330 likes | 577 Views
The integument ’s viral diseases in horses. 1. Papillomatosis Cattle type 1 , 2 and horse papilloma virus sarcoid: bpv1 enhanced lcr activity in horse cells (long control region) Pathogenesis : Virus str germinat. cell proliferation,
E N D
The integument’s viral diseases in horses 1. Papillomatosis Cattle type 1, 2 and horse papilloma virus sarcoid: bpv1 enhanced lcr activity in horse cells (long control region) Pathogenesis: Virus str germinat. cell proliferation, but ceratinocytes contain the matured viruses Clinical signs: 4-6 weeks cauliflower like, warted, benign cell tumours: exception; sarcoidbovine papillomav. type specific protection Diagnosis: Macroscopic: signs are characteristic Histology: ELMI, IF, PCR AGID (indirect)
Differential diagnosis: Epithelial and connective tissue tumours Strangles Str. Equi (2) abscessi Glanders P. mallei granulomas in skins, erosions in nasal cavity, respiratory signs Dermatophylosis D. congolensis scurf Lymphangitis caused by Coryneb. Pseudotuberculosis lymphangitis Histoplasmosis (Histoplasma farciminosum) lymphangitis
Papillomas caused by equine papillomavirus Photo; R. Pascoe Sarcoid caused by bovine papilloma virus
2. Coital exanthema Alpha herpesvirus, EHV-3, strictly species specific, world-wide spread Pathogenesis: Venereal spread (sometimes on the udder) mucous membrane of vagina, glans local multiplication papulae epithel degeneracy erosions scurf pigmented spots prone to recovery Diagnosis: Virus isolation, PCR Differential diagnosis: Due to its characteristic clinical signs and predilection’s sites can not be confused with other diseases
Photo; T. Lane Lesions due to coital exanthema virus
3. Vesicular stomatitis Rhabdoviridae, vesiculovirus, 2 serotypes: Indiana New-Jersey Only on the American continent, transmission by insects, horses, ruminants, pigs, humans Clinical signs: Vesiculae on the mucous membrane of the oral cavity, on the skin, cushion, udder. Morbidity 10-15%, Mortality 0% Diagnosis: direct: virusisolation cell culture VERO, BHK-21, giant cell formation, embr. egg, CF, IF, IS-ELISA mouse inoculation indirect: CF, VNT, ELISA Differential diagnosis:The only vesicular disease of horses ruminants, pigs: FMD, SVD, VES, Stomatitis papulosa
Photo: B. Wright Slobbers, due to vesicles in oral cavity Erosions on the joint
Viral infectious diseases of the blood circulatory- and lymphatic system African horse sickness Arthropode borne = arbovirus infection in equidae (Culicoidae) Reoviridae, Orbivirus 10 serotypes, varying virulence Mosquitoes spread (real vector) warm, wet climate, over 500 m does not exist Pathogenesis: mosquito skin 5-9 days incubation lymph.n. (5-10 days) viraemia vascular endothel cell degeneration vasculituis thrombosis oedema, haemorrhages lung and heart insufficiency perishing 3-5 d.PI Clinical signs: Mortality 50-90% peracute: frothy nasal discharge, 41°C fever subacute: haemorrhages, oedema in connect. tiss. andsublingual, fever
Diagnosis: clinical signs, pathol. findings (fibrin, oedema) labordiagn. direct: Virus isolation: Cef, mouse i.c. a.g. detection from leucocytes: ELISA, IF nucleic acid detection: RT-PCR indirect: CF, AGID, ELISA Differential diagnosis: (Oedema, haemorrhage) Equine arteritis abortion, virus isolation, PCR Equine infectious anaemia: lymphoid cell prolif spleen, interstitial lymphocytic infiltration of liver Coggins test Anthrax dark blood, carbunculus,splenomegalia bacter and(Ascoli test) Babesiosis haemocytological findings
Photo; J. Hodgson Large amount of froth in peracut stage Photo; A. Elmissery Subacut oedematous swelling
Equine infectious anaemia world-wide spread, Retroviridae, Lentivirus genus Epizootology: lifelong carrier horses, arbovirus, short term carrier vector Pathogenesis: Insects(Tabanidae,Stomoxys c.)viraemialymphoret. tiss; lymph.n., liver, spleen, bone marrow 2-3 weeks fever anaemia, decreased rbc production increasing rbc lysis immune complexes new antigen variant repeated viraemic fever immune supression immune complex formation Clinical signs: acute; haemorrhages, oedema chronic; recurrent fever, fatigue Pathological findings: anaemia Sago palm like spleen: lymphoid cell proliferation, mace like liver: limphohistiocytic infiltration pale kidneys: glomerulonephritis
