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piggy > Micro - Virology Part 1 > Flashcards

Micro - Virology Part 1 Flashcards

1
Q

A recent renal transplant recipient has fever, malaise, allograft dysfunction, and cells with “owl’s eye” inclusions. Diagnosis?

A

CMV infection

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2
Q

What are the two components of the naked icosahedral virus structure?

A

Nucleocapsid and nucleic acid

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3
Q

What are the four components of an enveloped icosahedral virus structure?

A

Surface protein, lipid bilayer, capsid, and nucleic acid

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4
Q

What are the four components of the enveloped helical virus structure?

A

Surface protein; matrix or core protein; lipid bilayer; and nucleic acid and
nucleocapsid protein

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5
Q

Structurally, what are the three main classes of viruses?

A

Naked icosahedral, enveloped icosahedreal, enveloped helical

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6
Q

In viral genetics, what is recombination?

A

It is the exchange of genes between two chromosomes by crossing over within
regions of significant base sequence homology

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7
Q

In viral genetics, what is reassortment?

A

It is the exchange of segments among viruses with segmented genomes (eg,
influenza virus)

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8
Q

Which type of viral genetic event can cause worldwide pandemics?

A

Reassortment, which happens when viruses with segmented genomes (eg,
influenza virus) exchange segments

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9
Q

In viral genetics, when does complementation occur?

A

Complementation occurs when one of two viruses that infect the cell has a mutation that results in a nonfunctional protein and the nonmutated virus makes a functional protein that serves both viruses (the nonmutated virus “complements” the mutated one)

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10
Q

In viral genetics, when does phenotype mixing occur?

A

Phenotype mixing occurs when the genome of virus A is coated with the surface
proteins of virus B and infectivity is determined by the virus B protein coat, but the
progeny is encoded by virus A generic material and will have the virus A coat

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11
Q

Viral genome reassortment occurs in viruses with what type of genomic structure?

A

Segmented genomes

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12
Q

What is a pseudovirion?

A

The genetic material of one virus coated by the surface proteins of a different virus

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13
Q

What is the difference between the immunity induced by a live, attenuated virus
and that of killed virus vaccines?

A

Live, attenuated vaccines induce humoral and cell-mediated immunity whereas
killed vaccines induce only humoral immunity

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14
Q

What is the advantage of killed vaccines over live, attenuated vaccines?

A

Killed vaccines are more stable, whereas live, attenuated vaccines have reverted to
virulence on very rare occasions

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15
Q

Live vaccines are dangerous to give to which populations?

A

Immunocompromised patients or their contacts

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16
Q

Name five live, attenuated vaccines.

A

MMR (measles, mumps, rubella), Sabin polio, varicella zoster virus, yellow fever,
smallpox (remember: “Live! One night only! See small yellow chickens get
vaccinated with Sabins and MMR”)

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17
Q

Name four killed virus vaccines.

A

Rabies, Influenza, Salk Polio, and hepatitis A virus (remember: RIP Always, and
SalK= Killed)

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18
Q

Name two recombinant vaccines.

A

Hepatitis B virus and human papilloma virus vaccines

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19
Q

What is the antigen that is present in the hepatitis B virus vaccine?

A

Recombinant hepatitis B surface antigen

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20
Q

Which human papillomavirus types does the human papillomavirus vaccine protect
against?

A

Types 6, 11, 16, and 18; the types most likely to cause cervical cancer and genital
warts

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21
Q

What is the only live, attenuated vaccine that can be given to HIV-positive
individuals?

A

MMR (measles, mumps, rubella)

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22
Q

All DNA viruses contain double-stranded DNA, except for which family?

A

Parvoviridae, which has single-stranded DNA (remember: part-of-a-virus)

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23
Q

Which three DNA viruses contain nonlinear DNA?

A

Papilloma, polyoma, and hepadna viruses, which contain circular DNA

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24
Q

All RNA viruses contain single-stranded RNA, except for which family?

A

Reoviridae (remember: all are single-strand RNA except “repeatovirus” [reovirus]
is double-stranded RNA])

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25
Q

Purified nucleic acids from which viruses are considered infectious?

A

Most double-stranded DNA viruses and positive-strand single-stranded RNA
viruses

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26
Q

Why are negative-strand single-stranded RNA and double-stranded RNA viruses
not infectious?

A

They require enzymes found in the complete virion to become infectious

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27
Q

The purified nucleic acids of what two double-stranded DNA viruses are not
considered infectious?

