enzymatically cleaving HA from virus envelope
Virus Like Particles (VLP - recombinant self assemble into structural units forming capsids w/ nucleic acid
ie. hu genital papilloma virus vaxx
*Aleutian dz VLP - parvo virus - mink- recessive gene0defect in macrophages: affects ability fo macrophages to eliminate/destroy viral Ag/Ab complexes; virus retains infectivity; lots of Ab & Ag production -> GN |
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Term
| Expression systems used in producing vaxx Ag |
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Definition
Baculovirus: insect virus w/ a very powerful promoter/enhancer for the polyhedrin (PH) gene:
GOI cloned into PH gene
insect cells or Lepidoptera caterpillars infected w/ virus
Yeast: used in production of Hep B vaxx Ag
E. coli
Eukaryotic cells
Transgenic plants for oral vaxx Ag (ie. NOROVIRUS) |
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Term
| Molecularly altered live vaxx virus |
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Definition
deletion mutant/marker vaxx: 1(+) non-essential, highly antigenic viral proteins are deleted from vaxx candidate
ie. gE of BHV-1 vaxx, permits DIVA approach (ie. DIVA = IBR, PCV)
Temperature senstiive (ts) mutants ie. *"cold adapted": replication restricted to ~33oC URT
induce a balance immune response w/o causing systemic dz or repro losses
ie. IBR (aka BHV1), FIP |
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Term
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Definition
Vectored vaxx viruses are designed to infect a host w/o ill effect & carry a gene representing another virus to which immunity is desired
ie. VACCINA w/ Rabies G protein for immunizatino of wildlife population ie. raccoons
ie. CANARYPOX recombinat vaxx for: RELINE RABIES, FeLV, CDV, WNV
Construction of vectored vaxx:
1st virulence genes of the candidate virus vectorare ID's & neutralized/eliminated
GOI is cloned & inserted into a plasmid vector
ie. VACCINIA, CANARYPOX, ADENOVIRUS, HERPESVIRUS |
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Term
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Definition
two closely related viruses in which one serves as the backbone w/ replication associated genes and the other providing one(+) genes encoding protiens to which an immune response is desired
ie. Chimeri-Vax JE: backbone = YFV, immunogenic = JE
ie. PCV2 (PVC1 serves as a backbone) PCV2 contributes genes for capsids* |
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Term
| Virus Replicon Particles (VRP) |
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Definition
VRPs are replication defective viral particles that contain 1(+) GOIs
vaxx proteins expressed by GOIs processed by exocenous & endogenous pathways ie. balanced immune reponse
ie. Hu IV, CMV in hase I or II;
ie. PRRS & SIV
VEE (*alphavirus) |
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Term
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Definition
plasmid contructs: can be coated onto gold particles and delivered into skin by "gene gun" or injected naked into skin or muscle
particles processed by APCs ie. Langerhan cells
Issues: Induce CMI, humoral (IgG), secretory (IgA) immune response
safety: some concern for insertiona mutagenesis, autoimmunity to DNA
DNA vaxx candidates:
WNV-Innovator DNA vaxx - no published data
H5N1 AI: IM or ID(intradermal)
EIV: liposomes: intranasal |
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Term
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Definition
BSL1: agents w/ NO dz threat to humans
BSL2: agents capable of infecting humans by infestion, mucous membranes, sharpes (ie. salmonella)
BSL3: agents w/ serious & lethal consequences & transmitted by aerosol (ie. Hantavirus)
BSL4: highly lethal domestic/exotic agents transmitted by aerosols or unknown means (ie. Ebola, Hendra, Nipah viruses) |
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Term
| Oversight for animal use & safety |
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Definition
IACUC (institutional Animal Care & Use Committee - labs using animals in xs or research
IBC (Institutional Biosafety Committee) - Lab safety overseen |
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Term
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Definition
Pachecko's & poloma virus dz of psittacines - herpesvirus, & polyomavirus in the LIVER
EEE in brain but NOT blood when neuro signs present
BRSV difficult to isolate from dead animal (very labile)
Rota shed in greatest quantities (>10^9 particles/g) during first 3-4d of illness, then rapidly declines |
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Term
| Psittacines: Gross & histo lesions |
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Definition
Budgerigar: polyomavirus - basophilic INIB but not clearly visible (whole virus)
Conure: Pacheko's dz (herpesvirus) = acidophilic INIB present, also stained Ag (viral particles) |
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Term
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Definition
aborted fetuses - focal necrosis, INIB in liver indicative of herpesvirus ie. EHV1, BHV1
PPV = PPV Ag in fetal lung
WNV/dead crows = virus in brain, also oral cavity, cloaca and feather shaft |
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Term
