Family Adenoviridae • ds DNA • Only DNA family forming basophilic intranuclear inclusion bodies • Hemagglutinates • Environmentally stable but easily inactivated by disinfectants • Penton fibers project from vertices • Genera Mastadenovirus=mammalian, 1 penton fiber per vertex • Genera Aviadenovirus=avian, each penton fiber is bifurcated • All have narrow host range & mostly subclinical infections • Associated with long periods of latency
Infectious Canine Hepatitis Syn: ICH, Rubarth’s Dz • Etiologic Agent: Canine adenovirus 1 • Host: Family Canidae (domestic & wild) & Ursidae (bears) • Distribution: worldwide • Transmission: mainly ingestion of urine, feces, or saliva, also conjunctival or aerosol routes • Pathogenesis: initial infection in tonsilar crypts & Peyer’s patches • Clinical Feature: viremia leading to hemorrhages & necrosis of target organs (liver, kidneys, spleen, lungs), mostly asymptomatic, can lead to Corneal Edema (blue eye), Glomerulonephritis, DIC, Encephalitis (foxes) • Vx: inactivated & MLV CAV-1 used, cross-protection given with CAV-2 vx • DDX?
Canine Infectious Tracheobronchitis Syn: ITB, Kennel Cough • Etiologic Agent: CAV-2 (also canine parainfluenza virus 2, Bordetella bronchiseptica, Mycoplasma cynos) • Host: Canines • Distribution: worldwide • Transmission: highly contagious via aerosolized microdroplets • Pathogenesis: self-limiting (2 wks) upper respiratory disease • Clinical Feature: nonproductive cough • Vx: CAV-2 MLV • DDX?
Equine Adenovirus Infections • Etiologic Agent: Equine adenovirus 1 • Host: horses, mostly Arabians due to T&B cell immunodeficiency • Distribution: worldwide • Transmission: • Pathogenesis: fatal, horses susceptible to a wide range of pathogens as maternal antibodies wane (usually within 3 months) • Clinical Feature: bronchiolitis and pneumonia • Vx: • DDX?
Family Retroviridae • Enveloped, diploid [+] sense ss RNA, does not serve as mRNA • Contains Reverse Transcriptase • Replicates in cytoplasm & nucleus, NO inclusion bodies • All RNA oncogenic viruses=Retroviridae (leukemias, lymphomas, sarcomas) • Fragile viruses inactivated by detergents but resistance to UV light • Gag gene (capsid), pol gene (reverse transcriptase), env gene • Genera (Alpha, Beta, Gamma, Delta, Epsilon)-retrovirus, (Lenti, Spuma)-virus • Type A=intracellular noninfectious->Type B=extracellular eccentric core, Type C=central core, oncogenic, Type D=tubular core • Acute transforming=[V-onc+], replication defective • Chronic transforming=[V-onc-], cause cancers late after infection
Bovine Leukemia Syn: Enzootic bovine leukosis • Etiologic Agent: Deltaretrovirus [v-onc+] • Host: cattle • Distribution: worldwide, seen more in dairy vs. beef due to lifespan • Transmission: via blood lymphocytes (horizontal & vertical trans.) • Pathogenesis: target cells=B lymphocytes, outcome=failure of infection, asymptomatic infections, permanent infection, infected cattle developing lymphosarcoma in cattle 4-8 yrs old (1% infected) • Clinical Feature: high antibody levels easy to detect • Vx: No, test & slaughter animals over 6 months old • DDX? Compare to Sporadic Bovine Leukosis (SBL)=cattle<3yrs old, unknown agent. Calf form <6mo., enlarged lymph nodes, 100% fatal, Thymic form 6mo-2yrs, bloat & edema, 100% fatal, Cutaneous form 1-3yrs old, rare, skin plaques
Feline Leukemia & Sarcoma • E • Etiologic Agent: Gammaretrovirus, noncytopathic, v-onc-, Subgroup A transmitted cat to cat, p27 protein free in plasma & detected by tests • Host: domestic & some wild cats • Distribution: worldwide • Transmission: via saliva (grooming) & iatrogenic, continual shedding • Pathogenesis: multiplies in T& B lymphocytes & myeloid cells, FOCMA antigen present on transformed cells & FOCMA antibody lyses tumor cells via ADCC & complement activation • Clinical Feature: 1)most cats=self-limiting infection, 2)most at risk=persistent active infection (persistent viremia & immunosuppression), 3)latent infections=does not shed the virus • Vx: MLV and genetically engineered vx • FeSv associated w/fibrosarcomas in cats <5 yrs old, FeLV needed for replication
Avian Leukosis Syn: Big Liver Dz. • E • Etiologic Agent: Alpharetrovirus, [v-onc-], Subgroups A&B most important, C&D infrequent, E genetically inhereted & nononcogenic • Host: chickens (not turkeys) • Distribution: worldwide • Transmission: vertical or horizontal <5 days old=viremic for life, >5 days old=transient viremia due to antibodies • Pathogenesis: B lymphocytes in bursa of Fabricius • Clinical Feature: Lymphoid leukosis (big liver dz), Osteopetrosis less common & not neoplastic • Vx: terminate breeder stock, no vx • DDX? Without nerve or ocular involvement seen in Marek’s Dz.
