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Flashcards in Test 2 Deck (193):
1

What are the three upper respiratory viruses?

adenovirs, coronavirus (SARS), Rhinovirus

2

What anatomical features are included in the upper respiratory?

nasal cavity
throat
nostril
mouth
voice box (larynx)

3

Where was the adenovirus first isolated?

in human adenoids

4

What percentage of viral respiratory infections do adenoviruses cause

5-10%

5

What is the size in diameter of adenoviruses

80-100nm

6

The adenovirus is classified as what size in easy terms

medium

7

What is the shape of the adenovirus

icosohedral

8

How many protein subunits is the capsid of the adenovirus made up of

252 capsomeres

9

How many sides are to the adenovirus capsid

20

10

The 20 sides of the adenovirus form what

12 vertices

11

What extends from each vertice

binding protein spike fibers

12

Are adenoviruses enveloped or non-enveloped

non-enveloped

13

How many serotypes does the adenovirus have

49 serotypes

14

What is the largest of non-enveloped viruses

adenovirus

15

Each type of serotype infects what

only 1 type of species

16

Why do upper repiratory typically go unreported

they are minor symptoms similiar to the common cold

17

Why is the adenovirus good for gene therapy

It has a DNA genome which replicates in the nucleus of the cell where the human genome is

18

How does the adenovirus get entry into the cell

protein spikes bind to receptor on cell surface and the virus in endocytosed

19

what occurs directly after the adenovirus enters the cell

the virion is released and the viral genome enters the nucleus

20

What type of genome does the adenovirus have

ds DNA

21

How many base pairs does the adenovirus have

38kb

22

How many genes does the adenovirus code for

30 genes

23

What is the first step of the adenovirus replication

early genes are transcribed first and spliced into individual mRNAs

24

What are the early genes transcribed from

9 promoters

25

How many non-structural proteins are translated

12

26

What are the functions of early genes

regulatory enzymes
-upregulate expression of host cells DNA replication machinery
-activate other viral genes
-inhibit cell death

27

Why are early genes typically involved in regulatory while late genes are structural

-a necessary order
-efficiency issue (what needs to happen to drive replication process and then express the structural proteins from the replicated genomes

28

What is the second step of adenovirus replication

DNA replication

29

What type of polymerase is used for DNA replication

virus expressed DNA polymerase

30

What is the third step of adenovirus replication

late genes are expressed

31

What is the fourth step of adenovirus replication

assembly

32

where does assembly occur

in the nucleus

33

What is the fifth step of adenovirus replication

release

34

What happens to the cell in order for release of the virus

transcription and translation shut down and the cell dies

35

What serotypes cause disease in early childhool

1,2

36

What serotype causes disease later in life

3,5

37

What are adenovirus infection symptoms

"stuffy nose" and cough
pharyngitis
pneumonia
GI infection

38

What serotypes cause pneumonia

3,7

39

What serotypes cause GI infection

40,41

40

What serotypes cause pharyngoconjunctival fever

3,4,7

41

What is pharyngoconjunctival fever typically associated with

swimming pools

42

How is the virus transmitted

aerosol, direct contact, fecal-oral

43

What are some characteristics of the adenovirus

can resist pH and chemical stresses

44

What is the vaccine for adenovirus

there is none

45

What does corona mean

latin for crown

46

what percentage of common colds do coronoviruses account for

2-10%

47

What is the diameter of corona virus

60-220

48

Is the corona virus enveloped or not

enveloped

49

What is the capsid shape of the coronavirus

helical

50

Why is this shape weird for the corona virus

because its unusual for a + stranded virus

51

What comes off the surface of the coronavirus

large dub-shaped protein spikes

52

How many serotypes of the corona virus infect humans

3

53

how many serotypes of the corona virus infect other animals

15

54

What type of genome does the corona virus have

ss RNA positive

55

how many base pairs does the corona virus have

30kb

56

What is the largest RNA virus infecting humans

coronavirus

57

What are the 5 main proteins of the genome

R1/2, S, HE, M, N

58

What is the R1/R2 protein

replicase

59

What is the S protein

surface trimer

60

What is the HE protein

virus exit

61

What is the M protein

structural membrane protein

62

What is the N protein

nucleocapsid protein

63

How does the corona virus gain entry to the cell

attaches to host cell through S spike proteins, virus is endocytosed into the cell

