Herpesviridae pt 3 Flashcards
what subfamily??
speed of replication?
assoc. w what type of infections?
infected cells are?
maintained in latent form in where?
- BETAHERPESVIRINAE
-slowly replicating viruses
-assoc. with chronic infections
-infected cells are enlarged (cytomegaly)
-maintained in latent form in secretory glands (salivary) and lymphoreticular cells (macrophage, lymphocytes)
-assoc. with continuous viral excretion
what disease in this subfam
caused by what virus
host
transmission
-inclusion body rhinitis
-caused by porcine herpesvirus 2 aka porcine cytomegalovirus (PCMV)
-pigs, severe in piglets
-transmit via inhalation, maybe transplacental
inclusion body rhinitis
-pathogenesis
-primary site of replication
-widespread petechiae and edema, most common in thoracic cavity and subQ tissue
-primary site of rep: nasal mucous glands, epithelial cells of URT –> stillbirth, mummification, neonatal death, endothelial cell damage and necrosis: petehcial hemmorrhage and edema, in neonates: bone marrow damage and anemia
inclusion body rhinitis - what do infected cells look like
infected cells are enlarged and possess intranuclear inclusion bodies especially in nasal glands.
inclusion body rhinitis CS
-<3 weeks old: mucopurulent rhinitis, infected neonatal pigs appear weak, anemic or stunted and there may be edema around throat or tarsal joints
-fetal mummification, still births, neonatal death, failure of piglets to thrive assoc. with infection of pregnant sow
-subclinical disease in adults
sub fam gammaherpesvirinae
-where do they replicate
-cause death without ??
-latency occurs in what tissues
-some cause ???
-replicate in lymphocytes
-slowly cytopathic for epithelial and fibroblastic cells, causing death without virion production
-some continously shed from epithelial surfaces
-latency occurs in lymphoid tissues
-some cause lymphoid tumors
what virus in gammaherpes and what are synonoyms?
malignant catarrhal fever (MCF)
aka bovine malignant catarrh, malignant head catarrh
Malignant catarrhal fever
-host
2 most important
highly fatal in cattle and some wild ruminants
-at least 10 MCF viruses recognized
1. Alcelaphine herpesvirus 1 - causes wildebeest associated MCF
2. ovine herpesvirus 2 - causes sheep associated MCF
MCF - wildebeest associated MCF
-transmitted
-occurs in what country?
-disease in principle host
-transmitted from wildebeest to cattle becuase they are intermingling
-AFRICA
-no disease in principle host (wildebeest)
-EPIZOOTIC AND SEASONAL
MCF- sheep assoc. MCF
-occurs where?
-transmitted?
-occurs worldwide
-transmitt. from sheep to cattle
-goats can be source of infection to cattle
-occurs year round in cattle, moderate increase during lambing season
-sporadic, ocasional outbreaks
MCF
-transmission between wildebeest vs. transmisstion to cattle
between wildebeest: horizontal and occasional intrauterine transmission in wildebeest, inapparent infection
-to cattle: AHV 1 present in nasal and ocular secretions of young wildebeest in a cell free state, ingestion of pasture contaminated with nasal or ocular secretions from young wildebeest, direct or dclose contact, inhalation of aerosols, direct or close contact with wildebeest during calving (virus in cell free state in young), virus in cell associated form in adult wildebeests, so rarely transmitted from adults
MCF
-transmission between sheep vs. to cattle
between sheep: respiratory, transplacental rare, contact with nasal secretions (INAPPARENT INFECTION IN SHEEP)
to cattle: NOT KNOWN, probs inhalation or ingestion
MCF
-transmisson from cattle to cattle?
-cattle are dead end hosts, no transmission between them, cattle have cell associated virus, NOT cell free virus in secretions
MCF
pathogens.
-necrotizing vasculitis
-vascular lesions accounts for development of gross lesions, such as epithelial erosions and keratoconojunctivits
MCF
CS (4 forms)
peracute form: sudden death
head and eye form: majority of cattle disease, erosions on tounge
alimentary/intestinal form: initially in head/eye form, but death occurs from severe diarrhea. diarrhea is rarely assoc. in wildebeest derived MCF, but is more common in sheep derived MCF, necropsy finding: ZEBRA STRIPING: severe longitudinal linear congestion of mucosa
-mild form: inoculated animals, recovery expected