Feline Immunodeficiency Dz • E • Etiologic Agent: Feline Lentivirus, Subgroups A-D (no cross-protection), test for p24 core antigen • Host: Domestic cats & some wild felidae, not zoonotic • Distribution: • Transmission: lifelong infection, via saliva in bites (free-roaming) • Pathogenesis: immunosuppression, tropism for helper T cells & MØ • Clinical Feature: Acute, Latent, and Terminal stages • Vx: questionable efficacy • DDX?
Equine Infectious Anemia Syn: EIA, Swamp Fever • E • Etiologic Agent: Equine lentivirus • Host: Equids • Distribution: • Transmission: transfer of blood (mechanically by tabanids, vertical) • Pathogenesis: replicates in macrophages & lymphocytes, lifelong cell associated viremia, vasculitis, anemia, glomerulonephritis • Clinical Feature: Acute 80% mortality, Subacute, Chronic, test via Coggin’s test & recommended destruction or isolation • Vx: • DDX?
Caprine Arthritis-Encephalomyelitis • E • Etiologic Agent: Caprine lentivirus • Host: goats • Distribution: worldwide • Transmission: vertically by colostrum & milk • Pathogenesis: multiplies in monocytes & macrophages • Clinical Feature: arthritis most common, Encephalitis 1-5 month kids (fatal), Interstitial pneumonia in adults (fatal), Mastitis • Vx: No, test & slaughter • DDX?
Family Rhabdoviridae • E • Bullet-shaped, [-] sense ss RNA • Antibodies directed against envelope G proteins • Defective interfering [DI] particles formed during replication with truncated genome • Thermolabile, sensitive to UV light, and readily inactivated by detergents • Some cause rapid cytopathology & others noncytopathic
Rabies • E • Etiologic Agent: Genus Lyssavirus, 6 strains in N.A. • Host: all warm-blooded animals (not birds), cats more susceptible than dogs, bats not a true reservoir host • Distribution: worldwide • Transmission: bite or scratch, also aerosol in bat caves, skunks have high prevalence & high quantities in their saliva, bats have a protracted clinical course • Pathogenesis: from inoculation site to ACh receptors centripetally to CNS, “furious” form in limbic system, “dumb” from neocortex replication, centrifugally down peripheral nerves (salivation) • Clinical Feature: death from respiratory failure, IP influenced by dose, strain, degree of innervation, site (distance) of innoculation • Vx: yes • DDX?
Vesicular Stomatitis (VS) • E • Etiologic Agent: Genus Vesiculovirus (Indiana, New Jersey=most common, & Isfahan serotypes) • Host: cattle & other ruminants, horses (unlike F&M), swine, humans • Distribution: Americas & Caribbean • Transmission: contact, ingestion, and mainly mechanical arthropod • Pathogenesis: systemic & viremic phase seen only in pigs & lab • Clinical Feature: vesicular lesions, profuse salivation • Vx: autogenous killed vx, questionable & gives + serologic status • DDX? Foot and Mouth disease (but horses don’t get that)
Bovine Ephemeral Fever Syn: 3-day sickness • E • Etiologic Agent: Bovine ephemerovirus • Host: cattle & water buffalo • Distribution: Africa, Asia, Austrailia (never in US) • Transmission: biologically transmitted via mosquitoes & Culicoides • Pathogenesis: Type 3 immune complex hypersensitivity, in buffy coat • Clinical Feature: sudden onset, dramatic recovery is pathognomonic • Vx: attenuated vx, also use vector control • DDX?
