Bunya, Arena, Filo virus Flashcards
1
Q
Th e arboviruses are transmitted by bloodsucking
arthropods from one vertebrate host to another. Th e viruses multiply in the tissues
of the arthropod without evidence of disease or damage. True or False?
A
True
2
Q
Viral
infection is usually persistent in rodent-borne viral diseases True or False?
A
True
3
Q
ID genus: Guanarito Junin Machupo Sabia Whitewater Arroyo
A
Genus Arenavirus - New World
4
Q
ID genus:
Lassa
lymphocytic choriomeningitis viruses
A
Genus Arenavirus - Old World
5
Q
ID genus: Anopheles A and Bunyamwera California encephalitis Guama La Crosse Oropouche Turlock viruses
A
Genus Orthobunyavirus, family Bunyaviridae
6
Q
ID genus: Hantaan virus (Korean hemorrhagic fever) Seoul virus (hemorrhagic fever with renal syndrome) Sin Nombre virus (hantavirus pulmonary syndrome)
A
Genus Hantavirus, family Bunyaviridae
7
Q
ID genus:
Arthropod borne (ticks)
Crimean-Congo hemorrhagic fever Nairobi sheep disease
Sakhalin viruses.
A
Genus Nairovirus, family Bunyaviridae
8
Q
ID genus: Arthropod borne (mosquitoes, sandflies, ticks) Rift Valley fever sandfly (Phlebotomus) fever Uukuniemi viruses
A
Genus Phlebovirus, family Bunyaviridae
9
Q
FILL IN THE PROPERTIES - ARENAVIRIDAE Virion shape: Virion content: Genome segment: Genome sense: Genome: Proteins: Envelope: Replication: Assembly:
A
ARENAVIRIDAE Virion shape: spherical Virion content: transcriptase Genome segment: double-segmented Genome sense: negative-sense AND ambisense Genome: ssRNA Proteins: 4 major polypeptides Envelope: Yes Replication: Cytoplasm Assembly: Incorporate ribosomes and bud from PM
10
Q
FILL IN THE PROPERTIES - BUNYAVIRIDAE Virion shape: Virion content: Genome segment: Genome sense: Genome: Proteins: Envelope: Replication: Assembly:
A
BUNYAVIRIDAE Virion shape: spherical Virion content: transcriptase Genome segment: triple-segmented Genome sense: negative-sense OR ambisense Genome: ssRNA Proteins: 4 major polypeptides Envelope: Yes Replication: Cytoplasm Assembly:budding into the Golgi
11
Q
FILL IN THE PROPERTIES - FILOVIRIDAE Virion shape: Virion content: Genome segment: Genome sense: Genome: Proteins: Envelope: Replication: Assembly:
A
FILOVIRIDAE Virion shape: long filaments Virion content: transcriptase Genome segment: NON-segmented Genome sense: negative-sense Genome: ssRNA Proteins: 7 polypeptides Envelope: Yes Replication: Cytoplasm Assembly: budding from PM
12
Q
Bunyaviruses are sensitive
to inactivation by (4)?
A
heat, detergents, formaldehyde, and low
pH
13
Q
Which family has hemagglutinating properties?
A
Bunyaviridae
14
Q
The _______ comprises 14
antigenically related viruses in the Orthobunyavirus genus of
the family.
A
California encephalitis virus complex
15
Q
A major cause of encephalitis and aseptic meningitis
in children, particularly in the upper Midwest.
Most cases
occur between July and September in children younger than
the age of 16 years
A
La Crosse virus
Genus Orthobunyavirus, family Bunyaviridae
16
Q
The viruses under California encephalitis virus complex are transmitted by?
A
woodland mosquitoes,
primarily Aedes triseriatus
17
Q
Principal vertebrate
hosts of California encephalitis virus complex are?
A
small mammals: squirrels, chipmunks, rabbits
18
Q
Human infection of California encephalitis virus complex is?
A
tangential
19
Q
Overwintering can occur in eggs of the mosquito vector in which viruses?
