Survey of medical virology (-) strand RNA viruses Flashcards
(141 cards)
1
Q
What is the pro name for rabies virus?
A
rhabdoviridae
2
Q
With negative sense RNA viruses, what must be included in the virion?
A
RNA-dependent RNA polymerase
3
Q
What is essential for the replication of RNA viruses in cytoplasma?
A
Viral encoded RNA-dependent RNA polymerase
4
Q
What kind of virus is the rabies virus?
A
rhabdoviridae- lyssavirus- rabies virus
5
Q
What is the ONLY medically important rhabdovirus?
A
rabies
6
Q
What kind of range does rabies have?
A
broad host range, infects all mammals
7
Q
How is rabies transmitted?
A
by the bite of a rabid animal (bats, raccoons, skunks)
8
Q
How many cases of rabies are in the US?
worldwide?
A
less than 10 cases/yr
50,000 worldwide
9
Q
What is the incubation period of rabies?
A
2 weeks to year
10
Q
What are the 2 phases of rabies infection?
A
prodrome phase
neurological phase
11
Q
What are the symptoms of the prodrome phase of rabies?
A
fever, nausea, headache, spread to CNS from muscle
12
Q
What are the symptoms of the neurologica phase?
A
hydrophobia, anxiety, paralysis, coma, death (~100%)
13
Q
If you have been bitten by a rabid animal what shoud you do?
A
get vaccine and human rabies IgG
14
Q
How do you diagnose rabies?
A
cytologic detection of inclusion bodies (Negri bodies) or immunochemical detection of viral antigen in brain tissue
15
Q
a 20-year-old man is brought to the emergency department by his roommate because of numbness in his hand and arm, irritability, combativeness, and episodes of hyperactivity during the past week. He refuses to drink any liquids. He was bitten on the hand by a bat while trying to chase it out of his apartment about a month ago but didn’t seek medical attention. What is this?
A
Rhabdoviridae-lyssavirus-rabies virus
16
Q
What kind of virus is Ebola and Marburg virus?
A
Filovirus
17
Q
What does eboa and marburg virus cause and what is the mortality rate?
A
hemorrhagic fever
greater than 90% mortality
18
Q
What is the likely reservoir for Ebola and Marburg virus?
A
bats
19
Q
How is ebola and marburg virus transmitted?
A
by direct contact with contaminated body fluids
20
Q
What does ebola and marburg virus infect?
A
infects macrophages and spreads via blood
21
Q
Ebola and Marburg cause tissue destruction due to release of (blank) causing what?
A
cytokines
vascular permeability, hemorrhage and shock
22
Q
What are the clinical symptoms of Eboa and Marburg virus?
A
severe hemorrhagic fever
eventual bleeding into skin, mucous membranes, and visceral organs
Death by multiorgan failure and shock
23
Q
Is there a specific treatment or vaccine against ebola and marburg virus?
A
NO :(
24
Q
How do you diagnose ebola and marburg virus?
A
immunoassay, PCR, serology
25
What are the symptoms of severe hemorrhagic fever?
sudden fever
headache
joint and muscle pain
vomiting diarrhea
26
A 55-year-old male native of Sudan is brought to Yambio Hospital with sudden onset of fever, muscle pain, and headache followed by intense weakness, vomiting and diarrhea. The patient was admitted to an isolation ward where his condition deteriorated with hemorrhage into the skin, mucous membranes, and internal organs. He died 12 hours later.
What is this?
Filovirus- Ebola and Marburg virus
27
What kind of virus is the influenza virus?
orthomyxovirus
28
How does the influenza virus replicate?
1 receptor mediated endocytosis
2. segmented ribonucleoproteins released into the cytoplasm
3. genoma transported to the nucleus
4. replication and transcription
5. viral mRNAs transported to the cytoplasm for translation
6. early viral replication proteins transported back to the nucleus
7. assembly and budding occurs at the PM
29
(blank) sickens and kills thousands/year; may cause pandemics
influenza
30
app. (blank) people die of influenze each year in the US
36,000
31
How is the influenza virus transmitted?
by respiratory droplets
32
Pandemics are caused by what strain of influenza?