Diagnosis: haematology histopathology isolation from leucocytes on leucocyte cell culture nucleic acid detection: RT-PCR indirect: Coggins test (AGP), ELISA Differential diagnosis: African horse sickness acute phase: frothy nasal disch Equine arteritis abortionand respiratory dis. Anthrax carbunculus, Ascoli test Babesiosis blood smear Equine encephalitis cl. signs of the nervous system Petechiae on the mucous membrane Photo; T. Lane
Viral infectious diseases of the respiratory tract Herpesviruses: Equine abortion; EHV-1 World-wide spread, Alphaherpesvirinae, varicellovirus Pathogenesis: Aerogen (peroral) nasopharyngeal muc. membrane blood-stream leucocytes lung bronchopneumonia uterus foetus lung, liver abortion nervous system inflammation of the arterioli degeneration of the nerve-cells paralysis of hind limbs, incoordination latency Diagnosis: direct: virus isolation, IF, IHC, PCR indirect: VN
Differential diagnosis: Respiratory, nervous s. forms, abortion Rhinopneumonitis (EHV-4) mouse pathogenicity, abortion rare, IF Mab, PCR foals EHV-2 in the first 3 month foals EHV-5 between 3-9 month adenovirus between 2-4 month diarrhoea (immune deficient Arabian thor.br.) Reovirus foals Aphtho,-Erbovirus acute, febrile resp.disease, RT-PCR Equine arteritis abortion, carrier stallion Influenza virus acute, febrile resp. diseas. e.egg inoc HAI, RT-PCR Paramyxoviruses only in Far-East and Australia Rabies altered behaviour, Negri bodies IF Equine encephalit. seasonal, human diseas. too e.egg.in Bornavirus endemic, epileptiform convulsions
Foals’ respiratory disease caused by EHV-2 World-wide spread, pathologically contentious importance Gammaherpesvirinae, endemic, latency Pathogenesis: dust aerogen lung, alv. macrophage epithel c. degeneration entry for Rhodococcus. equi Diagnosis: from leucocytes cocultivation virus isolation, from nasal discharge virus isolation, PCR Differential diagnosis: EHV-5 between 3-9 month Adenovirus between 2-4 month diarrhoea (immune deficient Arabian thor.br.) Reovirus foals Aphtho-,Erbovirus acute, febrile resp.diseas. RT-PCR Influenza virus acute, febrile resp.diseas. e.egg in. HAI, RT-PCR, high morbidity
Rhinopneumonitis caused by EHV-4 World-wide spread, Alphaherpesvirinae, Varicellov. endemic Pathogenesis is the same like EHV-1 its virus variant pneumotrop Diagnosis: Like in the case of EHV-1, mouse pathogenicity index Differential diagnosis: see EHV-1 Foals’ respiratory disease caused by EHV-5 lesser-known, endemic, Gammaherpesvirinae, Rhadinovirus genus, between 3-9 month manifest itself Differential diagnosis: like EHV-2
Adenovirus Arabian thoroughbred frequent: combined immune deficiency (CID) autosomal recessive transmittance lack of functional T és B lymphocytes secondary bacterial infection Aphtho- and Erboviruses 3 serotypes (1, 2, 3) in young horses (2 years) Serotype 1 related with FMDV, fever, nasal discharge, cough, sore throat. Diagnosis: direct: virus isolation (serotype 1 broad cell spectrum) indirect: CF, VNT Differential diagnosis: Adenovirus diarrhoea too, between 2-4 month Reovirus foals Herpesviruses see. herpes Equine influenza embr.egg propagation, HAI, RT-PCR
Respiratory disease caused by Reovirus 3 serotypes orthoreo 1, 2, 3, non species specific, in early age, pneumoenteritis, bact. coo-infection Diagnosis: direct: virus isolation, HA, RT-PCR indirect: HAI, VNT Differential diagnosis: Adenoviruses Herpesviruses Aphtho- and Erboviruses Equine influenza viruses
Equine influenza World-wide spread, Orthomyxoviridae, Influenzavirus2 types: H7N7 (Prague) H3N8 (Miami)more severe form Susceptible horses~100% diseased, but quick recovery Pathogenesis: Aerogen infection nasal muc.membrane viraemia lung bact. complication Clinical signs: Fever, respiratory symptoms, decline, inappetance Diagnosis: direct: Virus isolation ine.egg, HA, IF, a.g. ELISA, RT-PCR indirect: HAI
Differential diagnosis: epizootiology, clinical signs, Herpesviruses lower morbidity, abortions Adeno-, } Aphtho-, Erboviruses } lower morbidity, age Reoviruses } Equine arteritis abortions, oedema,haemorrhages Bacteria: Streptococcusespustules, abscesses Rhodococcus equi lung abscesses