A

Poxviruses and hepatitis B virus; both require enzymes not found in human cells
for replication

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28
Q

Are most viruses haploid or diploid?

A

Most are haploid (one copy of genetic material)

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29
Q

What is the only virus that is not haploid?

A

Retroviruses (2 copies of single-stranded RNA)

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30
Q

With one exception, all DNA viruses replicate in what part of the host cell?

A

Nucleus

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31
Q

All DNA viruses replicate in the nucleus of the host cell, except for which virus?

A

Poxvirus

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32
Q

Do most RNA viruses replicate in the cytoplasm or the nucleus of the host cell?

A

Cytoplasm

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33
Q

Which two RNA viruses replicate in the host cell nucleus?

A

The influenza virus and retroviruses

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34
Q

What are the seven naked (nonenveloped) viruses?

A 
Calicivirus, Picornavirus, Reovirus, Parvovirus, Adenovirus, Papillomavirus, 
and Polyomavirus (remember: naked CPR and PAPP smear)
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35
Q

From what structure are most viral envelopes derived?

A

Plasma membrane

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36
Q

The herpesviruses acquire their envelopes from which component of the host cell?

A

Nuclear membrane

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37
Q

Name three enveloped DNA viruses.

A

Herpesviruses, hepatitis B virus, smallpox virus

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38
Q

Herpesviruses are _____ (DNA/RNA) _____ (enveloped/nucleocapsid) viruses.

A

DNA; enveloped

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39
Q

Hepatitis B is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

DNA; enveloped

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40
Q

Smallpox is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

DNA; enveloped

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41
Q

Name three DNA nucleocapsid viruses.

A

Adenovirus, papillomaviruses, parvovirus

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42
Q

Adenovirus is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

DNA; nucleocapsid

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43
Q

Papillomavirus is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

DNA; nucleocapsid

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44
Q

Parvovirus is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

DNA; nucleocapsid

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45
Q

Influenza virus is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

RNA; enveloped

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46
Q

Parainfluenza is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

RNA; enveloped

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47
Q

Respiratory syncytial virus is a _____ (DNA/RNA) _____

(enveloped/nucleocapsid) virus.

A

RNA; enveloped

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48
Q

Measles virus is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

RNA; enveloped

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49
Q

Mumps virus is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

RNA; enveloped

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50
Q

Rubella virus is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

RNA; enveloped

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51
Q

Rabies is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

RNA; enveloped

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52
Q

Human T-lymphotropic virus is a _____ (DNA/RNA) _____

(enveloped/nucleocapsid) virus.

A

RNA; enveloped

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53
Q

HIV is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

RNA; enveloped

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54
Q

Enteroviruses are _____ (DNA/RNA) _____ (enveloped/nucleocapsid) viruses.

A

RNA; nucleocapsid

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55
Q

Rhinovirus is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid) virus.

A

RNA; nucleocapsid

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56
Q

Reovirus (rotavirus) is a _____ (DNA/RNA) _____ (enveloped/nucleocapsid)
virus.

A

RNA; nucleocapsid

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57
Q

Name the three types of RNA nucleocapsid viruses.

A

Enteroviruses, rhinovirus, and reovirus (rotavirus)

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58
Q

Name the seven DNA viruses.

A 
Hepadnavirus, Herpesvirus, Adenovirus, Poxvirus, Parvovirus, Papillomavirus, 
and Polyomavirus (remember the mnemonic: HHAPPPPy viruses)
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59
Q

All DNA viruses are linear except what three DNA viruses?

A

Hepadnavirus (circular, incomplete) and papillomavirus/polyomavirus (circular,
supercoiled)

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60
Q

All DNA viruses are icosahedral except which one?

A

Poxvirus; it is complex

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61
Q

Which DNA virus does not replicate in the nucleus?

A

Poxvirus; it has a DNA-dependent RNA polymerase and can replicate without nuclear enzymes

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62
Q

In general, DNA viruses are _____ (single/double) stranded, _____
(linear/circular), icosahedral, and replicate in the _____ (nucleus/cytoplasm).

A

Double stranded; linear; nucleus

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63
Q

Name seven medically important herpesviruses.

A

Herpes simplex virus type 1, herpes simplex virus type 2, varicella zoster virus,
Epstein-Barr virus, cytomegalovirus, human herpesvirus type 6, and human
herpesvirus type 8 (human herpesvirus 7 is not clinically significant)

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64
Q

Which herpesvirus most often causes oral lesions as well as keratoconjunctivitis?