A
California encephalitis virus complex
20
Q
How is the California encephalitis virus complex transmitted?
A
Transovarially
21
Q
Describe the onset of California encephalitis virus
A
The onset of California encephalitis viral infection is abrupt, typically with severe headache, fever, and in some cases vomiting and convulsions.
22
Q
California encephalitis virus lasts from ___ days, although convalescence may be prolonged.
A
10 to 14
23
Q
Neurologic sequelae are rare in California encephalitis virus. True or False?
A
True
24
Q
Serologic confirmation by _______ is done on acute and convalescent
specimens of California encephalitis virus.
A
HI, ELISA, or neutralization tests
25
A mild, insect-borne disease that occurs commonly
| in countries bordering the Mediterranean Sea and in Russia, Iran, Pakistan, India, Panama, Brazil, and Trinidad.
Sandfly fever (also called Phlebotomus fever)
26
Sandfly fever (also called Phlebotomus fever) is transmitted by the female sandfly _____
Phlebotomus papatasii
27
In the tropics, the sandfly is prevalent all year; in cooler climates, only during the warm seasons. How is sandfly virus transmitted?
Transovarially
28
In endemic areas, infection is common in childhood.
When nonimmune adults (eg, troops) arrive, large outbreaks can occur among the new arrivals and are occasionally mistaken for malaria. Which virus is this?
Sandfly virus
29
In humans, the bite of the sandfly results in?
In humans, the bite of the sandfly results in small itching papules on the skin that persist for up to 5 days.
30
The disease
begins abruptly after an incubation period of ___ days.
The virus is found in the blood briefly near the time of onset of symptoms.
3–6
31
Clinical features consist of headache, malaise,
| nausea, fever, _____ (4)
photophobia, stiffness of the neck and back,
| abdominal pain, and leukopenia
32
Sandflies are most common just above the ground.
Because of their small size, they can pass through ordinary screens and mosquito nets.
The insects feed primarily at what time?
At night
33
The agent of Rift Valley Fever, a bunyavirus of the Phlebovirus
genus, is a mosquito-borne zoonotic virus pathogenic primarily
for?
domestic livestock
34
Infection of Rift Valley Fever is common among?
Among laboratory workers
35
Epizootics of Rift Valley Fever occur periodically after heavy rains that allow hatches of the primary vector and reservoir _____
Aedes species mosquitoes
36
Transmission
| to humans of Rift Valley Fever is primarily by?
contact with infected animal blood and body fluids and mosquito bites
37
Recovery almost always is complete in Rift Valley Fever. Complications include ____ (3). ______ may occur (1–10% of
cases with retinitis).
retinitis, encephalitis, and hemorrhagic fever
Permanent loss of vision may occur (1–10% of
cases with retinitis).
38
This virus spread in 1977 to Egypt, where it caused enormous losses of sheep and cattle and thousands of human cases, with 600 deaths.
Rift Valley Fever virus
39
RODENT-BORNE ASIAN HEMORRHAGIC FEVERS
Hantaan and Seoul viruses
40
RODENT-BORNE SOUTH AMERICAN HEMORRHAGIC
| FEVERS
Junin and Machupo viruses
41
RODENT-BORNE SOUTH AFRICAN HEMORRHAGIC
| FEVERS
Sin Nombre virus
42
The Hantavirus infections in rodents are lifelong and without
deleterious effects. True or False?
True
43
How is the presence of hantavirus-associated disease determined?
The presence of hantavirus-associated diseases is determined by the geographic distribution of the rodent reservoirs.
44
An acute viral infection that causes an interstitial nephritis that can
lead to acute renal insufficiency and renal failure in severe
forms of the disease.
Hemorrhagic fever with renal syndrome (HFRS)
45
Identify the hantaviruses that cause hemorrhagic fever with renal syndrome (HFRS) according to severity, with the most severe last.