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Definition
VI in embryonating eggs, cell culture, and animals
ID - serum virus neutralization (SVN) is Gold Standard (others: Fa/IFA, ELISA, HI, CF, PCR)\
tissue examples: BT (bovine turbinate for Bovine Resp viruses,
MA104 & derivative MARC-145 for PRRS (monkey kidney);
fetal equine liver aborted late gestation = EHV1 |
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Term
| NI (neutralization index) |
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Definition
the difference in logs btw end pts of control (normal, Ab-free serum) & test (Ab-pos) serum
*NI of 4(+) is considered pos for most viruses! |
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Term
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Definition
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Term
Demonstrating viral Ag in tissue by IHC
(examples) |
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Definition
TGE: villi of gut
PRRS: lungs of pigs
Parvo: lungs of fetal swine
Rabies: brain
PRV: palatine tonsils
CDV: conjunctiva & vaginal impression smears |
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Term
| Demonstration of virus by EM |
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Definition
| Sensitivity and specificity of neg staining can be incr by immuno-electron microscopy ie. adding virus specific Ab to sample prior to pelleting |
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Term
| EM neg staining examples (by clinical symptoms) |
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Definition
viruses causing vesicular dz in cattle/swine: FMD, VSV, Bovine mammalitis, Pox
Enteric dz: Rota, Corona, Norwalk |
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Term
| PCR & representation differential analysis (RDA) |
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Definition
RDA, a PCR techniques useful in IDing unknown pathogen uses RANDOM primers: NA extracted from normal tissue & dz'd tissue
PCR is run w/ random primers: amplicons appearning in dz'd, but NOT normal tissue may represent NA of unknown pathogen |
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Term
| Serological ID of virus infection |
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Definition
Detection of IgM (recent infection) or IgG in previously naive animals
Demonstration of rising titer (4-
(*Reciprocal of dilution (ie. 1:16 = 16))fold (+) increase) over a 10-14 d period |
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Term
| Specific serological tests |
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Definition
SVN
ELISA (IgM, IgG)
Agarose gel diffusion ie. COGGINS TEST for EIA
HI
CF |
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Term
| SNV for detecting and quantifying AB |
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Definition
Note: SVN can be used to ID isolated viruses using known Ab or used to assay for specific Ab as by using known viral Ag
1. serum to be assayed is serially diluted in 2-fold increments, and constant amounts of each dilution added in duplicate to wells in microtiter plate
2. constant amount of known live virus added to each well
3. serum/virus incubated @ 37oC ~1 hr & cells are added
4. MP wells examined for presence or absence of virus activity @ ~3 d
2^x = titer (ie. 2^6 = 64) |
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Term
|
Definition
1. unknown virus
2. virus specific Ab
3. to determine add cells (CPE = no SVN, normal cell monolayer = SVN) |
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Term
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Definition
if increase ID virus -> LOWER titer & DECREASED sensitivity
If decr virus ID -> Sensitivity would be DECREASED
*NOTE: Specificity is INVERSE of Sensitivity!!!! |
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Term
| Hemagglutination Inhibition: Ab |
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Definition
used with viruses that have proteins taht agglutinate RBCs ie. IV, some PI viruses, flaviviruses, some Parvo, etc
HI can be used like SVN to ID viruses or detect Ab: HI differs from SVN in that it uses a different indicator system for detecting Ag, Ab interaction
same as SVN but inhibition of HA vs. CPE determines if Ag/Ab reactions occured
Virus + RBCs -> Mat = agglutination
Virus + Ab + RBCs -> button = NO agglutination
HA activity is relative NOT absolute as in quantifying virus infectivity (ie. ID50s/ml) |
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Term
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Definition
like SVN is used to ID virus or detect Ab - difference is the indicator system used to detect Ag, Ab interaction
Test syetme: Ag, free C' (guinea pig serum), heat inactivated test serum (destroys any pro C' activity)
Indicator system: RBCs, Ab specific for RBCs (hemolysin)
Test system:
If Ab is present it will bind to Ag & fix C'
If absent -> Ag + free C'
Indicator system:
RBCs lyse only in presence of free C' & anti-RBC serum
Test system: no fre C' -> Indicator system: RBCs reamin intact
Test system: Free C' -> indicator ystem: Lysis of RBCs |
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Term
|
Definition
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Term
|
Definition
similar format used for ID WNV infeciton in horse.
