Virsus + Derm Flashcards
(36 cards)
Vesicular diseases
Vesicular stomatitis
• Foot and mouth disease
• Vesicular exanthema of swine*
• Swine vesicular disease*
• Senecavirus*
*pigs only
All diseases are reportable to state vet
Proliferative dermatitis
Pox/Parapox viruses
• Papilloma viruses
• Canine distemper virus
Vesicular stomatitis virus
Infects epithelium of ALL mammals - zoonotic
Mucosal vesicle & ulcers, udder & coronary band
Mimics other vesicular disease = reportable
Transmission of VSV
By sand flies, black flies, or direct contact
Common in horses, cattle, pigs
**horses don’t get foot mouth - differential
Pathogenesis of VSV
Infects epithelium = cytolytic effects
Spreads to draining lymph nodes
Host immunity determines if it spreads systemically
Foot & mouth disease
Foreign HIGHLY contagious animal disease
Aphtovirus - small ssRNA virus, non - enveloped
7 distinct serotypes
Endemic serotypes in Africa
SAT1, 2, 3
The rest are Asian
Transmission of FMD
Strict biosecurity is necessary
In semen and milk - cattle are more likely infected
Direct or indirect contact - fomites, animal movement, contamination of animal products, feeding uncooked garbage - swill
Pathogenesis of FMD
Primary infection - inhalation, ingestion, insemination of infectious particles
Viremia
Secondary replication in epi of mouth, muscle, teats, feet & areas of damaged skin
Shedding and findings of FMD
Sheds in secretion before onset of clin signs
Persistent in oropharynx
Young calves get myocardial inflammation
Clinical signs of FMD
Signs are most severe in cattle and swine
Fever, anorexia, salivation, vesicles in mouth, feet, teat, udders
Lesion progression of FMD
Fresh vesicles can occur within 24-48hr
Granulation tissue forms in 4-5 days
Healing after 7 days
Ballooning degeneration of stratum spinosum without breaching basal layer
DX of FMD
REPORT
Samples - vesicular fluid, epi flaps, oropharyngeal fluid/throat swabs
DX tests
Real time PCR in labs
PCR - 4hr
ELISA - 6hr
Virus isolation 3d X 2cycles = 1 week
Sequencing
Prophylaxis and control of FMD
Countries w endemic disease: vaccinate/slaughter
FMD free countries: test/slaughter, vaccinate - kill: vaccinate control zone, slaughter all vaccinated after outbreak is controlled
Vaccinate - live: vaccinate control zone, slaughter sick
Regain FMD free status
Stamping out - no vaccine is used
Vaccine to kill - 3m after slaughter of last vax animal
Vaccine to live - FMD free w vax, 12 m post vax or outbreak
Viruses that cause epidermal proliferation
Canine distemper virus
Papilloma virus
Pox virus
CDV
Can present w hyperkeratosis of nose/foot
Replication in lymphoid tissue, spreads via blood, CSF to brain & epi cells
- intracytoplasmic & nuclear inclusions in epi
Papilloma virus
Canine, bovine, equine, ovine
Key concepts of papilloma virus
Non-enveloped, DNA viruses
• Double stranded DNA
• Replicate in the nucleus of the host cells
• Resistant to lipids, acids, and low heat
Infection/path of papilloma virus
Infect basal epithelial cells as a result of abrasions
• Infected cells proliferate and differentiate slowly
• Viral gene expression is limited to proliferation
• Viruses are released when infected epithelium is desquamated from the surface
Host specific papilloma virus
Host specific virus causes proliferative lesions or warts which can spontaneously regress - self limit due to development of immunity
Squamous papillomas or epi tissue is most common
Fibropapillomas of fibrous tissue is also common
Infects early in life
Bovine papillomas virus
Types 1 and 2 cause fibropapillomas in
young animals that spontaneously regress
• Type 3 causes fibropapillomas that persist
• Type 5 causes teat papillomas (look like grains of rice)
• Type 6 causes frond-like papillomas
• Types 7-10 cause teat papillomas
BPV associated tumors
BPV 4 - bovine alimentary papilloma carcinoma in GIT, esophagus and reticulum, can occur w eating bracken fern
BPV 2 + bracken fern - carcinoma in bladder, hemorrhage
