Parvoviridae, Adenoviridae (Ex2) Flashcards
Parvoviridae General Features
morphology, genome, replication site
- non-enveloped icosahedral, small
- linear single stranded DNA
- replication in nucleus of dividing cells
Feline Panleukopenia
other names, etiology, host
- Feline Distemper, Infectious Enteritis
- Feline Parvovirus
- all felines
Transmission of Feline Panleukopenia
- oro-nasally by exposure to infected animals, feces, secretions, or fomites
- in-utero transmission
- mechanical by flies
Pathogenesis of Feline Panleukopenia
- replication in pharyngeal lymphoid tissue
- viremia (in actively dividing cells) to other organs
- leukopenia hallmark of disease
- destruction of all white blood cell elements
- thrombocytopenia
- DIC
Pathogenesis of Feline Panleukopenia (Enteritis form)
- virus damages replicating cells in crypts of intestinal mucosa
- adsorptive cells on villi are unaffected, but have no replacement when they are lost
Pathogenesis of Feline Panleukopenia (in-utero infection)
early infection: fetal death and reabsorption
- abortions
- mummified fetuses
late infection: kittens born with damage to neural tissues
Pathogenesis of Feline Panleukopenia (CNS infection)
- CNS, optic nerve, and retina are susceptible
- cerebellar damage most common
- cerebellar hypoplasia
Clinical Signs of Feline Panleukopenia
- fever, depression, anorexia, rough coat, vomiting, bloody diarrhea
- severe dehydration, hypothermia, sudden death due to bacterial infection, DIC
- queens may show infertility or abortions
- cerebellar hypoplasia and retinal degeneration in kittens
Canine Parvovirus 2 transmission
- oro-nasal exposure to feces
- in-utero infection
- fomites
Pathogenesis/Signs of Canine Parvovirus 2
- enteritis, panleukopenia: destruction of epithelium of intestinal crypts, no replacement for absorptive cells on villi
- myocarditis: from in-utero, myocardial necrosis with cardiomyopathy failure, sudden death
- neurological disease: cerebellar hypoplasia, hemorrhage
- cutaneous disease: ulcers
Diagnosis of Canine Parvovirus 2
- clinical signs
- fecal viral antigen testing using ELISA or immunochromatographic test kit
- PCR
- virus isolation
- Serology: not best method
Vaccination for Canine Parvovirus 2
- modified live vaccine at 6-8, 10-12, and 14-16 weeks, followed by booster 1 year later, and every 3 years
- inactivated vaccines in pregnant dogs or young puppies
Porcine Parvovirus transmission
- oro-nasal in the pregnant sow followed by transplacental
- venereal from infected semen
Porcine Parvovirus Pathogenesis
- viremia
- transplacental: not all fetus are infected at the same time
- sites of replication: mitotically active cells in fetal tissue, also other organs and cells
- endothelial damage in many organs
Clinical Signs of Porcine Parvovirus
- hallmark: increase in mummified fetuses
- abortions uncommon
- embryo/fetus (70): develop lesions, but survive
- adults are subclinical
- some piglets born immunotolerant and shed the virus
Diagnosis of Porcine Parvovirus
- FA staining of frozen sections of fetal tissues
- PCR
- ELISA, HA, or HI
Vaccination/Immunization against Porcine Parvovirus
- inactivated and live vaccines available
- vaccinate all susceptible breeding sticks twice
- gilts can be naturally infected by mingling with older breeding stock
Adenoviridae General Features
- non-enveloped, hexagonal shape
- penton capsomeres with fiber protrude from surface
- non-segmented, linear double stranded DNA
- replication in nucleus
- intranuclear inclusion bodies are formed
Adenoviridae Pathogenesis
- cause acute respiratory or gastroenteric disease, mostly subclinical
- penton and fiber proteins are toxic to cells
- immunosuppression
- latency in lymphoid tissues
- can be oncogenic: E1A and E1B
Describe the immunosuppression action of Adenoviridae
- inhibition of MHC class 1 antigen transport by E3
- inhibition of tumor necrosis factor induced apoptosis by E3
- blocking of interferon-induced protein kinase R-mediated inhibition of viral protein synthesis
- modulate antiviral inflammatory responses by inhibiting nuclear factor kB transcriptional activity
Infectious Canine Hepatitis
genus, etiology, host
- Mastadenovirus
- Canine adenovirus 1
- canids and bears
Transmission of Infectious Canine Hepatitis
- CAV-1 found in all secretions and excretions
- oro-nasal route
- contact with secretions/excretions of infected dogs, fomites, ectoparasites harboring CV-1
Sites of replication for Infectious Canine Hepatitis
- macrophages
- kpuffer cells
- hepatocytes
- vascular endothelium of different organs
- parenchymal cells of organs and tissues
What are the main target organs of Infectious Canine Hepatitis?
- liver
- kidneys
- spleen
- lungs
Pathology of liver in Infectious Canine Hepatitis
- swollen, mottle liver
- gall bladder edematous thickening
- cirrhosis of liver
- hepatic fibrosis
Describe the ocular lesions of Infectious Canine Hepatitis
- blue eye
- damage to corneal epithelium
- uveitis
- corneal edema
Necrospy findings of Infectious Canine Hepatitis
- paint brush hemorrhage
- centrilobular necrosis of liver, with hepatocellular intranuclear inclusions
- grayish white foci in kidney cortex of recovered of chronic dogs
Canine Infectious Tracheobronchitis
other name, family, etiology
- Kennel cough
- mastadenovirus
- canine adenovirus 2
- bordetella bronchispetica
Canine Infectious Tracheobronchitis transmission
- highly contagious
- aerosolized droplets
- stress increases severity
Clinical Signs of Canine Infectious Tracheobronchitis
- harsh, dry coughing causing honking sounds
- rhinitis, serous nasal discharge
- conjunctivitis
- severe pneumonia
Treatment of Canine Infectious Tracheobronchitis
- antitussives (cough suppressants) with bronchodilators