A and B
| C is milder infection
33
Which influenze virus is this:
| 16 antigenic types of HA and 9 types of (NA).
influenza A virus
34
What creatures can influenza A infect?
birds, chickens, pigs
35
what is an antigenic shift?
reassortment of segments of the genome RNA
36
What is antigenic drift?
small mutations in the genome RNA
37
Antigenic changes to (blank) and (blank) causes epidemics and pandemics
HA and NA
38
Two surface glycoproteins of influenza virus are (blank and blank)
haemagglutinin (HA) and neuraminidase (NA),
39
After incubation period of 24-48 hours what will influenza virus make happen to you poor body?
fever, myalgia, headache, sore throat, and cough will develop suddenly
40
Who are at risk of dying via influenza virus?
elderly and those with cardiac or pulmonary disease at high risk
41
When will symptoms of influenza resolve? What might complicate this course?
4 to 7 days
| pneumonia
42
Immunity against influenza virus depends on (blank).
secretory IgA targeting HA in the respiratory tract
43
How do you diagnose the flu?
on clinical grounds but lab tests are available
44
What are used for both the treatment and prevention of influenza?
Oseltamivir (Tamiflu) and zanamivir (Relenza)
45
how do you prevent Influenza virus?
VACCINE! (which is reformulated every ) which consists of influenza A and influenza B
46
A 70-year-old women with a history of congestive heart failure is seen in January by her primary care physician with an abrupt onset of fever, cough, and myalgia that requires hospitalization. Two days later, she experiences increasing cough and shortness of breath. Chest X-ray reveals lung infiltrates.
What is this?
Influenza virus
47
What kind of virus is measles virus?
parmyxovirus -morbillivirus- measles virus
48
Measles is a disease characterized by a (blan)
maculopapular rash
49
How is the measles virus transmitted?
respiratory droplets
50
Who estimates (blank) cases of measles each year worldwide
30 million
51
HOw does the measles virus work?
infects respiratory tract then spreads in blood via phagocytic cells
52
How long is the incubation period of measles and what happens after this is over?
10-14 days
| fever, conjuctivitis, runny nose and cough followed by rash that spreads from face to extremities
53
Whats a symptom that is seen on the buccal mucosa and is associated with measles virus?
Koplick spots
54
How often do you get encephalitis from measles?
1 per 1000 cases of measles
55
How can you prevent meases?
vaccination with live attenuate virus
56
A 20-year-old college student is seen in the student health clinic with complaints of high fever, cough, and conjunctivitis. Physical examination reveals small vesicular lesions on an inflamed buccal mucosa and a rash on her face that is spreading to her trunk. She retuned from India 2 weeks earlier. She is unvaccinated because of a personal believe exception.
paramyxovirus-morbillivirius-measles virus
57
What type of virus is parainfluenza virus?
paramyxovirus
58
What does PIV cause?
croup, laryngitis, bronchiolitis, and pneumonia in children
| looks like common cold in adults
59
How are PIVs transmitted?
via respiratory droplets
60
(blank) is main cause of croup in children younger than 5 years old
PIV 1 and PIV 2
61
Croups is characterized by what?
barking cough and hoarsness
62
PIV can cause a variety of respiratory diseases such as....?
cold, pharyngitis, laryngitis, otitis media, bronchitis, pneumonia
63
Where do you see PIV 3?
lower respiratory infections in children
64
How do you diagnose PIV 3?
clinically
65
A 2-year-old child is brought to the emergency department by worried parents because of a barking cough and inspiratory stridor that got worse at night. The present illness began 2 days earlier with a fever, sore throat, rhinorrhea, and mild cough. Finding on examination include a temperature of 102oF, tachypnea, wheezing, and respiratory distress
paramyxovirus-parainfluenza virus
66
What kind of virus is the mumps?
paramyxovirus
67
What do the mumps cause?
painful swelling of the parotid gland
68
Mumps occurs primarily in (blank) and is transmitted via (blank)
childhood
| respiratory droplets
69
How many serotypes of mumps is there?