1. Ab on plate is treated w/ WNV Ag
2. IgM in horse serum will bind to Ag & be detected by labeled 2o Ab |
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Term
| hemagglutination Inhibition: Ag |
|
Definition
HA activity is designated as # of HA units/unit vol
HA titers of stock preparations are relative b/c different assay conditions give different results |
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Term
|
Definition
major hosts: Canidae, Felidae, Mustelidae, Procyanidae, Viverridae, Ciroptera
Endemic w/ exceptions: AUS, New Zealand, Great Britian, Ireland, Hawaii, Japan
Rabies cases in USA predominantly in wildwilve (90%) & domestic animals (10%), human cases in US are rare but ~ 50000 WW
species distribution: raccoons > bats > skunks > fox > cats > dogs > cattle
cases in sheep, goats, horses & mongoose
Rabies in swine, rodents, squirrels is RARE |
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Term
|
Definition
Wild type = "street"
attenuated = "fixed"
stability in environnment is variable
negri bodies
"anti-messenger" group (- polarity) |
|
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Term
| Rabies classification: Rhabdiviridae |
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Definition
*Vesiculoviurs (VSV, fish viruses)
ephemerovirus (bovine ephemeral fever)
novirhabdovirus (infectious hematopoietic necrosis virus in salmonids, viral hemorrhagic septicemia virus, snakehead virus)
*Lyssavirus (rabies, bat lyssavirus)
unclassified (mostly fish viruses) |
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Term
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Definition
7 genotypes designated by number and based on % nucleotide homology and aa sequence of the N protein
4 proposed genotypes: Aravan, Irkut, Khujand, and West Caucasian bat virus
1 classical rabies virus
2 bat rabies virus
3 Mokola virus
4 Duvenhage virus
5,6 European bat lyssaviruses 1 and 2
7 Australian bat lyssavirus
Genotypes 1,3,4,5,6,7 cause hu dz (all but 2)
genotypes subclassified into biotypes (species specific) |
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Term
|
Definition
7 genotypes designated by number and based on % nucleotide homology and aa sequence of the N protein
4 proposed genotypes: Aravan, Irkut, Khujand, and West Caucasian bat virus
1 classical rabies virus
2 bat rabies virus
3 Mokola virus
4 Duvenhage virus
5,6 European bat lyssaviruses 1 and 2
7 Australian bat lyssavirus
Genotypes 1,3,4,5,6,7 cause hu dz (all but 2)
genotypes subclassified into biotypes (species specific) |
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Term
|
Definition
RV biotypes circulate in specific animal populations - species vary in susceptibility to biotypes
Biotypes are distinguished by differences in nucleotide sequences in G GENE, and/or G-L region (minor differences also in N gene)
Variants w/in biotypes are distinguished by MAB (monoclonal Ab) panels specific for N PROTEIN & nuceotide sequencing |
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Term
|
Definition
Little Brown bat
Silver-haired bat |
|
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Term
| Summary of Rabies pathogenesis |
|
Definition
entry via bite
replication in myocytes followed by entry into PNS thru ACH R & axonal movement to CNS where other Rare uilized
CNS:
limbic system involved fist (loss of cortical control ie. furious form),
neocortex (drum, paralytic forms)
death via Respiratory arrest but NOT prior to CENTRIFUGAL SPREAD to peripheral organs ie. Salivary gls
movement from CNS by peripheral nerves to internal organs, cornea, salivary gl, nerve bundles of sensory hairs
virus can be in saliva up to 10 ds before overt signs - >10d quarantine period in bite cases |
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Term
| Rabies Clinical presentation |
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Definition
1. exposure via bite/scratch,IP 2-3 wks to 6 mos, *yrs
2. change in temperment, animal does things it normally doesnt ie. loss of fear of humans by wildlife
3. furious from ie. aggressive behavior, fursion leading to "dumb, paralytic" form, or just dub & paralytic form. *Death w/in ~2-14 d
additional overt signs: cannot swallow, protrusion nictitating mebrane, ptyalism, hyperstheia, self mutliation, pica, changes in vocalization |
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Term
|
Definition
presumptive - abnormal behavior
Definitive: FAT on brain smear impression: brain stem, cerebellum, hippocampus, excellent site
- if neg then sucking mouse IC inoc test (MIT) & observe 21-28 d: FAT on brain smears of mice w/ CNS signs including death
Potantial alternatives to MIT
a. VI using BHK or Neuroblastoma cells & subsequent ID ie. FAT
b. RT-PCR: used w/ some success on samples not suitable for FAT, pos test meaninful but neg NOT
4oC, 50% glycerol in saline preserves brain where "cold chain" cannot be maintained |
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Term
|
Definition
1. population mmgt - animal control, vaxx
2. dogs, cats - killed vaxx in US, Canada:
canarypox vectored feline rabies liscensed for cats
MLV: low & high egg passage still used in some countries but NOT USA (safety reasons)
Wildlife species
1vectored vaxx (oral): modified vaccinia virus containing rabies virus gene "G" that encodes the envelop glycoprotein - used successfully in baits for oral vaxx of raccoons, coyotes in US |