64

Where does viral replication occur for corona virus

cytoplasm

65

How is the corona virus replicated

directly translated into 2 polyproteins that are cleaved into 16 smaller proteins

66

What type of replicase is used

RNA polymerase

67

What does the replicase do

transcribes a full length RNA strand (negative)

68

What does the negative strand serve as

transcribed to make positive strands, yield many smaller mRNAs which are translated into smaller proteins

69

What is the RNA polymerase prone to

errors

70

What is the ratio for errors

1/10000 nucleotides

71

What does the high rate of recombination between RNA strands equal

rapid change in virus host range and disease

72

Where does assembly of the corona virus occur

in cytoplasm

73

How does assembly occur

virions bud from the RER, virions accumulate in the Golgi and are released when vesicles leave the golgi and fuse with plasma membrane

74

What is the incubation period for corona virus

3 days

75

where is the corona virus confined to in the body

upper respiratory tract

76

What are the symptoms of the corona virus

nasal discharge, malaise, no fever, no coughing, no sore throat

77

How long do the symptoms last

1 week

78

When do epidemics of the corona virus occur

winter and early spring

79

Why are reinfections common

due to poor immune response

80

What does SARS stand for

severe acute respiratory syndrome

81

When did the SARS virus emerge

in NOV 2002 in China

82

How did the US get the SARS virus

us businessman traveled from China and dies

83

What type of virus was SARS

coronavirus

84

How many open reading frames did SARS have

11

85

how many proteins were coded for

23

86

What were the main proteins coded for

S,M,N (no HE)

87

How is the virus replicated

into 2 large polypeptides and then cleaved

88

Incubation period for SARS

4-5 days

89

What is the first symptom of SARS

high fever

90

What are symptoms of SARS

high fever, diarrhea, dry cough, pneumonia

91

How long til symptoms peak

7-8 days

92

How is SARS transmitted

respiratory droplets, direct contact

93

What is the R0 for SARS

2

94

How many US cases of SARS

8

95

Where did SARS come from

chinese horseshoe bat

96

What does Rhinos mean

greek for nose

97

What is the diameter of rhinos

18-30nm

98

Is the rhinovirus enveloped or non-enveloped

non-enveloped

99

What is the capsid shape

icosohedral

100

What is the genome of the rhinovirus

ss-RNA positive

101

how many base pairs for Rhinovirus

7-8kb

102

How many serotypes of the rhinovirus

100

103

How does the rhinovirus relate to pH

can't withstand low

104

What temperatures do rhinoviruses prefer

low

105

How is the rhinovirus translated

into large polypeptide and then is cleaved into smaller functional proteins

106

What cellularly does the Rhinovirus shut down

translation of cellular mRNA, leads to cell death

107

What does cell death entail

new virions released

108

What is disease

common cold

109

What is the incubation period for rhinovirus

2-3 days

110

What are the symptoms of rhinovirus

nasal congestion
cough
sneezing
sore throat
NO FEVER

111

How is the rhinovirus transmitted

aerosol
direct contact
surfaces of cups and plates

112

Why is curing the common cold difficult

large number of serotypes

113

What are the 4 paramyxoviruses

measles, mumps, RSV, parainfluenza

114

What do paramyxoviruses cause

predominantly respiratory tract diseasee

115

What are paramyxoviruses responsible for

1/2 of all cases of croup, bronchiolitis, and pneumonia in infants

116

What does paramyxoviruses cause to the cells

fusion

117

fusion leads to what

synctia

118

what is synctia

giant multinucleated cells

119

How is paramyxoviridae transmitted

respiratory droplets or direct contact

120

are paramyxoviridae enveloped or non-enveloped

enveloped

121

What type of genome does paramyxoviridae have

RNA negative

122

What size is the paramyxoviridae diameter

150-200

123

What shape of capsid does the paramyxoviridae virus have

helical

124

What are the two surface proteins of the paramyxoviritade

HN and F

125

What is HN protein

hemagluttinin-neuraminidase

126

What is F protein

fusion protein, translated as a larger precursor protein

127

What is the internal structural protein

M protin (matrix)