Family Picornaviridae • Nonenveloped linear [+] sense ssRNA • Do not produce inclusion bodies • Multiple serotypes without cross-protection • Very resistant in the environment = stable
Foot-and-Mouth disease [FMD] Syn: Aphthous fever, epidemic aphthae • E • Etiologic Agent: Aphthovirus • Host: cattle, sheep, goats, swine, buffallo, ruminants, NOT horses • Distribution: endemic in Asia, Africa, Mid East, and S. America • Transmission: inhalation of aerosols, feeding uncooked garbage • Pathogenesis: < 5% mortality rate “tiger-striped heart”, up to 2 yrs as a carrier state (no carrier stage in pigs) • Clinical Feature: Vesicles on tongue, lips, gums, palate, teats, etc., immunity is type specific & not life-long • Vx: inactivated & MLV where endemic, test & slaughter elsewhere, notifiabe dz., human infections are subclinical
Porcine Polioencephalomyelitis Syn: Teschen/Talfan Dz. • E • Etiologic Agent: Porcine enterovirus 1 • Host: Swine, usually in pigletts < 12 wks old • Distribution:Talfan more common & worldwide, Teschen = Czech • Transmission: ingestion • Pathogenesis: virus replicates in GIT without forming diarrhea, viremia spreads dz to CNS • Clinical Feature: CNS signs, teschen form mortality ~ 75% • Vx: not done in US, only done where Talfan form is • DDX?
Porcine Enteroviruses 2-11 • E • Etiologic Agent: porcine enteroviruses 2-11 • Host: swine • Distribution: • Transmission: • Pathogenesis: • Clinical Feature: seen with SMEDI, diarrhea & pericarditis • Vx: • DDX?
Avian Encephalomyelitits Syn: Epidemic tremor • E • Etiologic Agent: Avian enterovirus • Host: all birds • Distribution: worldwide • Transmission: fecal-oral route • Pathogenesis: • Clinical Feature: CNS signs, Mortality may be >50% • Vx: • DDX?
Encephalomyocarditis • E • Etiologic Agent: Cardiovirus • Host: humans, swine, monkeys, cattle, horses, rodents = reservoir • Distribution: • Transmission: fecal-oral route • Pathogenesis: pathognomonic cardiac lesions, esp. in R ventricle • Clinical Feature: sudden death, mortality can be > 100% in pigletts • Vx: inactivated given to sow to pass passive immunity to pigletts, mainly do rodent control • DDX?
Family Paramyxoviridae • Every member causes a respiratory dz. • Intracytoplasmic inclusion bodies • Pleomorphic virions with syncitia formation • H (hemagglutinin) = attachment • F (fusion protien) = penetration, important in persistant infections & cell-cell spread • N (neuraminidase) = enzyme • Genus Morbillivirus also intranuclear inclusion bodies
Bovine Respirovirus Disease Syn: Bovine Parainfluenza Virus 3 Disease • E • Etiologic Agent: Bovine respirovirus • Host: cattle & sheep • Distribution: worldwide • Transmission: awrosolization & contaminated fomites • Pathogenesis: high morbidity, low mortality, contributes to shipping fever complex • Clinical Feature: Hemagglutinates • Vx: MLV intranasal or parenteral vx, induces mucosal IgA antibodies • DDX? Infectious Bovine Rhinotracheitis
Newcastle Disease • E • Etiologic Agent: avian rubulavirus 1 with strains varying in virulence, Velogenic strains are highly virulent • Host: almost all avians (gallinaceous birds) • Distribution: worldwide • Transmission: aerosols & ingestion, virus shed during IP onward, persistant carrier state • Pathogenesis: Viscerotripic velogenic ND (exotic)=hemorrhages in GID & 100% mortality, velogenic ND (endemic)=no GIT lesions • Clinical Feature: Notifiable Dz • Vx: naturally occuring lentogenic (least virulent) strains given • Dz is zoonotic, but not threatening
Canine Rubulavirus • E • Etiologic Agent: canine parainfluenza virus 2 (CPiV) • Host: dogs • Distribution: worldwide • Transmission: aerosolized microdropletes • Pathogenesis: part of kennel cough syndrome, • Clinical Feature: does not multiply in macrophages, only URT • Vx: intranasal & parenteral vx • DDX?
