Arboviruses Flashcards
Arboviruses are ________-borne viruses: vectors are usually ______ and _____.
All contain RNA/DNA? and All are enveloped/ unenveloped?.
T or F humans are not dead end hosts?
Arthropod; Mosquitoes and ticks.
RNA; Enveloped
False; humans Are dead end hosts.
Outcome of arbovirus depends of 3 things
1) specific viral agent
2) age of patient
3) Extent to which encephalitis develops.
Diagnosis of Arbovirus:
____ antibody capture ELISA.
_____ sample is the easiest.
IgM antibody.
can also add virus-specific monoclonal antibodies to increase specificity.
CSF.
Culture of arbovirus is NOT/ VERY typical?
Not
How come NAT testing of Reverse transcriptase-based PCR of RNA genome of Arbovirus not reliable in acute phase?
Viremia is ofter weak and transient.
To ensure further viral transmission of arbovirus the animal must have a titer higher than______.
10^4.
1) Humans are tangetial hosts accidentally entering a natural zoonotic transmission cycle.
2) Large human population coexisting with large vector population such as mosquitoes?
Which one is Sylvatic cycle and which is Urban Cycle?
1) Sylvatic
2) Urban
Encephalitis definition
S/S’s indicating involvement of brain parenchyma
Seizures, alteration of consciousness, visual disturbances, paralysis of extremities.
What are the long term deficits in children after ARbovirus?
Deafness
Psychomotor difficulties
Learning disabilites
WEE vector is most active where and when?
Rural areas and at sunset
EEE and VEE vectors are active when?
Daytime
The Togaviridae is ___veloped; ss (__)RNA.
Where does replication take place?
enveloped; +
Cytoplasmic replication.
What are the 3 encephalitis’s and 1 fever under The Flaviviridae?
3) St. Louis/ West Nile/ Japanese
1) Yellow Fever.
What is the genome of the Bunyaviridae?
What are the two physical features of the Bunyaviridae?
3 circular segments of ss(-) RNA
It is enveloped and Spherical.
What is the Encephalitis associated with the Bunyaviridae?
California Encephalitis.
What are the 2 reservoirs and 1 vector of EEE?
Resevoir: Bird and Horse
Vector: Mosquito
True or False:
EEE has the lowest fatality rate.
False; up to 70% of cases are fatal.
Mose WEE cases are in what age group?
Infants and children under 10 years of age.
Are Sequelae common in children or adults?
What are some examples?
Children
Convulsions; motor/behavioral changes in over 50% of children infected in first month of life.
What is the reservoir and vector of St. Louis encephalitis?
What is the amplifying host?
Bird reservoir with Mosquito vector.
Sparrows
What is the most serious manifestation of WNV?
Fatal encephalitis in humans as well as horses and birds.
What is the most important predictive factors for the severe disease in WNV?
Advanced age >50
What are the 2 reservoirs and 1 vector of Japanese Encephalitis?
2) Pig and Water Bird
1) Mosquito
Japanese Encephalitis is Vaccine preventable true or false?
True
What is the most common Serogroup of the California encephalitis?
LaCrosse
What is the age group of the bunyaviruses?
School aged children.
6months-16 years, boys.
What kind of virus is colorado tick fever?
Describe its genome.
Reovirus.
DS RNA genome of 12 segments.
What is the vector of CTF?
What are the 2 reservoirs of CTF?
Tick
Squirrels and Chipmunks.
What do most individuals have a history of with CTF?
History of tick exposure.
What is the common presentation of CTF?
And why shouldnt CTF patients donate blood for at least 6 months.
Saddle backed fever pattern.
virus can persist for months in erythrocytes.