A

Herpes simplex virus type 1

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65
Q

Which herpesvirus most often causes genital lesions in humans?

A

Herpes simplex virus type 2

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66
Q

Chickenpox, zoster, and shingles are caused by what DNA virus?

A

Varicella zoster virus

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67
Q

Which types of patients are particularly vulnerable to significant cytomegalovirus infection?

A

Immunosuppressed patients (especially transplant recipients) and the fetuses of infected mothers

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68
Q

Which childhood illness is caused by human herpesvirus type 6?

A

Roseola (exanthem subitum)

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69
Q

Which DNA virus is associated with Kaposi sarcoma?

A

Human herpesvirus type 8 (Kaposi’s sarcoma-associated herpesvirus)

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70
Q

To what viral family does hepatitis B virus belong?

A

Hepadnavirus

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71
Q

Which enzyme does hepatitis B virus have in common with retrovirus?

A

Reverse transcriptase

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72
Q

Adenovirus is most commonly responsible for what three conditions?

A

Febrile pharyngitis (sore throat), pneumonia, and conjunctivitis

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73
Q

What is the smallest DNA virus?

A

Parvovirus

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74
Q

What skin exanthem does parvovirus B19 cause in children?

A

Erythema infectiosum (“slapped-cheek” rash)

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75
Q

Parvovirus B19 causes what condition in patients with sickle cell disease?

A

Aplastic crisis

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76
Q

What severe complication is seen in the fetuses of pregnant women who are
exposed to parvovirus B19?

A

Hydrops fetalis (due to red blood cell destruction)

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77
Q

What two DNA virus families were originally categorized together as
papovavirus?

A

Papillomavirus and polyomavirus

78
Q

What type of disease does papillomavirus cause?

A

Genital warts, cervical intraepithelial neoplasia, and cervical cancer

79
Q

JC virus is the causative agent of what condition in HIV-positive patients?

A

Progressive multifocal leukoencephalopathy

80
Q

Which viral family is responsible for smallpox, cowpox, and molluscum
contagiosum?

A

Poxvirus

81
Q

What is the largest DNA virus?

A

Poxvirus

82
Q

Which disease caused by a poxvirus has been eradicated but could possibly be used
in germ warfare?

A

Smallpox

83
Q

Vaccinia virus causes what condition?

A

Cowpox (“milkmaids blisters”)

84
Q

Which is the only hepatitis-causing virus that is a DNA virus?

A

Hepatitis B virus

85
Q

Name six medically important herpesviruses.

A

Cytomegalovirus, Herpes simplex virus types 1 and 2, Human herpesvirus type
8, Epstein-Barr virus, Varicella zoster virus (remember: get herpes in
a CHEVrolet)

86
Q

Which herpesvirus causes gingivostomatitis, keratoconjunctivitis, temporal lobe
encephalitis, and herpes labialis?

A

Herpes simplex virus type 1

87
Q

Herpes encephalitis usually affects which lobe of the brain?

A

The temporal lobe

88
Q

Herpes genitalis and neonatal herpes are most commonly caused by what herpes virus?

A

Herpes simplex virus type 2

89
Q

Shingles, encephalitis and pneumonia can be caused by which herpesvirus?

A

Varicella zoster virus

90
Q

Epstein-Barr virus causes what conditions?

A

Infectious mononucleosis, Burkitts lymphoma and nasopharyngeal carcinoma

91
Q

Cytomegalovirus causes what conditions?

A

Congenital infection, mononucleosis, and pneumonia

92
Q

What is the most likely etiology for a mononucleosis-like presentation that is
monospot test negative?

A

Cytomegalovirus

93
Q

Human herpesvirus type 8 can cause what disease in HIV-positive patients?

A

Kaposi sarcoma

94
Q

What is the primary route of transmission of herpes simplex virus type 1?

A

Respiratory secretions and saliva

95
Q

How is herpes simplex virus type 2 primarily transmitted?

A

Via sexual contact and perinatally

96
Q

How is varicella zoster virus transmitted?

A

Respiratory secretions

97
Q

What are the modes of cytomegalovirus transmission?

A

Congenital, transfusion, sexual contact, saliva, urine, and organ transplantation

98
Q

Human herpesvirus type 8 is primarily transmitted via what route?

A

Sexual contact

99
Q

What histologic finding is characteristic of cells infected with cytomegalovirus?