128

How are protein involved with the nucleoprotein core

proteins plus RNA genome

129

How many bases is the paramyxoviridae genome

15kb

130

how many genes approximately are coded for by the paramyxoviridae genome

10 genes

131

Where does replication occur for the paramyxoviridae

cytoplasm

132

What is the genome transcribed by

transciptase single mRNAs for each gene

133

the nucleoprotein interacts with M protein to form what

nucleocapsid

134

newly synthesized genomes interact with transcriptase and other proteins to form what

nucleoprotein

135

Once assembly is complete what happens

virions bud off from surface of host cell

136

What is it called when virions spread from cell to cell by fusion

creepers

137

What is one of the most highly infectious viruses

Measles

138

How is the infection in temperate countries

mild, serious complications are rare

139

How is the infection in tropical countries

serious problem, large scale killer of children

140

What type of infection is measles

acute, generalized

141

What type of incubation period does measles have

long period

142

What is the time frame from infection to rash

2 weeks

143

What is the first stage of the measles

prodromal stage (prior to symptoms)

144

How long does the prodromal stage last

2-3 days

145

What symptoms occur durring prodromal stage

running nose, watery eyes, cough, moderate fever, Koplik spots appear

146

What is the second stage of measles

rash stage

147

What causes the rash

CTLs recognizing viral antigen on skin cells

148

Why is the rash a good sign

shows immune system is working

149

What is a characteristic/ diagnostic appearance for measles

red, blotchy

150

What is the third stage of measles

immune response

151

What occurs during the immune response

IgMs and IgG and CTL memory

152

When is the virus shed

acute stage and prodromal

153

What are three complications of measles

bronchitis
pneumonia
encephalitis

154

What is the vaccine for measles

MMR

155

What does MMR protect against

measles, mumps, rubella

156

how many serotypes of measles

1

157

In developing countries, who does measles affect most

children younger than 2

158

How many children die each year form measles

1 million

159

Why are symptoms more severe in developing countries

younger age and malnutrition

160

Why does Vitamin A deficiency affect survival

leads to corneal ulcers and blindness

161

What is the mortality rate of measles

10%

162

Why is it difficult to innoculate against measles

vaccine must be kept cold until just before use

163

What does RSV stand for

respiratory synctial virus

164

When do outbreaks of RSV typically occur

december

165

who does RSV typically affect

elderly and infants

166

RSV is what in regards to spreading

highly contagious

167

What is the incubation period for RSV

5 days

168

How does RSV start

as a common cold

169

How do infants react to RSV

become acutely ill in 24 hours with repiratory distress and cyanosis (blue fingers, lips, and toes)

170

What are symptoms of RSV

bronchiolitis with or without pneumonia, long term respiratory problems, severe illness and maybe death

171

How early can infants be infected with RSV

as early as 6 weeks

172

What does the early infection of infants mean

indicates mother's antibodies do not protect for long

173

What responses does RSV induce, but still little response

antibody and CMI

174

How many serotypes of RSV

2

175

Why doesn't RSV trigger much of an immune response

it doesn't use interferons

176

When can the virus be shed

for 3 weeks after acute phase of infection

177

How is transmitting the RSV virus

respiratory secretions, temperate climates, tropics

178

What is the vaccine for RSV

there is non

179

For high risk infants what can be used in emergencies

human antibodies

180

What has been effective against RSV

RNAi

181

What is the incubation period for mumps

2-3 weeks

182

Who does mumps typically affect

those less than 15 years old

183

What are symptoms of mumps

malaise, fever, enlargement of paratid glands, orchitis

184

How is mumps transmitted

spread by respiratory aerosol or hand contact

185

how long is mumps shed period

for several days before and after the 1st symptoms

186

What is the vaccine for mumps

MMR vaccine

187

How long is mumps immunity with vaccine

20 years

188

What does the parainfluenza virus cause

1/3 of all respiratory tract infections and nearly 1/2 of respiratory infections in children and infants

189

What are the 4 types of the parainfluenza virus

types 1,2
type 3
type 4

190

What does types 1,2 cause

croup (more in boys than girls)

191

What does type 3 cause

lower respiratory tract illness

192

What does type 4 cause

less severe disease

193

What is the vaccine for parainfluenza virus

none