Canine Distemper Syn: Hardpad Disease • E • Etiologic Agent: canine morbillivirus • Host: domestic & wild dogs, Ursidae(bears), Mustelidae(ferrets), and Procyonidae(raccoons) families, CNS infections in exotic Felidae • Distribution: worldwide • Transmission: inhalation • Pathogenesis: intranuclear & intracytoplasmic inclusion bodies • Clinical Feature: survivors have prolonged immunity, fever, leukopenia, GI & respiratory catarrh, pneumonic & CNS signs • Vx: MLV every 2-4 wks from 6 wks old, titer of >1:100 protects you • DDX? Infectious canine hepatitis
Rinderpest Syn: Cattle Plague • E • Etiologic Agent: Bovine morbillivirus • Host: cattle & buffalo (also seen in sheep, goats, swine) • Distribution: endemic in Asia, Africa, Middle East • Transmission: inhalation, oral, no carrier state • Pathogenesis: replicates in the palatine tonsils & lymph nodes causing destruction of lymphocytes • Clinical Feature: virus is excreted prior to showing clinical signs, morbidity & mortality ~100% • Vx: MLV, recovered animals have lifelong immunity • DDX?
Bovine Respiratory Syncytial Dz • E • Etiologic Agent: bovine pneumovirus • Host: cattle & sheep • Distribution: worldwide • Transmission: aerosolization • Pathogenesis: complete loss of ciliated epithelium, so 2° bacterial inf. • Clinical Feature: morbidity is very high, mortality is low, no hemagglutination • Vx: inactivated & MLV vx • DDX? Bovine Respirovirus Dx. & Bovine Herpes Virus 1 (IBR)
Family Orthomyxoviridae • Segmented genome w/genetic reassortment & defective interfering particles • Require host DNA transcription to replicate • Replication via ‘cap snatching’ in the nucleus • Type based on RNP & M1 matrix protein • Subtypes based on H (hemagglutinin) & NA (neuraminidase) • H antibodies prevent attachment, NA antibodies decrease spread but don’t neutralize free virions • Penetration via endocytosis, uncoating via M2 ion channel
Equine Influenza • E • Etiologic Agent: Influenza virus A: 2 types = A/equine/Prague/1/56/(H7N7), A/equine/Miami/1/63/(H3/N8) • Host: equines (not zoonotic) • Distribution: worldwide, very unstable virus in environment • Transmission: aerosolized, no carrier state • Pathogenesis: replicates in respiratory epithelial cells • Clinical Feature: high morbidity, rare mortality, acute, contagious, febrile respiratory dz, Hemagglutinates • Vx: inactivated bivalent vx., also use 30 day quarantine • DDX? Common cold
Swine Influenza Syn: Swine flu, Hog flu • E • Etiologic Agent: Influenza virus A, A/swine/Iowa/15/30/(H1/N1) • Host: swine, humans, and turkeys • Distribution: worldwide • Transmission: aerosolization, outbreaks most common in fall/winter due to indoor housing • Pathogenesis: replication in respiratory epithelium • Clinical Feature: herd disease, mortality low unless 2º bacterial inf. , Hemagglutinates • Vx: yes, but not good results so not widely used • DDX?
Avian Influenza Syn: Fowl Plague • E • Etiologic Agent: Influenza virus A, unstable virus with changing genome, some are zoonotic • Host: turkeys more than chickens, migratory water fowl = reservoir • Distribution: • Transmission: aerosolization, ingestion • Pathogenesis: replication in respiratory & GIT, highly pathogenic avian influenza A virus (HPAI) causes viremia • Clinical Feature: respiratory, enteric, and/or CNS lesions, hemagglutinates • Vx: no, quarantine & eradication, Notifiable Dz • DDX? Newcastle Dz.
Family ReoviridaeReo=Respiratory Enteric Orphan • 3 concentric capsid layers • dsRNA divided into 10-12 segments • Perinuclear inclusion bodies • Cytoplasmic replication • Genetic reassortment
Bluetongue Syn: Soremuzzle • E • Etiologic Agent: Ovine orbivirus, US=serotypes 2, 10, 11,13, 17 • Host: sheep & white-tailed deer • Distribution: worldwide • Transmission: noncontagious, arthropod-borne seasonal dz (Culicoides=biological vectors) • Pathogenesis: replicates in hematopoietic & endothelial cells & cause degenerative & necrotic changes • Clinical Feature: lameness (coronitis), cyanosis of tongue, morbidity 80%, mortality 50%, hydraencephaly & porencephaly in sheep, cattle have oral lesions like FMD & may be reservoirs • Vx: MLV against serotypes 10, 11, 17 in US (types 2, 13 not seen) • DDX? FMD in cattle
African Horse Sickness (AHS) • E • Etiologic Agent: Equine orbivirus, 9 serotypes • Host: horses, donkeys, mules, dogs that eat infected horse meat • Distribution: endemic in Africa, outbreaks in Middle East, N Africa, Spain, Portugal, Indai, never in Western hemisphere • Transmission: Culicoides spp. vectors • Pathogenesis: replicates in endothelium causing 1º and 2º viremia • Clinical Feature: pulmonary/acute form mortality 95% = frothy nasal discharge, cardiac/subacute form mortality 50-70% = edema, also mild form, Notifiable Dz • Vx: MLV in endemic areas, 60-day quarantine on horses entering US from Africa or other areas • DDX?
