Pelzer Flashcards
What is the most common arboviral disease in the US?
West Nile Virus
What type of virus is WNV?
Flavivirus
How is WNV transmitted?
mosquitos, blood transfusions, organ donations; what sucks is that blood is screened, but organs are not
What animal is the reservoir for WNV?
Passerine birds aka perching birds
What 3 species are primarily effected by WNV?
humans, horses, crows and jays
When do we see most cases of WNV (traditionally)?
late summer, early fall; but climate change…
Are humans typically asymptomatic or symptomatic with WNV?
Asymptomatic- 80%
If humans present symptomatically with WNV, what is the typical presentation?
flu like symptoms: sore throat, muscle aches, headaches, lymphadenopathy
What is the percentage of humans infected w/ WNV that are symptomatic? If they are symptomatic, what is the chance of getting the neuroinvasive form?
20%; 1:150
What population (humans) is more at risk for WNV?
> 50 yrs
How do horses present when infected w/ WNV?
fever, encephalomyelitis, muscle twitching, ataxia
How is St. Louis Encephalitis transmitted?
the damn mosquitos again
What is the reservoir for St. Louis Encephalitis?
birds
Why do we see a cluster of infections (in humans) of St Louis Encephalitis in low socioeconomic and older neighborhoods?
decreased trash collection, decreased in maintenance/ repair –> increase in breeding grounds for the mosquitos; less access to adequate medical care
Where do the annual cases of EEE occur in VA?
Tidewater area
Why does the Tidewater area see cases of EEE in VA?
fresh water swamps are breeding ground for mosquitos
Can humans get EEE?
Yes, but they are accidental hosts.
What are the clinical signs assc w/ EEE in a human?
fever, headache, vx, lethargy, aseptic meningitis, or encephalitis delirium, and coma
What population is at risk for severe disease assc w/ EEE?
Children under 15yrs and adults 50yrs>
What is the case fatality rate of those infected w/ EEE?
30%
What is the reservoir for EEE?
passerine birds AND water fowl
What population is at risk for clinical signs (in humans) in regards to WEE?
young adults and <1 yr
In what infection will a child transition from fever, headache, stiff neck, spastic paralysis, and mental confusion -> personality changes, mental retardation, and continued spastic paralysis?
WEE
What is the equine encephalitis that does not have birds as its reservoir?
VEE