1. PUMULA VIRUS: causes nephropathia epidemica, prevalent in Scandinavia
2. Seoul virus in Eurasia
3. Hantaan and Dobrava viruses in China, Russia, Korea, the Balkans
46
More than 2000 cases of HFRS occurred among United Nations troops during the Korean War, but Hantaan virus was not isolated until 1976 in Korea from a rodent, _____.
Apodemus agrarius (urban rats)
47
What could have dispersed hantaviruses worldwide?
Trading ships, among longshoremen
48
HFRS is treated using?
Supportive therapy
49
In 1993, an outbreak of severe respiratory illness occurred in the United States, now designated the hantavirus pulmonary
syndrome (HPS). It was found to be caused by a novel hantavirus, ______
Sin Nombre virus
50
Primary disease caused by Sin Nombre virus.
Adult RDS
51
Vector of Sin Nombre virus
deer mouse (Peromyscus maniculatus)
52
Other hantaviruses known to cause HPS in the United States include New York virus, Black
Creek Canal virus, and Bayou virus, each having a different rodent host. Identify the rodent hosts
New York virus: Peromyscus leucopus
Black Creek Canal virus:
Sigmodon hispidus
Bayou virus: Oryzomys palustris
53
Virus transmitted by Oligoryzomys longicaudatus
Andes virus, Argentina and Chile
54
Virus transmitted by Oligoryzomys costaricensis
Choclo virus, Panama
55
HPS is generally severe, with reported mortality rates of 30% or greater. This case-fatality rate is substantially higher than that of other hantavirus
infections. The disease begins with ____, _____ and _____ followed by _______.
The disease begins with fever, headache, and
| myalgia followed by rapidly progressive pulmonary edema, often leading to severe respiratory compromise.
56
Hantaviral antigens are detected in endothelial cells and macrophages in (4)?
lung, heart, spleen, and lymph nodes
57
Pathogenesis of HPS involves the _______?
functional
| impairment of vascular endothelium
58
Person-to-person transmission of hantaviruses seldom occurs, although it has been observed during outbreaks of HPS
caused by _____.
Andes virus
59
Laboratory diagnosis depends on detection of viral nucleic acid by ______ , detection of viral antigens in fixed
tissues by ____, or detection of specific
antibodies using recombinant proteins.
RT-PCR
| immunohistochemistry
60
An _____ to
| detect IgM antibodies may be used to diagnose acute infections of HPS.
ELISA test
61
A fourfold rise in ______ between acute and
| convalescent sera is diagnostic of HPS.
IgG antibody titer
62
The antiviral drug _____ is of some benefit as therapy
| in HPS.
ribavirin
63
In HPS, care must be taken to avoid inhaling _____ when cleaning rodent-infested structures.
aerosolized dried
| excreta
64
Based on sequence data, arenaviruses are divided into Old World viruses (eg, Lassa virus) and New World viruses.
The latter division is divided into three groups, with group A
including _____ and group B containing the human
pathogenic viruses, such as _____.
Pichinde virus
| Machupo virus
65
An arena virus that appears to be recombinants between New World lineages A and B.
Whitewater Arroyo virus
66
Humans are infected with arenaviruses when they come in contact with ______.
rodent excreta
67
Multiple arenaviruses cause human disease; _____ conditions are required
in the laboratory.
high-level containment
68
Aside from excreta, arena viruses may be transmitted by?
milk, saliva and urine
69
Arenaviruses cytopathic
| effects when replicating in cultured cells. True or False?
False.
Arenaviruses typically do not cause cytopathic
effects when replicating in cultured cells.
70
Host ribosomes are encapsidated during the morphogenesis
| of arena virus particles. True or False?
True
71
This virus is active in all western African countries situated between Senegal and Republic of Congo.
Lassa virus
72
The incubation period for Lassa fever is 1–3 weeks from time of exposure. Onset is gradual, with _______.
fever, vomiting, and back and chest pain
73
There is skin rash in Lassa fever. True or false?
True. Skin rash with hemorrhages
74
A common complication of Lassa virus affecting about 25% of patients during recovery.