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Term
| Rabies: Requirements for international movement of dogs |
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Definition
proof of vaxx
VN test (some countires req 2 consecutive tests at 12 wk intervals):
i. RFFIT (rapid flourescent focus inhibition test)
ii. FAVN (flourescent Ab virus neutralization test) ~OIEKSU VDL
Microchip ID's by Australia, Hawaii, New Zealand, St Kitts-Nevis
Quarantine req upon arrival varies (1-6 mos)
always check reqs at consulates for each country |
|
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Term
| Vector-borne encephalitides |
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Definition
WEE, EEE, WNV, SLEV, LACV, VEEV, JEV, TBE & Louping Ill
WEE/EEE/WNV/SLEV = Cx & amplifying hosts = birds
Favi- WEE, EEE, SLEV, JEV, TBE & Louping Ill
LACV-Bunya
VEEV, EEE- Toga
JEV- Cx; Lg birds, pigs
VEEV- multiple; sm, lg mammals & birds
LACV- Ae, sm mammal
TBE, Louping Ill- Ixodes, sm mammal
*JEV- significant swine repro pathogen
*TBE- Central EU & Asia (distinct strains)
LISpain & British Isles - dz in humans, sheep, + horses
*Highland Jvirus closely related to EEE = SE USA
*Cx tarsalis, pipens feed on hu when no bird hosts avaialble
California group (ie. LACV) - encephalitis in humans & chipmunks: Aedes triceriatus "Eastern tree hold mosquito"
JEV- encephalitis in humans & horses - "arthropod virus of people"; mosquitoes are very efficient varriers |
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Term
| Other zoonotic vector-brone viruses |
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Definition
DEN (flavi)- Ae aegypti, humans (other mammals) - fever, hemorrhage, shock (human)
CHIK (toga)- Ae, humans/primates - severe arthritic symptoms (humans), dz in primates - FOREIGN
YFV (flavi): Ae, haemoagogeus, humans/primates - generalized hemorrhage, rare encephalitis (humans); dz in primates - FOREIGN
CO tick fever (reo)- D. andersoni, sm mammal - NO Dz
RVF (bunya)- Ae/multiple afterward, ruminants - generalized hemorrhage, hepatitis, retinitis, rare encephalitis (hu); hihg mortality in ruminants - FOREIGN
*DEN is MOST infective arthropod borne vector of humans: mosquito-man-mosquito (Af = mosq-monkey-mosq in rainforests) ); wide range of mammilian sp incl 5 bats ie. S America: Sylvatic cycle
one genus - Artivius (bat sp) - nests in high areas close to human habitation
Ae where DEN is endemic - becomes active when bat is resting -> PI? Carrier-state? Dry period?
CHCK- also mosq-man-mosq |
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Term
| Non-vector-borne zoonotic viruses |
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Definition
,antaviruses (bunya)
ie. Sin nombre, aka 4 corners virus
- sm rodents (mice, rates): saliva/urine/feces; retains infectivity , geo distinct hantaviruses have own host
ie. SN virus/4 corners virus: Peromyscus maniculatus
ie. NY virus: Peromyscus leucopus
- generalized, *focus on lung (human)
Old world hantaviruses
sm rodents
Hantaan virus (Korea) - host Apodemus sp - generalized, hemorrhage, w/ *focus on kidneys (human)
LCM virus (arena)
sm rodents (mice, hamsters) - aysmptomatic, meningitis (humans); unthriftiness, type 3 (animals)
*Hantaviruses (new & old world) outbreaks assoc w/ environmental conditions favoring large increases in rodent populations
Monkey B virus (herpes)
Macaques: bite/contact w/ open wounds ie. scratches, sores - ascending paralysisn, encephalitis (humans); vesicular lesions (animals) |
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Term
| Criteria for vector competency |
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Definition
1. the vector must have access to feed and feed on hosts that support virus replication at levels that are infective for the vector
2. must be able to transmit the virus in quantities that will infect animals on which it feeds |
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Term
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Definition
~5% IR = 10^4 Cx; 10^5.5 Ae (~diff of 1.5 logs)
*NOTE: VEE = Horse is AMPLIFYING Reservoir host
WNV, WEE, EEE- horse is DEAD-END host |
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Term
| General paradigms for maintenance and transmission |
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Definition
Mosquito-bird-mosquito: commonly assoc w/ viruses vectored by Cx -
ie. WNV, JE, SLE
Mosquito-mammal-mosquito: commoly assoc w/ viruses vectored by Ae
ie. YFV, DEG, - assoc w/ hemorrhagic dz
ie. LCV (tree hole mosquitoes) assoc w/ encephalitis
Tick-mammal-tick
ie. Tick-borne encephalitis virus (Central Eurpoean, Far Eastern viruses), Louping Ill |
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Term
|
Definition
generally occurs west of the MS River (closely related w/ Highlands J virus in E US)
Pirnciple epidemic vector is Cx tarsalis birds are the 1o host but there is a shift in feeding pattern from bird to mammal in late summer/early fall - exposure ends w/ first killing frost
overwintering (interepidemic survival) probably mosquito
some Ae spp can serve as BRIDGE VECORS in traansmission to humans & horses |
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Term
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Definition
Ae sollicitans, vexons, Coquiiettida perturbans
occurs along Atlantic & Gulf coasts & Upper midwest along MS River
(also Cliseta melanura)
OW probably mosquito, migratory bids?
