Coronaviruses Flashcards
Viral Resp Diseases V
Structure ?
(+) ssRNA
4 genuses - alpha, beta, gamma, delta
large !!
large club-shaped spikes make spike protein (S) which is the major target for the antibody respond
Lesions associated with coronaviruses in the respiratory form
in the upper airways = neutrophilic and lymphocytic infiltrate, sloughing epithelial cells, loss of cilia, hypertrophy of mucosal glands
in the lungs = haemorrhages with infiltrate, severe oedema, epithelial cell detachment, fibrinous exudate
Lesions in the enteric form
in the SI = villous necrosis, atrophy, microabscesses, haemorrhage, villous blunting and fusion
Name the most important alphacoronaviruses
transmissible gastroenteritis virus (TGE)
porcine respiratory coronavirus (PRC)
feline enteric coronavirus
feline infectious preitonitis
Name the most important betacoronavirus
bat coronavirus HKU4
Name the most important gammacoronavirus
infectious bronchitis virus in chickens
TGE overview
piglets - vomiting, watery diarrhoea, weight loss
adults asymptomatic
destruction of enterocytes leading to malabsorption
oral vaccines not effective
coronavirus diagnosis ?
impression smears with IHC staining and microscopy
ELISA
PCR
PRC overview
TGEV –> mutation in spike protein –> PRC
Feline enteric coronavirus overview
faeco-oral transmission
infects intestinal mucosa
CS are mild and self-limiting
Feline Infectious Peritonitis overview
infects macrophages, leading to a multisysmteic disease
may be “wet form” (effusion), “dry form” (granulomatous) or “mixed”
CS : pyrexia, weight loss, icterus, thoracic effusion (dyspnea, tachypnea, open mouth breathing, cyanotic MMs, muffled heart sounds), ocular changes, neuro signs, abdominal swelling and masses, enlarged LNs, histological changes (pyogranulomatous foci seen as fibrinous plaques on serosal surface
supportive treatment used due to low survival rate
infectious bronchitis virus overview
chickens
CS : resp signs, conjunctivitis, dyspnea, facial swelling, depression, huddling, feed consumption, increased water intake, death
live attentuated vaccines available given by a spray or in drinking water
