Arboviruses

Question 1

1. Define an arbovirus and name which three taxonomic families include most arboviruses.

Answer 1

bunya, flavi, toga

go between invertebrates and vertebrates
rna genome
mosquitos ticks biting flies

hosts can be a reservoir or non reservoir based on ho much of virmeia happens

humans are dead end hosts

Question 2

2. Name the major human disease outcomes associated with arboviral infection and describe how arboviral diseases are diagnosed.

Answer 2

dead end
west nile
eastern equine encephalitis
japanese encephalitis 
la crosse

not dead end
zika
dengue
yellow fever
alpha

common outcomes:
most asymptomatic
2nd most febrile illness
neuolgic disease
arthritis
hemmorhagic fever

Question 3

3. Describe the transmission cycle of arboviruses, including: vectors, reservoir hosts, incidental hosts, and dead-end hosts; factors that determine reservoir hosts and vectors; whether humans can function as reservoir hosts for arboviruses; and reasons why other blood-borne viruses, like HIV, HBV, and HCV, are not arboviruses.

Answer 3

mosquitos- has to replicate and get into saliva–> 8-12 days

Question 4

Dengue (4 serotype)

Answer 4

commonly asymptomatic

1. dengue fever
   - HA muscle joint rash
2. dengue hemmorhagic fever/dengue shock fever
   - thrombocytopenia, capillary leakage, dmagae to liver, fluid extravasation–> shock

Question 5

how is Dngue maintained

Answer 5

human mosquito human transmission cycle

Question 6

whats risk factor for development of the worse dengue virus infection

Answer 6

a second infection by a different serotype

-antibody dependent enhancement of disease severity

Question 7

Chikungunya vrius

Answer 7

re-emergence of mosquito transmitted alpha virus
chronic musculoskeletal disease

acute- fever, pain in joints
post acute- persistent

Question 8

Zika virus

Answer 8

flavivirus
asymptomatic, or low level

microcephaly of baby

Question 9

west nile

Answer 9

arbo virus
febrile, weak, GI issues, neck stiffness
altered mental status
enzootic cycle with birds and mosquitos

neuro invasive diasease occurs in elderly
non mosquito spread through blood transfusion
-check with rt-pcr