arteriviridae
TRANSCRIPT
arteriviridae
GASCON, ANGELICA C.LARGADO, JESSICA C.LEUTERIO, RAMON E.SALINAS, KRIZZELLE ALIZZA S.SUMELDAN, JODEN OLIVER D.
arterivirus
•Derived from Equine Areteritis virus
Virion and nucleic acid properties
•Spherical virions •50-70 nm in diameter•Enveloped •Linear positive sense•Single-stranded RNA•13-15 kb in size•Infectious genomic RNA
Virion and nucleic acid properties
•Single nucleocapsid protein-N• 6 enveloped proteins-E,GP2,GP3,GP4GP5,M
Virion and nucleic acid properties
•Large enveloped gycoprotein
Virion and nucleic acid properties
taxonomyOrder: Nidovirales Family: ArteriviridaeGenus: ArterivirusSpecies: Equine Arterivirus
Lactate Dehydrogenase Elevating virusPorcine Reproductive and
Respiratory Syndrome Virus
replication
•Replicate mostly in macrophages•Very minimal in other cell types•Host range is highly restricted•Can subvert protective host innate immune responses•Apoptosis•IFN signaling pathways
replication
•Receptors for PRRS1. CD1632.Sialoadhesin3. Heparin Sulfate
Glycosaminoglycans
replicationCYTOPLASMIC•Attachment to hostreceptors mediates clathrin-mediated endocytosis of the virus into the host cell.
replication•Fusion of virus membrane with the endosomal membrane.•ssRNA(+) genome is released into the cytoplasm.
replication•Synthesis and proteolysis of replicase polyproteins.•Replication occurs in viral factories. •A dsRNA genome is synthesized from the genomic ssRNA(+).
replication•dsRNA genome is transcribed thereby proiding ssRNA(+) genomes.•Synthesis of structural proteins encoded by subgenomic mRNAs.
replication•Assembly and budding at the membranes of ER, intermediate compartments, and/or Golgi complex.•Release of new virions.
diseases
1. Equine Viral Arteritis2. Porcine Reproductie and
Respiratory Syndrome3. Lactate Dehydrogenase
Elevating Disease4. Simian Hemorrhagic Fever
Equine viral arteritis
PINK EYE
Equine viral arteritis
SCROTAL EDEMA
Porcine Reproductive
and respiratory syndrome
prrs
•1st designated as “mystery swine disease”•“lelystad virus”-Netherland•Causative virus first appeared-US, Asia, Europe
prrs
•Infects only domestic and wild pigs•initially characterized by•Anorexia•Fever •Lethargy
prrs•Affected animals:•Dyspnea/ hyperpnea•Transient hyperemia•Cyanosis of the extremities
prrs
CLINICAL SIGNS
prrsSows
Dry sows-first month of infection•Short periods of inappetence•The body temperature may be elevated
prrs
Sows
•Transient discoloration (blueing) of the ears•Premature births
prrs
Sows•Sows in late gestation•Abortion•Premature births•Stillbirths•Mummified fetuses
prrs
prrs
stillbirth Mummified fetuses
prrs
Piglets•More diarrhoea.•Less viable piglets.•Increase in respiratory infections
prrs
Diarrhea in infected piglets
prrsWeaners & Growers
•Period of slight inappetence.•Mild coughing.•Hairy wasting pigs.•In some herds there are no symptoms.
prrs
weakness Rough hair coat
prrs
Boars•Inappetence•Increased body temperature•Lethargy•Loss of libido•Lowered fertility•Poor litter sizes•Lowered sperm output
prrsCauses / Contributing factors•Droplet contamination•Nasal secretions, saliva, feces and urine•Permanently populated houses•Movement of carrier pigs.
prrs•Airborne transmission•Mechanical means via faeces, dust, droplets and contaminated equipment, etc.•Contaminated boots and clothing.•Vehicles.•Artificial insemination
Causes / Contributing factors
prrs•Mortality is high
TRANSMISSION•Direct contact•Through secretions•Excretions•Transplacental transmission
prrsPATHOGENESIS• virus replicates in the macrophages of the lungs, lymphoid tissue and endothelial cells•Viremia-24 hours
prrsLesions of acute infection•Lymph node enlargement •Intestinal pneumonia
prrsDISEASES
CAUSATIVE
AGENT
SAMPLE/S DIAGNOSTIC TEST
EQUINE VIRAL
ARTERITIS
EQUINE ARTERIVIRUS
NASOPHARYNGEAL SWABS, BLOOD
PLACENTAL TISSUES AND FLUIDS FROM FETAL LUNG,
LIVER, LYMPHORECTICULAR
TISSUES
RT-PCR
IMMUNOHISTOCHEMICAL TESTING
PORCINE REPRODUC
TIE AND RESPIRATO
RY SYNDROM
E
PORCINE REPRODUCTIE
AND RESPIRATORY SYNDROME
VIRUS
TISSUES
BLOOD
HISTOCHEMICAL STAINING
SEROLOGICAL EXAMINATION
LACTATE DEHYDROGENASE
ELEVATNG DISEASE
LACTATE DEHYDROGENASE ELEVATNG
VIRUS
BLOOD SEROLOGICAL EXAMINATION
SIMIAN HEMORRH
AGIC FEVER
SIMIAN HEMORRHAGIC FEVER VIRUS
WHOLE BLOOD REVERSE TRANSCRIPTION
COUPLED REAL TIME POLYMERASE CHAIN
REACTION
prrs
IMMUNITY, PREVENTION AND CONTROL
•Infected pigs are immune to reinfection•Vaccination-live attenuated, inactivated•limit the frequency of seed stock introductions to the sow herd•assure that the replacement gilts be well-acclimatized to the PRRS virus
prrs
IMMUNITY, PREVENTION AND CONTROL
•Boars introduced into negative herds should be quarantined for 60-90 days after purchase and confirmed negative serologically
prrs
IMMUNITY, PREVENTION AND CONTROL
•depopulate, clean and disinfect the facilities and, after a few weeks, repopulate with stock free of PRRS
prrs
IMMUNITY, PREVENTION AND CONTROL
•Control is by exclusion•no specific treatment •Broad-spectrum antibiotics. •Anti-inflammatory products (e.g. aspirin)
prrs
IMMUNITY, PREVENTION AND CONTROL
• Other helpful techniques • Early weaning and isolation of piglets•Regular serologic monitoring• Testing (ELISA, PCR and IFA) •Removal of persistent carriers in herds•improving biosecurity.
THE END