1
70
Where does mumps infect primarily and where does it spread to?
upper respiratory tract, spread via blood to parotid glands, testes, ovaries, pancreas, and, in some cases, meninges
71
How do you diagnose the mumps?
clinically
72
Is there a high incidence of the mumps in the US?
no, it is low risk
73
how do you prevent the mumps?
live attenuated virus
74
A 7-year-old male is seen in the state health department clinic with fever, malaise, difficulty chewing and speaking, and salivary gland swelling and pain. His parents are migrant farm workers. There is no vaccination record. Physical examination is significant for a temperature of 102oF and unilateral parotitis.
Paramyxovirus-mumps
75
What kind of virus is respiratory syncytial virus?
paramyxovirus
76
RSV is the most common cause of what 2 things in infants?
pneumonia and bronchiolitis
77
Who are susceptible to RSV?
Neonates, premature infacnts, and infants with cardiopulmonary diease are susceptible
78
How is respiratory syncytial viruses transmitted?
via respiratory droplets
79
How does RSV present in adults?
as common cold and bronchitis
80
How does RSV present in elderly?
as pneumonia
81
How does RSV present in infants?
pronounced cough and expiratory wheezing
82
How can you check for RSV?
rapid antigen test in respiratory secretions
83
How do you treat RSV?
with ribavirin for severly ill hospitalized infants
OR
with passive immunization
84
A 6-week-old infant is brought to the pediatric clinic in respiratory distress. Physical examination is significant for diffuse expiratory wheezing and mild cyanosis. The chest X-ray is suggestive of bilateral pneumonia. The infant is admitted to the intensive care unit. Nasopharyngeal swab and nasopharyngeal washing are sent for culture and direct examination.
paramyxovirus-RSV
85
What kind of virus is metapneumovirus?
paramyxovirus
86
What is metapneumovirus a signif cause of?
acute respiratory diease in infants and children
87
Metapneumovirus is second to RSV in causing (Blank) during winter months
bronchiolitis
88
How does metapneumovirus spread?
respiratory droplets
89
How does metapneumovirus clinically present?
causes mild respiratory infection in general community
90
How do you detect metapneumoirus?
genome detection by PCR assay of respiratory secretions
91
Is there a known treatment for metapneumovirus?
no known treatment
92
An 11-month old male is seen in a pediatric practice in February with symptoms of a nonproductive cough, nasal congestion, rhinorrhea, fever, and irritability. Physical examination was significant of a temperature of 101.5oF, rhinitis, and wheezing. A chest X-ray revealed pulmonary infiltrates. The child was admitted to the intensive care unit. Nasopharyngeal washings were negative for RSV.
What is this?
metapneumovirus
| remember that RSV present very similiarly to metapneumovirus
93
What kind of virus is the Hantavirus?
it is a bunyaviridae virus
94
How do you get the hantavirus?
inhaled rodent feces and urine
95
Where do you get hantavirus replication?
pulmonary capillary endothelial cells
96
What can the hantavirus infect?
renal resulting in hantavirus fever with renal syndrome (HFRS) which is prevalent in Europe, Asia, Africa
Pulmonary resulting in hantavirus pulmonary syndrome (HPS) found in US
97
(blank) is endemic in deer mice in western US (new mexico, arizona)
HPS
98
How does HPS present itself?
influenze like symptoms followed by respiratory failure
99
HPS mortality rate is very high (35%) T or F?
T
100
How do you detect HPS?
detect viral RNA in lung tissue, PCR, immunohistochemistry, IgM
101
Is there a vaccine or effective drug against HPS?
nO
102
An otherwise healthy 28-year-old male biology graduate student presented to the emergency department with sudden onset of high-grade fever, myalgia, cough, and dyspnea. His condition deteriorated rapidly, with the patient becoming hypoxic and requiring mechanical ventilation. Chest X-ray showed evidence of bilateral infiltrates. Patient history was significant for doing recent small mammal (including mice) field research in a Colorado research forest.
Bunyaviridae-Hantavirus
103
What kind of virus is california encephalitis virus?
bunyviridae virus AND it is an arbovirus (mosquito)
104
CE subtype that causes encephalitis is most often (blank)
La Crosse Viruse (LACV)
105
What is the most common arboviral disease in US?