Deafness
| Hearing loss is permanent
75
During the third trimester, maternal
mortality is increased (30%), and fetal mortality is very high
(>90%) in which infection?
Lassa Fever
76
Diagnosis of Lassa virus usually involves ______ by ELISA.
detection of IgM and IgG antibodies
77
Principal rodent reservoir of Lassa virus.
house rat (Mastomys natalensis)
78
Lassa virus can be transmitted by human-to-human contact. True or false?
True
79
Drug of choice for Lassa fever and is most effective if given early in the disease process.
Ribavirin
80
No vaccine exists, although a vaccinia virus recombinant that
expresses the glycoprotein gene of Lassa virus is able to induce protective immunity both in guinea pigs and in monkeys. True or False?
True.
81
Based on both serologic and phylogenetic studies of viral RNA, the South American arenaviruses are all considered
to be members of the __________.
Tacaribe complex
82
Based on both serologic and phylogenetic studies of viral RNA, the South American arenaviruses are all considered to be members of the Tacaribe complex. Most have _____ reservoirs.
cricetid rodent
83
Bleeding is more common in Lassa fever than in Argentine (Junin) and other
South American hemorrhagic fevers. True or False?
False. Bleeding is more common in Argentine (Junin) and other
South American hemorrhagic fevers than in Lassa fever.
84
a major public health problem in certain agricultural areas of Argentina
Junin hemorrhagic fever (Argentine hemorrhagic
| fever)
85
The disease has a marked seasonal variation, and
the infection occurs almost exclusively among workers in
maize and wheat fields who are exposed to the reservoir
rodent, Calomys musculinus.
Junin hemorrhagic fever (Argentine hemorrhagic
| fever)
86
Rodent reservoir of Junin hemorrhagic fever (Argentine hemorrhagic
fever)
Calomys musculinus
87
Junin virus produces both humoral and cell-mediated
immunodepression; deaths caused by Junin hemorrhagic
fever may be related to an inability to initiate a _____.
cell-mediated
| immune response
88
Administration of _____ to patients during the first week of illness reduced the mortality rate from 15–30% to 1% in Junin hemorrhagic fever (Argentine hemorrhagic
fever)
convalescent human
| plasma
89
An effective live-attenuated vaccine is available for Junin hemorrhagic fever. True or False.
True
90
Rodent reservoir of Machupo hemorrhagic fever (Bolivian hemorrhagic fever)
Calomys callosus
91
The emergence of this virus was tied to clearance of forest land for small farm use.
Guanarito virus (the agent of Venezuelan hemorrhagic fever)
92
Isolated in 1990 from a fatal case of hemorrhagic fever in Brazil.
Sabia virus
93
induce a clinical disease resembling that of
| Argentine hemorrhagic fever
Guanarito virus and Sabia virus
94
Lymphocytic choriomeningitis (LCM) virus' natural vector
wild house mouse, Mus musculus
95
It may chronically infect mouse or hamster colonies and may infect
pet rodents.
Lymphocytic choriomeningitis (LCM) virus
96
LCM in humans is an
acute disease manifested by aseptic meningitis or a mild systemic influenza-like illness. It is rarely fatal. True or False?
True
97
In 2005, four solid-organ transplant recipients in the United States became infected from
a common organ donor. Three of the four organ recipients died 23–27 days after transplantation. Which virus caused this?.
Lymphocytic choriomeningitis (LCM) virus
98
The Lymphocytic choriomeningitis (LCM) virus has no mother-to-fetus transmission in utero. True or False.
False.
99
Infections are usually diagnosed retrospectively by serology using ELISA for IgM and IgG antibodies. Other diagnostic approaches include immunohistochemical staining of tissues for viral antigens, RT-PCR for viral nucleic acid, and viral culture using Vero cells. Which virus is this?
Lymphocytic choriomeningitis (LCM) virus
100
Experimental studies have shown that the immune response may be protective or deleterious in LCM virus infected mice. The result
depends on the?
age, immune status, and genetic background
of the mouse
the route of inoculation of the virus
