Emerging Viruses I and II Flashcards
1
Q
Hantavirus
- mortality rate
- family
- Virus name
- Disease
- Reservoir
- Distribution
A
- high, 50-67%
- Bunyavrirdae
- Sin Nombre
- Pulmonary syndrome- pneumonia
- deer mice
- N. America
2
Q
Hantavirus
- genome
- what is seen on X-ray?
- Transmission
- Treatment
- Detection
A
- negative strand, segmented RNA
- diffuse infiltrate
- inhalation of virus particles present in mouse feces and urine; NOT human-human
- aggressive respiratory support
- specific IgM in pt serum
3
Q
Arboviruses
- Which viruses are transmitted by mosquitoes or ticks?
- Which viruses are transmitted by animals or animal bites?
A
- Togaviridae, Flaviviridae, Bunyaviridae, Reoviridae
2. Arenaviridae, Rhabdoviridae, Filoviridae
4
Q
4 Major Cycles by which arboviruses are transmitted
A
- insect, bird, insect –> man (dead end host) or horse (dead end host)
- Insect, monkey, insect, man, insect, man (urban cycle)
- inset, goat, insect, goat, man (via goat milk); man is dead end host
- insect, bird, insect, rodent, man (dead end host); also shows transovarial transmission in mosquitos
5
Q
Arbovirus induce 3 infections
A
- Encephalitis (fever, headache, stiff neck, altered consciousness)
- Rash-fever (fevers, headaches, myalgias, arthralgias, malaise; resolve w/o sequelae
- Hemorrhagic fevers (undifferentiated/rash fever + profuse bleeding into the skin and GI tract secondary to DIC, hypotension, shock, and leukopenia
6
Q
Arbovirus Pathogenesis
A
- Infects vascular endothelium
- virus also infects macrophages in liver in spleen
- virus can infect liver and brain –> serious disease
7
Q
Detection of Arbovirus infection
- How hard is it?
- Why?
- What methods can you do?
A
- very difficult
- don’t grow well in cell culture
- specific diagnosis by RT-PCR or by serology (high IgM or increasing IgG)
8
Q
Eastern Equine
- Geographical Distrubtion
- Age Group Affected
- Mortality
- Sequelae
- Symptoms
A
- East, Gulf Coast, South
- Children
- 50-75
- 80% of survivors- neuro symptoms
- headache, altered consciousness, seizures (fulminant)
9
Q
St Louis
- Geographical Distrubtion
- Age Group Affected
- Mortality
- Sequelae
- Symptoms
A
- Cental, West, South
- Adults > 50 y/o
- 2-20
- 20% of survivors
- headache, nausea, vomiting, disorientation, stupor, irritability
10
Q
LaCrosse
- Geographical Distrubtion
- Age Group Affected
- Mortality
- Sequelae
- Symptoms
A
- Central, East
- Children
- <1
- Low
- seizures, paralysis, focal weakness
11
Q
Yellow Fever Virus
- Family virus
- genome; envelope?
- vector
- reservoir
- transmission cycle
A
- Flaviviridae
- ssRNA, envelope
- mosquitoes
- monkeys in jungle, humans for urban cycle
- jungle cycle
12
Q
Yellow Fever
- Geographic Distribution
- Therapy
- Vaccine
A
- Endemic in equitorial areas (south america/Africa)
- no antiviral therapy
- Live-attenuated vaccine is effective; travelers should be vaccinated
13
Q
Dengue Virus
- family
- genome; envelope?
- vector
- reservoir
- cycle
- serotypes?
A
- Flaviviridae
- ssRNA, envelope
- mosquitoes
- monkey
- jungle cycle
- several, infection with one serotype seems to predispose individuals to more severe disease
14
Q
Dengue Fever
- Geographic areas
- What causes the severe infection in secondary disease?
- Disease (2)
A
- central/south americas; subsaharan africa, india and south pacific; now seen in US
- immunoresponse causes increased capillary leakage leading to more vascular permeability
- “breakbone fever”: headache, fever, pains in joints, muscles, eyeballs, maculopapular eruptions persisting 3-4 days
- Dengue hemorrhagic fever- severe hemorrhage or shock; most frequently seen in children
15
Q
Dengue Fever
- Lab Diagnosis
- Vaccine
A
1, depends on day of illness, viremia or NS1 (early); IgM or IgG later (secondary infection or late primary infection)
2. development of live-attenuated, tetravalent vaccine is ongoing