A

“Owls eye” intranuclear inclusions

100
Q

How is Epstein-Barr virus transmitted?

A

Respiratory secretions and saliva

101
Q

Where does varicella zoster virus remain dormant in the body after primary
infection?

A

In the dorsal root and trigeminal ganglia

102
Q

Describe the clinical presentation of human herpesvirus type 6 infection.

A

Roseola: high fevers followed by a diffuse macular rash; human herpesvirus type 6
is one of the most common causes of febrile seizures in children

103
Q

What is the Tzanck test?

A

A test to detect multinucleated giant cells in opened skin vesicles of herpes simplex
virus type 1 and 2 and varicella zoster virus

104
Q

HSV-infected cells contain inclusion bodies known as what?

A

Cowdry A intranuclear inclusions

105
Q

Which herpesvirus is the most common cause of mononucleosis?

A

Epstein-Barr virus

106
Q

Epstein-Barr virus causes mononucleosis by infecting which cells?

A

B cells

107
Q

A college student presents to the emergency department with fever,
hepatosplenomegaly, pharyngitis and lymphadenopathy (especially posterior
cervical nodes). Which viral infection should be suspected?

A

Epstein-Barr virus can cause mononucleosis, also known as the “kissing disease”
because its peak incidence is 15-20 years old (peak “kissing years”); transmission
is through saliva

108
Q

What laboratory test can be used to diagnose mononucleosis?

A

Monospot test: heterophil antibodies detected by agglutination of sheep red blood cells

109
Q

A complete blood count of a patient with infectious mononucleosis would show
what abnormalities?

A

Atypical lymphocytes (circulating cytotoxic T cells)

110
Q

Epstein-Barr virus is associated with the development of which three types of
malignancy?

A

Hodgkins and endemic Burkitts lymphoma and nasopharyngeal carcinoma

111
Q

What vaccines exist against poliovirus?

A

Salk (inactivated polio vaccine) and Sabin (oral polio vaccine)

112
Q

Which two picornaviruses commonly cause aseptic meningitis?

A

Echovirus and coxsackievirus

113
Q

Which two RNA viruses cause the common cold?

A

Rhinovirus and coronavirus

114
Q

Aseptic meningitis; myocarditis; herpangina; and hand, foot, and mouth disease are
caused by which picornavirus?

A

Coxsackieviruses

115
Q

Name a medically important calicivirus.

A

Norwalk virus

116
Q

Norwalk virus causes what condition?

A

Viral gastroenteritis

117
Q

Rotavirus belongs to which viral family?

A

Reoviruses

118
Q

Reovirus causes what condition?

A

Colorado tick fever

119
Q

The structure of the genome of reovirus is unique among RNA viruses in what
respect?

A

It has double-stranded RNA with 10-12 strands, whereas all other RNA viruses are
single stranded

120
Q

Flaviviruses are responsible for what five diseases?

A

Hepatitis C virus, yellow fever, dengue, St. Louis encephalitis, and West Nile virus

121
Q

Togaviruses cause what three diseases?

A

Rubella (German measles), Eastern equine encephalitis, and Western equine
encephalitis

122
Q

Name two RNA viruses that have reverse transcriptase.

A

HIV (a retrovirus), and human T-lymphotropic virus

123
Q

Human T-lymphotropic virus causes what disease?

A

T-lymphocyte leukemia

124
Q

Coronaviruses are the causative agents of what two diseases?

A

The common cold and severe acute respiratory syndrome (SARS)

125
Q

Which medically important RNA virus belongs to the orthomyxovirus family?

A

Influenza

126
Q

Name four medically important paramyxoviruses.

A

Parainfluenza, Respiratory syncytial virus, Measles (rubeola), and Mumps;
remember: PaRaMyxoviruses

127
Q

What disease does parainfluenza virus cause?

A

Croup

128
Q

What disease does respiratory syncytial virus cause in babies?

A

Bronchiolitis

129
Q

Rabies virus is what type of virus?

A

Rhabdovirus

130
Q

Filoviruses are the causative agents of what two diseases?

A

Ebola hemorrhagic fever and Marburg hemorrhagic fever; both are frequently fatal

131
Q

Arenaviruses are the causative agents of what two diseases?

A

Lymphocytic choriomeningitis and Lassa fever encephalitis

132
Q

Bunyaviruses are the causative agents of what four diseases?