Larger bids ie. Emu, pheasant, others |
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Term
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Definition
Maintenance/amplifying vectors (Cx) ->
Bird-mosquito-bird (enzootic, epizootic)
Rabbits, squirrels, chipmunks ->
Bridge vectors: Cx, Ae
-b> Dead end hosts: humans, horses, other mammals
*Crows & robbins serve as 1o amplifying host, OW in mosquito, possibly continuous in infection in birds
WNV is PI in HAMSTERS!!! |
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Term
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Definition
Sm mammal reservoir -> Ae triseriatus (ie. eastern tree hole mosquito)-> Human = DEAD-END host (most severe in children
*breeds in tree holes, tire dumps, containers |
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Term
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Definition
epidemic forms not in US but periodically emerge in South America & move N to US border as in early 1970s
-6 major variants: I, II, III, IV, V, VI
subtype I is divideded into 6 variants: endemic ID, IE, IF
epidemic IAB, C variants arise from mutations of endemic variants
Subtype II is endemic in Fl everglades
Killed vaxx |
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Term
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Definition
Sylvatic cycle maintained in South America by Haemagogus sp in canopy; also ticks in dry season; Dz in NW Monkeys
Urban cycle: Ae aegypti has adapted to hu environment although it can be found in forested areas. Ae aegypti is also primary vector for DENG (Amyplifying!) |
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Term
|
Definition
TBE viruses occur in Central Eu, Asia
(Ixodes persulcotus, rincinus)
Louping Ill in UK, Ireland has similar cycle in sheep
Virus overwinters in tick |
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Term
|
Definition
1. Wet Season: virus infected flood water- Ae sp
2. Dry season: rains begin
3. Amplification -> HIGH VIREMIA
then Cx, other Ae, sp. etc involved |
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Term
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Definition
Mosquitos: NJ light traps (abundance)
CDC light traps, oviposition traps: mosquitoes separated by sex, sp; females pooled in groups of ~50 and tested for viruses using ELISA Af capture &/or RT PCR, VI using suckling mice or cell mice or cell culture
Chicken sentinels - bled wkly assayed for Ab (ie. IgM for WNV, SLE)
Other - WNV & dead bird collection
Mosquito abundace/prevalence data to local health authorities (moquito control-insecticides, larvacides, elimination of breeding sites) |
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Term
| Clinical presentation of WEE< EE, WNV in horses, Dx, Control |
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Definition
IP ~2-10 d
symtpoms: in-coordination, circling, sawhorse stance, head pressing, pharyngeal & esophageal paralysis, photophobia/blindness, hyperestheisia, stupor, coma, recumbance & opisthotonus
druation of symptoms ~4-9 d
some rule-outs: EHV1, rabies, equine protozoal myeloencephalitis (PM)
Dx & control:
Antemortem: virus specific IgM ie. WNV in serum, rising IgG titer
VI not effecitnt for WEE, WNV, EEE as viremia is generally absent by time noticed
RT-PCR of CSF possible: PCR of nasal swab can be used to rule out equine herpesvirus; PCR of saliva for rabies but virus not always present (hazardous procedure)
Postmortem: VI, RT-PCR brain tissue
Control: killed (WEE, EEE), vectored, plasmid vaxx (WNV)
Notes: EEE virus will infect & kill emus, pheasants, turkeys, and other lg birds. EEE can be transmitted by *pecking. Small passerifrmes are 1o hosts & dont die.
