Viruses and vesicle formation Flashcards
(30 cards)
Define vesicle
circumscribed epidermal elevation in the skin containing clear fluid
usually less than 5mm indiameter
What is a bulla?
circumscribed epidermal elevation in the skin containing clear fluid
greater than 5mm
What is acantholysis?
death and loss of stratum spinosum cells -> clear fluid forms between overlying layers and stratum basale
What is an erosion?
partial loss of epidermis that does not penetrate beneath the basal laminar zone due to a bullar or vesicle bursting
What is an ulcer?
a loss of epidermis and dermis (and somtimes deeper tissue) due to a bulla or vesicle bursting
Name some vesicular diseases that cause oral lesions in farm animals and what species do they affect?
Foot and mouth disease (FMD) - cattle, sheep, pigs
Swine vesicular disease (SVD) - pig
Vesicular stomatitis (VS) - cattle, pigs, horses
Describe the features of Picornaviridae
virions are spherical, non enveloped
genome = single molecule os +ve sense RNA
replicates in the cytoplasm of host cells
What are the important genera of Picornaviridae and what diseases are included?
Apthovirus - FMD
Enterovirus - SVD
How is FMD (foot and mouth disease) transmitted?
respiratory infection
ingestion of contaminated food
direct inoculation
Clinical signs of FMD (foot and mouth disease)
Fever
Inappetance
Decreased milk production
Hypersalivation
vesicles on tongue, teats and feet (lameness)
abortion (due to fever)
What are the secondary consequences of oral vesicles in FMD (foot and mouth disease)?
oral vesicles rupture due to smacking of lips
-> large denuded ulcerative lesions
-> secondary bacterial infection
What samples are required for FMD (foot and mouth disease) diagnosis?
vesicular fluid
epithelial tissue from edge of vesicle
blood in anticoagulant
serum
pharyngeal fluid
What test is used to diagnose FMD (foot and mouth diseas)?
ELISA
PCR
How is FMD (foot and mouth disease) controlled
culling
quarantine and restricted movement
Clinical signs of SVD (swine vesicular disease)
fever
lameness due to lesions on coronary bands
How is SVD (swine vesicular disease) diagnosed?
ELISA or virus isolation
Control of SVD (swine vesicular disease)
culling
Describe the features of Rhabdoviridae and which disease belong to the family
single stranded
-ve sense
non-segmented RNA genome
red shaped
enveloped
Vesivular stomatitis virus
How does vesicular stomatitis enter the body?
through breaks in the mucosa and skin
minor abrasion
arthropod bites e.g., mosquito
Clinical signs of vesicular stomatitis
Fever
hypersalivation
lameness
vesicles
blisters on oral mucous membranes
vesicular lesions on teats, coronary bands, snout
How is vesicular stomatitis diagnosed?
immunofluorescent antibody staining of vesicle tissue
ELISA on vesicular fluid
PCR
Cell culture
Describe the genome of caliciviridae
single molecule of linear, +ve sense, ssRNA
Replicate in cytoplasm
What are the 2 main causes of cats with upper resp tract disease?
feline calicivirus
feline herpes virus
Clinical signs of FCV?
conjunctivitis
rhinitis
tracheitis
pneumonia
vesiculation and ulceration of oral epithelium
fever
lethargy
anorexia
stiff gait