A

California encephalitis, Sandfly/Rift Valley fevers, Crimean-Congo hemorrhagic
fever and hantavirus

133
Q

Hepatitis D virus belongs to which viral family?

A

Deltavirus

134
Q

The viruses that cause viral hepatitis A-E in humans belong to which families?

A

Picornavirus (hepatitis A), hepadnavirus (hepatitis B), flavivirus (hepatitis C),
deltavirus (hepatitis D), hepevirus (hepatitis E)

135
Q

Name six viral families that are single-strand, positive-sense, linear RNA viruses
with icosahedral capsids.

A

Picornavirus, hepevirus, calicivirus, flavivirus, togavirus, and retrovirus

136
Q

Name the viral family that is made up of double-stranded RNA viruses with a
double icosahedral capsid.

A

Reovirus

137
Q

All negative-sense RNA viruses have what type of capsid?

A

Helical

138
Q

Which clinically significant virus has a segmented linear RNA?

A

Influenza (an orthomyxovirus)

139
Q

What are the three viral families with circular RNA?

A

Arenaviruses, bunyaviruses, and deltavirus

140
Q

What is the only positive-sense RNA virus with a helical capsid?

A

Coronavirus

141
Q

True or False? All helical viruses are enveloped.

A

True

142
Q

Which diseases are caused by arboviruses?

A

Yellow fever, dengue, St. Louis encephalitis, West Nile virus, Eastern equine
encephalitis and Western equine encephalitis, California encephalitis, Crimean-
Congo hemorrhagic fever

143
Q

Name the four families of RNA viruses that have no envelope.

A

Reoviruses, picornaviruses, hepevirus and caliciviruses

144
Q

What must a negative-stranded DNA virus do to replicate within a human cell?

A

Transcribe its negative strand to a positive strand; it does this by carrying an RNA-
dependent RNA polymerase

145
Q

Name the six negative-stranded virus families.

A 
Arenaviruses, Bunyaviruses, Paramyxoviruses, Orthomyxoviruses, Filoviruses, 
and Rhabdoviruses (remember: Always Bring Polymerase Or Fail Replication)
146
Q

All segmented viruses are ____ (RNA/DNA) viruses.

A

RNA

147
Q

Name four segmented RNA viruses.

A

Bunyaviruses, Orthomyxoviruses (influenza), Arenaviruses, and Reoviruses
(remember: BOAR)

148
Q

How many segments of RNA make up the influenza virus genome?

A

Eight

149
Q

The reassortment of influenza virus RNA segments results in antigenic _____
(shift/drift) and is a cause of _____ (pandemics/epidemics).

A

Shift; pandemics

150
Q

What five RNA viruses are picornaviruses?

A

Poliovirus, Echovirus, Rhinovirus, Coxsackievirus, and Hepatitis A virus
(remember: PERCH on a “peak” = Pico)

151
Q

Picornaviruses (except rhinovirus and hepatitis A virus) can cause what condition
in humans?

A

Aseptic meningitis

152
Q

Picornaviruses are (small/large) _____, (RNA/DNA) _____ viruses.

A

Small, RNA (remember: PicoRNAvirus = RNA virus)

153
Q

What type of virus is rhinovirus?

A

A nonenveloped RNA virus that belongs to the picornavirus family

154
Q

Why are humans susceptible to multiple recurrent infections with rhinovirus
causing cold-like symptoms?

A

Because there are more than 100 serologic types of rhinovirus

155
Q

Yellow fever is caused by a virus that belongs to what viral family?

A

Flavivirus, which is an arbovirus (flavi = yellow)

156
Q

How is yellow fever transmitted?

A

By Aedes mosquitoes

157
Q

A 30-year-old man presents to the emergency room with a high fever, black
vomitus, and a yellow discoloration to his skin. What is the most likely etiology?

A

Yellow fever

158
Q

What histologic finding on liver biopsy is seen in patients with yellow fever?

A

Councilman bodies (acidophilic inclusion bodies)

159
Q

Globally, what is the most important cause of infantile gastroenteritis?

A

Rotavirus

160
Q

During what season is rotavirus the major cause of acute diarrhea in the United
States?

A

Winter, although a new vaccine is significantly reducing cases of rotavirus

161
Q

What is the pathophysiology of the diarrhea caused by rotavirus?

A

Atrophy and destruction of intestinal villi lead to decreased absorption of sodium
and water; remember: ROTA = Right Out The Anus

162
Q

In what settings are rotavirus diarrhea commonly seen?