WNV will also cause fatal infection in domestic geese. |
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Term
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Definition
Epi cycle: IAB, *IC - many mosquitoes - mosquitoes represent opportunistic, mammalophilic, ornithophilic spp-> Lg mammals & birds
Enzootic cycle: ID, IE, IF - Cx (melanoconin) spp -> sm mammals
VEE mutations in the 5' NTR & E genes
*IC evolves from ID |
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Term
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Definition
VEE is similar to the other equine encephalitis viruses EXCEPT:
- viremia can reach 10^9 PFU/ml ie. horse serves as an AMPLIFYING host
- virus recovrered from nasal washing, eye washings, urine ie. contact infection is a possibility as virus can access CNS via olfactor nerve
- multiple organ systems infected
CF ~50-80%!
Epidemic forms of virus not currently US but potential exists
Killed vaxx available |
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Term
| Classification: Togaviridae |
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Definition
alphavirus (~40 viruses transmitted 1o by mosquitoes) - at least 7 Ag complexes
WEE, EEE, VEE complexes > EEE complex (EEE & Highlands J virus)
Fish viruses: salmonid pancrease dz virus
sleeping dz virus of trout
Rubivirus (German measels virus) |
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Term
| Classification: Flaviviridae |
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Definition
Flavivirus (~70 viruses transmitted by mosquitoes & ticks: mosquito-borne Ag groups
-YFV, DEN, JEV (JE group (JE, WN, SLE viruses)
-tick-borne Ag groups (mammalian & seabrid groups)
Pestivirus (BVD, CSFV, BDV) - not vectored
Hepacivirus (Hep CV) - not vectoreed |
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Term
| Classificaiton: Bunyaviridae |
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Definition
Orthobunyavirus - >150 viruses distrubted among 18 antigenic groups - most are mosquito vectored, some by ticks & culicoiddes
- important groups/viruses: California group (LACV), Bunyawera group (Cache Valley virus), Simbu group (Akabane virus))
Phlebovirus: RFV
Nairovirus (NSD, CCHF0) - ticks
Hantavirus: not vectoreed by arthropods |
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Term
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Definition
rapid replication/lysis; latency assoc w/ sensory ganglia, lymphoid tissue)
-EHV1 (Eq abortion virus)
EHV4 (eq rhinopneumonitis)
EHV3 (Eq coital exantehma)
-EHV 6,8,9 (latter very similar to neurological strians EHV1)
Gammaherpesviruses (slow replication; narrow host range; lymphotrophic)
- EHV2,5,7
2-assoc w/ mononucleosis-like syndrome of foals
5- progressive pulmonary fibrosis syndrome
7- encephalitis of donkeys
EHV1, VEE + URT
Others- NOT URT (WNV, EHV4, EEE, WEE, etc) |
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Term
|
Definition
abortion usually late term w/ fetus in relatively good condition; "ABORTION STORMS" occur in susceptible populations w/ rapid spread of virus via contact w/ contaminated conceptus; perinatal mortality:
focal necrosis in liver, interstitial pneumoni, etc
Respiratory dz
encephalomyeltiits (assoc w/ specific strains): vasculitits of cerebral vessels, thrombosis, neurla dgeneraation |
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Term
|
Definition
profuse serous nasal discharge becoming mucopurulent-
common in foals as maternal Ab declines, recrudescence common throughout life
rarely assoc w/ abortion |
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Term
|
Definition
| self-limiting vesicular, ulcerative lesions of genital mucosa and surrounding skin, occasionally on lips, muzzle, teats |
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Term
| Dx & control of Eequine HV |
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Definition
common rule-outs; vector-brone encephalitis viruses , rabies, EPM
VI, PCR, SEroligcal: PCR of nasal swab is effective
Mmgt: isolation; infection control; consider latency |
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Term
|
Definition
Usually asymptomatic, abortion w/in month of infection (strain dependent), fetus commonly autolyzed, abortion storms occur
Others-
commonly presents as URTI ie. conjuncivitis, rhinitis, nasal discharge: foals sometimes develop fatal bronchointerstitial pneumonia
*edema: palpebral, ventral, hind leg; assoc w/ vascular lesions: sm segments of intestinal necrosis in young
pleural & pericardial effusions
PI common in stallions**, lasts mos-lifetime iel. STALLION = RESERVOIR: PI NOT recognized in mares, foals prior to puberty & geldings - ie. toestosterone dependent: vaxx of foals prior to puberty inhibits PI!!!
