Bunyaviruses Flashcards
1
Q
Bunyaviruses - genome, structure, special properties, transmission cycles
A
- (-) or ambisense RNA (3 segments)
- Enveloped; glycoprotein spikes
- Arthropod-vertebrate-arthropod transmission cycles
- Hantaviruses - vertebrate to vertebrate transmission
- Vectors: mosquitoes, ticks, culicoides midges, or flies, or specific rodents
- Most give a transient inf of mammal, but lifelong inf of insect vector
2
Q
Rift Valley Fever
- Transmission
- Clinical signs
- Mortality rate in sheep vs lambs
- Recovery speed
- Long lasting immunity?
- Zoonotic?
A
- Mosquitoes transmit to sheep
- Inappetence
- Mucopurulent nasal discharge
- Bloody diarrhea
- Pregnant sheep abort
- Mortality 20-60% in adult sheep, 90% in lambs
- Recovery is rapid and immunity is long lasting
- Zoonotic
3
Q
Akabane Disease
- Clinical diseases caused
- Transmission and hosts
- Differentials
A
- arthrogryposis/hydranencephaly
- Culicoides and mosquitoes = vectors / affect sheep, goats, cows
- bovine fetuses die early in pregnancy
- arthrogryposis (rigid fixation of limbs) b/c loss of spinal motor neurons
- bovine fetuses die shortly after birth, or survivors will have sensory, motor, and optical nerve damage
- no maternal disease
- Differentials: blue tongue; BVD, border disease / clinical signs, serology, virus isolation
4
Q
Nairobi sheep disease
- Transmission and hosts
- Clinical signs
A
- Brown ear tick = vector, affects sheep and goats
- high fever, hemorrhagic enteritis, prostration, abortion in pregnant ewe
5
Q
Crimean-Congo hemorrhagic fever
- Transmission and hosts
- Zoonotic?
A
- Ticks = vectors, affects birds, sheep, goat, cattle
- zoonotic - humans have severe hemorrhagic disease; risk to slaughterhouse workers, ag workers, veterinarians
6
Q
Hantaviruses
- hosts
- shed in?
- Zoonotic?
A
- rodents: lifelong inapparent infections
- shed in urine, saliva, feces
- zoonotic: hemorrhagic fever, renal syndrome, hantavirus pulmonary syndrome