Viral infectious diseases of digestive tract of horses Diarrhoea caused by Rotavirus Young foals, in their first some weeks, lack of hygiene, A-G groups, all animal pathogens, most prevalent; A, nsp4 enterotoxin like effect Clinical signs: diarrhoea, inappetance, exiccosis Diagnosis: direct: virus isol. difficult, IF, ELMI, SDS-PAGE, RT-PCR CIEF out-dated false positivity indirect: CIEF, VNT Differential diagnosis: Toroviruses infect in all life
Diarrhoea caused by Toroviruses Nidovirales, coronaviridae, torovirus genus Horse, ruminant, pig, cat, human, clinical signs are infrequent, stenoxen Diagnosis: direct: virus isolation, RT-PCR indirect: ELISA Differential diagnosis: Rotavirus young age, higher morbidity
Viral infectious diseases of the reproductive organs Equine abortion (see at respiratory viral diseases) Equine arteritis World-wide spread, 1 serotype, different virulence, virus carrier stallions, abortions Pathogenesis: Aerogen-peroral infection macrophages viraemia damage of the arteoli in all body abortion Venereal infection muc.memb reg.lymph.n. viraemia … Clinical signs: Mainly inapparent, but could be acute and chronic (stallion), fever, resp. signs, oedema, gravid mares abortions Diagnosis: direct: Virus isolation, IF, IHC, RT-PCR indirect: VNT, ELISA
Differential diagnosis: 1. Respiratory signs: Herpesviruses Equine influenza Adeno-, Reo-, Aphto-, Erboviruses bacteria: Rhodococcus, Malleus 2. Abortion: Abortion by EHV-1(more frequent, no oedema) bacterial abortions: Staphylo-, Streptococcus E. coli, Klebsiella Salmonella abortusequi Taylorella equigen (Chronic equine metr.) Actinobacillus equli Leptospirae Chlamydophila psittaci 3. Oedema: Eq.infect.anaemia, Afr.horse sickness, Babesia pyosepticaemia
Viral Infectious diseases of the nervous system Rabies World-wide spread, Rhabdoviridae, Lyssavirus genus 5 genotypes 4;bats! 1; foxes sylvatic form Pathogenesis: bite muscle cells myoneural junction alongside neurones spinal chord brain change of behaviour brain nerve bundle paralysis Clinical signs: incubation 2-8 weeks, rabid (frantic) form quiet rabies excitation, colic, frequent urination, incurable Diagnosis: direct: IF, histology: Negri bodies, mice i.c. inoculation indirect: VNT, (FAVN, RFFIT)
Differential diagnosis: EHV-1 spinal chord paralysis, slowly progrediating Equine encephalitis vectors, seasonal, human cases as well Borna disease endemic Tetanustetanic, sawing-horse position, anamnesis Botulismsatonic paralysis, anamnesis
Equine encephalitis: Eastern (EEE), Western (WEE),Venezuelan (VEE): Togaviridae, Alphavirus genus Only in America, arboviruses, real vectors in spread, seasonal, rezervoir specieses: wild birds, (rodents), eurixen viruses: poultry, humans, high mortality! Clinical signs: Fever, hyperestesy, gnashing, hyperactivity Diagnosis: direct: virus isolation: mice i.c., e.egg, cell cult. indirect: CF, HAI, VN Differential diagnosis: Getah v. Flavivirus enceph: West Nile v. St Luis-, Japan enc. only labor. examin can be distingv. Rabies changed behaviour Borna disease Tetanus, Botulism
Flavivíruses caused encephalitis Flaviviridae, Flavivirus West-Nile virus All over the world Arbovirus – mosquitos, gnats birds, mammalians, humans Pathogenesis: Gnats viraemia organs neuroinvasive strains - encephalitis Clinical signs: 2-4 weeks incubation period incoordination,excitation, colic Diagnosis: direct: isolation, IHC, RT-PCR indirect: VN, IgM ELISA, IF
Differential diagnosis: EHV-1 : myelitis paralysis, slow progrediation Rabies: behavioural change, labor EEE, WEE, VEE: epidemiol., labor. exam. Borna disease: localization, labor. exam. Tetanus Botulism
Borna disease ELMI examination always negative, endemic, seropositivity In other countries, horse, sheep, goat, cat, human, Bornaviridae, Bornavirus genus, reservoir: shrew (Sorex…) Pathogenesis: Grazing aerogen spread n. olfactorius brain, nerve-cells slow degeneration in the presence of antibodies Incubation period 2 weeks with 90% lethality in horses Clinical signs: digestive- and respiratory tract’s disorders, Excitation, depression, salivation, apathy, spasmus slowly progrediating poliomyelitis In sheep "falling down" is characteristic Diagnosis: direct: virus isolation cell culture, IHC, RT-PCR indirect: Westernblott, ELISA
Differential diagnosis: EHV-1 prone to cure Rabies behaviour, IF, Negri Equine encephalitis seasonality Tetanus Botulism