Transmission via aerosols, fomites, contact; and veneral via PI stallion/AI
Dx, control: VI, PCR, serology
Live & killed vaxx
Management |
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Term
|
Definition
A/Maiami/2/63 (H3N8); Eq type2, most important worldwide (this is the subtype w/ mutations now in North American dogs!):
-divergence of H3N8 into Eurasian & North American lineages ie. FL, KY - Ag drift
- URT dz more explosize & rapidly spreading vs. EH4 & EHV1
mortality rare - but in 1989 Mongolian/China eq H3N8 outbreak; morbitditiy:mortality::80:20%: virus evolved from Avian H3N8, 6 or 8 segments of Avian origin*
control via vass:
i. Cold adaptive
ii. Canarypox vectored vaxx
Note: A/Prague/1/56(H7N7); eq type 1 has not been isolated for yrs! |
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Term
| ERAV (Eq Rhinitis A virus) |
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Definition
member of Apthous genus (~FMD); present as fever, nasal discharge, pharyngitis (persistent cough 2-3 wks), lymphadentitis, bornchitis (~EHV & EAV):
virus shed via nasal secretions & ruine
transmitted by aerosol & close contact
Old & New world camelids susceptible: abortion, wasting dz in *New world camelids: virus infection of islet cells of pancrease (note: some strains of coxsackie virus also infect/kill islet cells)
Dx & control
-dz is *self-limiting
information lacking on risk to camelids housed in close proximiting to infected horses |
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Term
|
Definition
lentivirus causing acute to chronic infectious dz of horses (donkeys, mules) characterized by recurrent bouds of: fever, anemia, thrombocytopenia, icterus, edema: anemia not generally seen until recurrent episodes
GN may eventually occur (DTH3)
mortality rates can be >50%
Transmission iatrogenic or mechanical: biting insects ie. Stomoxys spp, Culicoides spp & other biting flies (esp -successful transmissino 1:7 attemps via Horse fly)
Control-
ID infected via COGGINS test or ELISA, can confirm by PCR
Quarantine new stock 45 d & retest
stable infected horses >200 yrds from uninfected
no vaxx available to US!: role of Neutralizing Ab unclear!~ |
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Term
|
Definition
Rhabdovirus; causes self-limiting vesicular dz of horses, cattle, swine, lesions ~ fmd
mechanical transmission by fomites & biting insects (outbreak probably initiated via biological vector)
- Lutzomyia (sandflies), Simulidae (black flies), culicoides (midges) can serve as bioological vectors
-VSV retains infectivity few ds moist, cool conditions w/ organic material ie. milking machines
zoonotic IV-like illness, vesicular lesions in mouth reported
*Disappears after Killing frost!!!
No vaxx! |
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Term
|
Definition
| Eq pappilomaviruses (warts) & sarcoids (strong evidence due to bov papillomavirus 1,2) |
|
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Term
|
Definition
emerged 1994 Aus, member of Heniphavirus of Paramyxoviridiae
-zoonotic (h*HIGH human mortality)
-FRUIT BATS (megachroptera) are natural reservoir
-ARS (clear to sero-sangiuinous), edema, cyanosis, CNS involved (head pressing, ataxia), death ie. HIGH MORTALITY
*virus SHED PRIO to clinical signs!!!
BSL4!!!!!!!!!!! |
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Term
|
Definition
FAD: an orbivurs of the Reoviridiae: severe systemic dz: pulmonary & cardiac forms, high mortality
Affects Eq, mules, donkeys, zebras (dogs that eat carcasses)
vectored 1o by Culicoides
Vaxx available (9 known serotypes)
(pullmonary-> foaming nasal discharge; Cardiac -> severe swelling/edema & sero-sanguinous discharge from mucosa outles/eyes, etc |
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Term
|
Definition
envelopd glycoprogies: gA-gE
biological characteristics: vesicular lesions of mucosa & skin; gerneralized infection w/ focal necrotic lesions common; also affect RT, Repro, CNS
latency w/ intermittent shedding (some *Beta can be continuously shed)
genreally m ore severe in young v. old, less severe in natrual nost
INIB
cool, moist environment promotes survival
6 subfamilies : alpha, beta (cytomegalo viruses), gamma (lymphotrophic), alloherpes (channel catfish virus), malacoherpes (oysters) |
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Term
|
Definition
+sslinear RNA, enveloped: major env proteins: E, M, GP5 (alpha recep)
Biological characteristics:
-asymptomatic PI in natural hosts
sme arteriviruses: EAV, PRRSV, *SHF (Simian hemorrhagic fever) virus
Note; reston virginia ebola (filoviridae) outbreak was originally through tot be SHF virus - reston originated in the phillipines where it has since affected pigs, humans (no deaths as is rule w/ Af isolates). Reston virus causes repro failure & severe Resp dz in pigs.