LACV-mediated encephalitis
106
HOw prevelant is CEV?
about 70 cases a year and most cases in summer with kids under age of 16
107
How does CEV present?
severe headache, fever, possibly vomiting and convulsions. Half the patients develop seizures
108
What is the mortality rate of CEV and how do you diagnose it?
1% (aseptic meningitis)
| serologically for IgM or IgG
109
Is there a vaccine or effective drug against CEV?
no but if you are seropositive you are protected against reinfection
110
What kind of virus is Crimean congo hemorrhagic fever?
Bunyaviridae
111
Where is tickborne viral diseases common?
Africa, eastern Europe, Asia
112
What is the mortality rate of Crimean congo hemorrhagic fever?
3-30%
113
How do you get Crimean congo hemorrhagic fever?
handing infected mammals or humans
114
What does Crimean congo hemorrhagic fever cause?
extensive liver damage (hepatomegaly)
115
How does Crimean congo hemorrhagic fever present?
Initially: fever, headache, myalgia, dizziness, and mental confusion
Hemorrhagic Phase: bleeding from nose, GI, uterus, respiratory
116
How do you diagnose Crimean congo hemorrhagic fever? How can you treat this?
serology
| ribavirin may be helpful
117
What kind of virus is Rift Valley Fever virus?
Bunyaviridae
118
How is Rift Valley fever virus created?
it is mosquito-borne virus pathogenic primarily for domestic livestock
119
Most human cases of Rift Valley Fever Virus are caused how?
zoonotic via infected livestock tissue
120
Most causes of Rift Valley Fever Virus are found where?
sub-Saharan Africa and Egypt; many outbreaks
121
What is the presentation of Rift Valley Fever Virus?
causes mild febrile illness
| recovery is almost always complete
122
What are some complications associated with Rift Valley Fever Virus?
- retinitis, encephalitis, and hemorrhagic fever
| - Permanent loss of vision (1-10% of retinitis cases) 1% of patients die.
123
How do you diagnose Rift Valley Fever Virus?
viral isolation from tissues, or serological via ELISA
124
What kind of virus is lymphocytic choriomeningitis (LCM)?
Arenaviridae virus
125
How is LCM transmitted?
via aerosol inhalation, ingestion of contaminated food
126
What are common resevoirs form LCM?
house mouse or hamsters
127
T or F
| LCM has a worldwide distribution with a low case fatality rate (<1%).
T
128
T or F
| Most LCM infections are asymptomatic
T
129
What does LCM present like?
influenza like symptoms, fever, headache, stiff neck in minority of patients
130
Is there a treatment or vaccine for LCM?
no treatment or vaccine
131
How do you test for LCM?
serological testing for IgM or IgG is routine
132
What kind of virus is Lassa Fever virus?
Arenaviridae virus
133
How do you get Lassa Fever virus transmission?
Aerosol transmission or contract with rodent excretions OR person to person spread by contact with blood, secretions, excretions
134
What is Lassa fever endemic to?
west africa (field rate is the reservoir (Lassa, Nigeria)
135
How prevalent is Lassa Fever?
300,000 and 500,000 cases, resulting in 5,000 deaths per year
136
What does Lassa Fever virus cause?
severe hemorhagic fever, myalgia, and severe prostration.
137
Where does Lassa Fever virus enter the body?
| Where does it spread to and how?
via skin abrasion or inhalation and replicates in lymph node. Viremia develops and spreads systemically via macrophages
138
Is there a vaccine and how do you treat Lassa Fever virus?
no vaccine, ribavirin is useful treatment
139
How do you test for Lassa Fever virus?
serologic testing for IgM or IgG
140
What is prostration?
extreme exhaustion or lack of energy or power
141
A 35-year-old female became ill with fever and flu-like symptoms after spending 4 months traveling on a medical mission to Nigeria. Her symptoms worsened upon returning to her home in New Jersey, where she sought treatment and was hospitalized for fever (103.6oF), headache, vomiting, and diarrhea leading to severe prostration. Her condition deteriorated and she was intubated and mechanically ventilated.
What is this?
Arenaviridae- Lassa Fever Virus