Genus Rotavirus • E • Etiologic Agent: domestic animals = serogroup A • Host: neonated of domestic animals and birds and humans • Distribution: worldwide • Transmission: ingestion • Pathogenesis: infect mature enterocytes & cause villus atrophy, self-limiting infection • Clinical Feature: morbidity 100%, mortality 0-50% • Vx: no carrier starte, inactivated vx given to dams to promote high levels of ab’s in the colostrum & milk • DDX?
Viral Arthritis & Tenosynovitis • E • Etiologic Agent: avian orthoreoviruses (11 serotypes) • Host: mainly broilers, also in layers & turkeys • Distribution: • Transmission: fecal-oral, low level of transolvarial transmission • Pathogenesis: • Clinical Feature: morbidity 100%, mortality <2%, birds sit on their hocks with swollen joints • Vx: Vx breeders so progeny have passive immunity • DDX?
Family Coronaviridae • Always a carrier state • Large club-shaped peplomeres • No inclusion bodies • Neutralizing ab’s against S and HE proteins • S protein=glycoprotein peplomere • HE protein=hemagglutinin-esterase in group 2 coronaviruses & toroviruses • M & E=transmembrane proteins, N=nucleoprotein • Group 1 Coronaviruses (mammalian) related & cross-protect • Group 2 Coronaviruses (mammal & avian) unrelated & no cross-protection
Transmissible Gastroenteritis of Swine (TGE) • E • Etiologic Agent: porcine coronavirus (related to canine & feline coronaviruses) • Host: swine, also dogs & cats can become infected, also starlings • Distribution: worldwide • Transmission: fecal-oral, mechanical, chronic carrier pigs shed ~10 wks, morbidity = 100% • Pathogenesis: destroys villous enterocytes of small intestine -> villous atrophy -> watery diarrhea • Clinical Feature: Epidemic TGE = new infection, mortality <2 wks age = 100%, Endemic TGE = motalitly =10-20% • Vx: attenuated vx given 3 wks prior to farrowing, virulent virus can be given to pregnant sows since no viremia • DDX?
Feline Infectious Peritonitis (FIP) • E • Etiologic Agent: Feline coronavirus (FCoV) [feline enteric coronavirus (FeCV) and feline infectious peritonitis virus (FIPV)] • Host: domestic & wild cats • Distribution: worldwide • Transmission: shed in feces, urine, saliva, aerosol, in utero • Pathogenesis: in vivo mutation of FeCV into FIPV in S glycoprotein to infect monocytes & macrophages, multiple pyogranulomatous lesions=pathognomonic, mortality ~100%, AB’s not protective, Dz depends on CMI response, very high serum titers! • Clinical Feature: classic/wet form=75% of cases, no CMI response, type 3 hypersensitivity, leakage of plasma proteins & fluid into body cavities, distended abdomen, Noneffusive/dry=25% of cases, due to partially protective CMI response, protracted course • Vx: MLV intranasally to elicit CMI with low AB formation
Bovine Coronavirus Enteritis • E • Etiologic Agent: bovine coronavirus • Host: cattle • Distribution: • Transmission: fecal-oral, inapparent persistent carriers • Pathogenesis: diarrhea more severe than rotavirus, multiplies in small & large intestines & destroys absorptive epithelium • Clinical Feature: morbidity 100%, mortality 0-50%, commonly in calves 1-4 wks of age • Vx: Vx dam to elevate AB levels in colostrum • DDX? Rotavirus
Enephalitis-Vomiting and Wasting Disease Complex of Swine • E • Etiologic Agent: hemagglutinating encephalomyelitis virus (HEV) • Host: piglets <4wks old • Distribution: N.A., Europe, Australia • Transmission: aerosols, ingestion • Pathogenesis: replicates in mucosa, spreads to CNS via peripheral nerves, no viremia • Clinical Feature: mostly subclinical, peracute/acute form morbidity & mortality ~100% in pigs <2 wks, vomiting & wasting disease (VWD) in pigs <4wks has a longer dz course but mortality still ~100%, diagnose via hemagglutination inhibition test • Vx: No, rely on endemic exposure • DDX? Psuedorabies
Avian Infectious Bronchitis Syn: “Gasping Disease” • E • Etiologic Agent: avian coronavirus, 8 serotypes • Host: chickens • Distribution: worldwise • Transmission: aerosols, ingestion, can have short carrier state • Pathogenesis: replicates in respiratory tract, then viremia, can damage L (only) oviduct, nephropathogenic strains = enlaged kidneys • Clinical Feature: young chicks morality 25-75%, layers form misshaped eggs that are not usable = “internal layers”, embryonated eggs will be dwarfed • Vx: Yes • DDX?