FOREGIN |
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Term
|
Definition
enveloped, helical, segmented -ssRNA
Biological characteristics of type A IV:
high rate of mutation (Ag drift)
genetic reassortment (Ag shift)
3 genera:
IV (8 segments): evolved into 5 lineages ie. gulls, swine, human, old horse & new horse (virus evolvedvirus evolved from avian virus)
-3 types: A,B,C based on internal proteins: subtypes of A based on H & N
Thogotovirus (tick transmitted)
Isavirus (infectious salmon anemia virus) |
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Term
|
Definition
sm naked +ssRNA - very stable outside host
6 established genera
aphthovirus: FMD not in horse, ERAV
Enterovirus: swine vesicular dz (FAD), coxsackie viruses ie. handfoot-and-mouth dz, human poliovirus, human & bovine rhinoviruses
Cardiovirus: encephalomyocarditis virus
Teschovirus: porcine TV1 (formerly porcine entero virus1), aka pig polio (Teschen dz, Talfan dz in Eu)
Hepatovirus: Hep AV |
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Term
|
Definition
enveloped, DIPLOID RNA ie. 2+ RNA strands covalently linked; major env protein s SU
Biological characteristics
reverse transcriptase (note revTET has -both R & D pol activity)
-PI (latent)
Genera:
alpha, beta, gamma, omega, epsilon (oncoviruses)
Lentivrus (EIA, HIV, FIV, CAEV)
Spumaretrovirinae (significance of members unknown) |
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Term
|
Definition
-ssRNA, 1 envelope protein = G
Genera
Lyssavirus (rabies)
vesiculovirus (VSV): 2 serotypes in US
i. VSV-NJ (New jersey)- iso in 1926 from cattle, most common
ii. VSV-IN (indianta) isolated 1925 from cattle, last isolated 19656 - uncommon: variants w/in serotypes
Ephemoerovirus (bovine ephermeral fever FAD, arthropod transmission)
Novirhabdovirus (infectious hematopoetic necrosis virus of salmoids, viral hemorrhagic septicemia virus, snakehead virus) |
|
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Term
|
Definition
naked, circular dsDNA
- CANNOT grow in cell cultre
-typed by nucleotide sequences (PCR) & host specificity
Warts in all spe, some can lead to maligancy ie. bov 4, rabbit & hu types
Eq sarcoids
-histo: ~ fibrosarc
-bov1,2 are probable cause: exerimental inj results in eq sarcoid but unlike natraully occuring sarcoids they regress spontaneously*; DNA of the bov viruses have been detected in eq sarcoids |
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Term
|
Definition
pleomorphic, lg-med size, env, *helical, -ssRNA: env contains 2 glcoproteins: HN, H, G depending on virus; F (fusion protein)= virulence actor
2 subfamilies-
Pneumovirinae: BRSV (pneumovirus), Turkey rhinotracheitis (metapneumovirus): severe resp dz
paramyxocirinae (5 genera)
respirovirus: bov PI3, Sendai PI1
Avulavirus: : NDV - lentogenic, mesogenic, velgenic (FAD)
Rubulavirus: canine PI5 (formerly PI2), Simian PI5 (~canine PI5) hu PI2, por rubula virus (FAD), aka blue eye (Mexico), Human Mumps virus
Morbilivirus: CDV, Rinderpest (now eradicated), Measela (the medipest group), Peste de petitie ruminants, morbilliviruses of seals/dolphins/porpoises
Heniavirus: Hendra, aka eq morbillivirus, Nipah virus of pigs (BSL4 agents) both FAD |
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Term
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Definition
med, naked, 2-3 capsid layers, *SEGMENTED ds RNA, "wheel" appearance
5 genera
biological characteristics depend on genus:
arthropod-borne: Orbivirus: BTV, epizootic hemorrhagic dz of deer (EHD), AHS: Coltivirus Co tick fever virus, a zoonotic
Non-arthropod-borne:
Rotavirus (enteritis, mammalian sp)
Orthoreovirus: reoviruses of rodents; avian orthoreoviruses; tenosynovitis, arthritis most common effects but others incl resp, GI, liver, runting etc. |
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Term
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Definition
Lg-med naked nucleocapsid, dsDNA - unique penton fibers on vertices w/ HA activity
gerna incl:
Mastadenovirus: CAV1,2; Eq adenovirus- resp dz in SCID foals
Aviadenovirus: Qual bronchitits virus
Atadenovirus:: odocoileus adenovirus 1 (fata hemorrhagic generalized dz, west coast); egg drop syndrome (egg defects ~ IBV), adenoviruses of reptiles)
Siadenovirus: hemorrhagic enteritis of turkeys |
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