A

Daycare centers and kindergartens

163
Q

Influenza virus is _____ (enveloped/nonenveloped), with _____-_____ (single-
stranded/double-stranded), _____ (segmented/nonsegmented) RNA.

A

Enveloped; single-stranded; segmented

164
Q

Name the two major antigens of the influenza virus.

A

Hemagglutinin and neuraminidase

165
Q

If influenza results in fatal illness, which complication is usually responsible?

A

Pneumonia caused by bacterial superinfection

166
Q

What is the major mode of protection against influenza virus?

A

Killed virus vaccine; the vaccine is reformulated each year

167
Q

What are the functions of hemagglutinin and neuraminidase?

A

Hemagglutinin promotes viral entry and neuraminidase promotes the release of
viral progeny

168
Q

The recombination of human flu A virus with swine flu A virus is an example of
what?

A

Genetic shift, the reassortment of viral genome, which can cause worldwide
pandemics

169
Q

Random mutations leading to minor genetic changes in the human flu A virus is an
example of what?

A

Genetic drift (antigenic drift)

170
Q

Genetic shift causes (epidemics/pandemics) _____ while genetic drift causes
(epidemics/pandemics) _____.

A

Pandemics, epidemics; remember: Sudden Shift is more deadly than graDual Drift

171
Q

An unvaccinated 4-year-old boy presents with fever, lymphadenopathy, arthralgias
and a fine truncal rash. The rash persists for only 3 days. Which viral infection
should be suspected?

A

Rubella

172
Q

Rubella is a relatively benign illness in most cases, but when can serious sequelae
result?

A

When it infects fetuses (it is one of the T0RCH infections)

173
Q

What diseases are caused by paramyxoviruses?

A

Mumps, measles, croup and respiratory syncytial virus bronchiolitis

174
Q

Paramyxoviruses cause disease predominantly in what age group?

A

Children

175
Q

What is the typical clinical presentation of croup?

A

A seal-like barking cough

176
Q

What surface protein is common to all paramyxoviruses? What is its role?

A 
Surface F (fusion) protein, which causes respiratory epithelial cells to fuse and 
form multinucleated cells
177
Q

Injections of which monoclonal antibody are given to children at high risk of
severe respiratory syncytial virus bronchiolitis?

A

Palivizumab

178
Q

Describe the progression of disease in rabies.

A

It begins with fever and malaise, develops into agitation, hydrophobia,
photophobia, and then paralysis, coma, and death

179
Q

How does rabies virus invade the central nervous system?

A

By migrating in a retrograde fashion up the nerve axons

180
Q

What animal bites are most likely to result in rabies infection in the United States?

A

Bat, raccoon, and skunk bites

181
Q

What is the importance of postexposure vaccination in rabies?

A

The disease is universally fatal after symptoms have developed

182
Q

What are arboviruses?

A

Viruses transmitted by arthropods (remember: ARBOvirus: ARthropod-BOrne
virus)

183
Q

Arboviruses include members of which viral families?

A

Flavivirus, Togavirus, and Bunyavirus (remember: Fever Transmitted by Bites)

184
Q

The hepatitis A virus is primarily transmitted via what route?

A

The fecal-oral route

185
Q

The hepatitis E virus is primarily transmitted via what route?

A

The enteric route (causing water-borne epidemics)

186
Q

The clinical course of hepatitis E infection resembles that of what other hepatitis
virus?

A

Hepatitis A

187
Q

How is the hepatitis E virus different from the hepatitis A virus?

A

The hepatitis E virus can cause waterborne epidemics and has a high mortality rate
among pregnant women (remember: Hep E: Enteric, Expectant
mothers, Epidemics)

188
Q

How does the number of people with serologic evidence of prior hepatitis A
infection compare to the number who have had clinically significant infection?

A

Most infections are clinically insignificant (remember:

Hep A: Asymptomatic, Acute, Alone [no carriers])

189
Q

Does hepatitis A virus have a short or long incubation period?

A

Short (3 weeks); there are no chronic carriers of the infection

190
Q

How is the hepatitis B virus transmitted?

A

By parenteral, sexual, or maternal-fetal routes (remember: Hepatitis B: Blood
borne)

191
Q

Which hepatitis virus has a reverse transcription capability?

A

Hepatitis B virus; reverse transcription occurs (DNA from an RNA
intermediate) but the virion enzyme is a DNA-dependent DNA polymerase

piggy (83 decks)

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