Family Togaviridae • No inclusion bodies • Not very stable in environment • Genus Alphavirus = horses & humans, biological mosquito transmission, not contagious • Genus Rubivirus = humans (German measles)
Western, Eastern, & Venezuelan Equine Encephalitis • E • Etiologic Agent: equine alphaviruses • Host: horses & humans • Distribution: all only in Americas • Transmission: biological mosquito trans. • Pathogenesis: maintained in endemic cycle of birds, epidemic strain arises from mutaion of endemic strain • Clinical Feature: WEE least virulent, fatality 20-40%, Highlands J related to WEE, EEE 90% fatality, VEE virulent = subtype 1ABC • Vx: bivalent or trivalent inactivated vx, also attenuated vx for VEE • DDX?
Family Flaviviridae • Enveloped, eicosahedral • Do not form inclusion bodies • Not stable in the environment • Used to be part of Togaviridae • Human Yellow Fever fist named = Flavi
Bovine Viral Diarrhea-Mucosal Disease Syn: BVD-MD • E • Etiologic Agent: Bovine Pestivirus, Cytopathic & Noncytopathic (mutates into the cytopathic) • Host: Cattle (beef & dairy), also sheep, goats, bison, other ruminants & swing • Distribution: worldwide • Transmission: highly contagious, cattle with persistent infection = reservoir, ingestion, fomites, transplacental, inhalation • Pathogenesis: replicates in GI & Respiratory, ulcers causing vesicular syndrome, immunosuppression • Clinical Feature: MD portion is what makes dz deadly, mortality 100%, persistent infections in calves & Mucosal disease • Vx: attenuated & inactivated vx • DDX?
Hog Cholera Syn: Swine Fever (NOT African Swine Fever) • E • Etiologic Agent: Porcine Pestivirus • Host: Pigs, most important $ dz of pigs worldwide • Distribution: endemic in Asia, Africa, Central & South America • Transmission: can survive in frozen pork for years, ingested or inhaled • Pathogenesis: replicates in tonsils & lymph nodes, viremia follows • Clinical Feature: peracute=young swine die w/o clinical signs, acute moralitly ~100%, subacute-chronic=low to moderate virulence, SMEDI, survivors can have lifelong infection, Reportable Dz • Vx: attenuated live in endemic areas, quarantine in outbreaks, test & slaughter in areas without disease • DDX? African Swine Fever, Hog Cholera does not hemagglutinate
Border Disease Syn: Hairy Shakers, Fuzzies • E • Etiologic Agent: ovine pestivirus • Host: lambs, disease of the fetus/kids, not adults • Distribution: worldwide • Transmission: contact w/fluids & body secretions, vertical trans. only • Pathogenesis: lambs are longterm carries & continually shed virus • Clinical Feature: CNS disease causing improper formation of myeling & neurologic signs, haircoat is hair instead of wool • Vx: none • DDX?
Louping Ill Syn: Ovine Encephalomyelitis • E • Etiologic Agent: Flavivirus • Host: mostly sheep, sometimes goats, horses, cattle, dogs, pigs • Distribution: only in Europe • Transmission: biologically via Ixodid ticks • Pathogenesis: goose-stepping, 2nd dz peak = CNS signs, • Clinical Feature: mortality 60% • Vx: Inactivated vx • DDX?