Arbo 1 Flashcards
Bunya Family includes what genuses
Bunyavirus
Hantavirus
Families of Arbovirus
Bunya
Flavi
Toga
Reo
Flavivirus serotypes
SLE
Dengue
Yellow Fever
JEE
West Nile
Hantavirus serotype
Sin Nombre
Bunyavirus serotypes
California + Lacrosse
Togaviridae genuses
Rubella
Alphavirus
Alphavirus serotypes
EEE, WEE, VEE
Reoviridae genus and Serotypes
Rotavirus
Coltivirus (Serotype = Colorado Tick Fever Virus)
Two types of transmission cycles
Man > Arthropod > Man
Animal > Arthropod > Man
Arbovirus that displays BOTH transmission cycle types
Yellow Fever
Arboviruses that have Animal-Arthropod-Man cycle:
Japanese Encephalitis
WEE, EEE
_Jungle _Yellow fever
Arboviruses that show Man-Arthropod-Man cycle
Dengue
Urban Yellow Fever
Most arboviruses have what host
mosquito
Which Arboviruses have tick host
Colorado Tick Fever
Other animal reservoirs
Birds (JE, SLE, EEE, WEE)
Pigs (JE)
Monkeys (YF)
Rodents (VEE, Hantavirus)
___ and ___ cause hemorrhagic fever
yellow fever, dengue
Dx for arboviruses
Serology (USUALLY)
Culture
Direct detection tests
Bunyavirus human disease:
LaCrosse Encephalitis
Bunyavirus genus that we’re concerned with
California Group (causes LaCrosse)
Bunyavirus structure
Enveloped Segmented (-)RNA
Helical capsid
Bunyavirus segments
L, M, S
Bunyavirus carries ____
Transcriptase
Most common cause of pediatric arboviral encephalitis
Bunyavirus
Arbovirus infects ______ system
Reticuloendothelial
_______ can block secondary viremia in arboviruses
Antibodies
Highest incidence of LaCrosse virus is in…
the midwest
(Ohioooooo)
Major reservoir of LaCrosse (Bunya)
Chipmunks + Squirrels
LaCrosse Serology: When does antibody titer increase?
Between the acute and convalescent phases
Lacrosse virus has not been….
isolated from CSF
CSF characteristics for LaCrosse infection
Normal-ish ICP
Normal Glucose
Mildly high Protein
PMN Pleocytosis
LaCrosse Encephalitis Brain biopsy can show…
Perivascular infiltration with Mononuclear Cells
Bunyavirus Control and Treatment
No Treatment or vaccine
Hantavirus: 2 clinical presentations-
- HPS = Hantavirus Pulmonary Syndrome (Sin Nombre)
- HFRS = Hemorrhagic Fever w Renal Syndrome*
*In Asia
HPS (Sin Nombre) characterized by a ____ followed by acute respiratory failure
febrile prodrome
HPS Symptom Stages
Early (flu like)
Late (Pulmonary)
HFRS initial symptoms
Head/Body ache
FEVER
Nausea
Inflammation/ Redness of eyes
Rash
HFRS Later Symptoms
Low BP
Shock
Vascular leakage
ARF
Hantavirus primarily targets ______ cells after dissemination
Vascular Endothelial
esp. in heart, lung, lymph
Hantavirus causes __________ because of increased capillary permeability
protein-rich edema
(and Interstitial Pneumonitis of edema fluid, mononuclear cells, and lymph/leukocytes)
Hantavirus reservoir
Deer Mouse
Humans get infected by Hantavirus by what 3 ways?
inhalation of rodent waste
rodent bite
contact with excretion of rodent
Hantavirus Dx
Serology IgM and IgG
Immunochemistry
RT-PCR
Hantavirus Tx
Supportive care (Fluid, BP, O2)
Flaviviruses hosts
Broad range
Flavivirus genome/structure
Positive ssRNA (resembles mRNA)
Icosahedral
Enveloped
Flavivirus replicates in the ______, and is released by ______
cytoplasm, exocytosis
Flavivirus two general types of diseases:
- Encephalitis (SLE, JE, West Nile)
- Hemorrhagic Fever (Dengue, Yellow Fever)
SLE incubation period
4-21 Days
SLE is a severe ____ disease that causes ________
neuroinvasive
encephalitis
SLE (Flavi) virus is produced (in body) in the ______, and then causes _______
Produced in site of innoculation,
causes primary viremia
SLE is cleared from system by ________
reticuloendothelial system
Secondary viremia during SLE leads to ________
invasion of CNS
After healing from SLE, __________ occurs
Spongiform changes
SLE CSF examination shows
mononuclear pleocytosis
Elevated protein
Normal Glucose
SLE lab Dx
Serum or CSF
to detect IgM and Antibodies
Japenese Encephalitis (JE) Stages
- Early - Fever, diarrhea, rigor (and reduced consciousness)
- Later - Flaccid paralysis and Parkinsonian syndrome
Pahtogenesis of JE (5 steps)
- Mosquito bites
- Multiplication in RE system
- Viremia
- Transport to Brain
- Proliferation and damage
JE hosts/vectors
Animals can act as hosts/intermediates
Humans are DEAD-END hosts
JE Treatment
None
JE vaccine
Who is it recommended for?
Purified formalin-inactivated vaccine (3 doses)
NOT RECOMMENDED FOR TRAVELERS