Microbiology For Medschool Exam 3- Virology

Front 1

A virus is the size of a eukaryotic _________?

Back 1

ribosome

Front 2

Virus with envelope in environment?

Back 2

inactivated, must be in aqueous environment, like blood, saliva, other body fluids

Front 3

Virus without envelopes (naked) in environment?

Back 3

stable, can survive for months

Front 4

Why are enveloped viruses unstable?

Back 4

envelope sticks to surfaces, clothing, viral structure destroyed

Front 5

Where does the viral envelope come from?

Back 5

host cell plasma membrane

Front 6

Viral envelope can be destroyed by?

Back 6

organic solvents like ether (chloroform), bile salts in GI tract

Front 7

Peplomers?

Back 7

transmembrane protein spikes

Front 8

Viruses can only replicate where?

Back 8

in host, never in test tube

Front 9

Helical viruses always have what?

Back 9

an envelope

Front 10

DNA viruses must?

Back 10

go to host nucleus, need DNA polymerase to replicate

Front 11

RNA viruses can replicate in?

Back 11

cytoplasm, have own polymerase

Front 12

All DNA viruses replicate in nucleus except?

Back 12

Poxvirus (smallpox)

Front 13

Viruses only make what kind of RNA?

Back 13

mRNA, not tRNA or rRNA

Front 14

Steps to DNA virus infection (4)?

Back 14

1) virus goes to host, 2) uses viral DNA polymerase to replicate 3) uses host DNA dependent DNA polymerase II to make viral mRNA 4) host ribosomes make viral proteins

Front 15

Drugs for DNA viruses target?

Back 15

Viral DNA polymerase, not host DNA polymerase

Front 16

Steps in RNA virus infection (3)?

Back 16

1)make RNA dependent RNA polymerase (RdRp) 2)RdRp makes mRNA 3)host ribosomes translate mRNA to viral protein

Front 17

Steps in Retroviral infection (3)?

Back 17

1) virus uses viral RNA dependent DNA polymerase to make DNA 2) DNA is transcribed with DNA dependent RNA polymerase II from host to make mRNA 3) host ribosomes translate mRNA to viral protein

Front 18

Steps in virus life cycle (5)?

Back 18

1- attach to cell, 2- genome replication and RNA synthesis, 3- make capsid proteins for RNA, 4- nucleocapsid assembly, 5- release of viral particles from host cell

Front 19

Most viruses have what type of genome?

Back 19

single stranded RNA

Front 20

mRNA must have 1 or more what?

Back 20

ORF (open reading frame)

Front 21

Viruses must make proteins at least how long?

Back 21

20 amino acids long

Front 22

mRNA can make protein, called?

Back 22

(+) sense

Front 23

No ORF, no protein made, called?

Back 23

(-) sense

Front 24

First step in (+) sense RNA virus infection?

Back 24

translation!

Front 25

Steps in (+) sense RNA (5)?

Back 25

1) enter cell, 2) translation to make RdRp, 3) replication to make (-) sense compliment, 4) compliment replication to make many (+) sense genome, 5) genomes translated to make proteins for assembly

Front 26

Injecting mRNA into a cell, will it cause disease?

Back 26

only if it is (+) sense, because it carries RdRp

Front 27

mRNA that codes for RdRp?

Back 27

(+) sense RNA

Front 28

RdRp?

Back 28

RNA Dependent RNA Polymerase, makes mRNA from RNA

Front 29

Steps in (-) sense RNA (5)?

Back 29

1) enter cell, 2) transcription of RNA to make mRNA, 3) each mRNA codes for different proteins including RdRp and assembly proteins, 4) replication to form (+) sense intermediate, 5)(+) sense used as template to make many mroe (-) sense genomes

Front 30

Transcription?

Back 30

synthesis of RNA

Front 31

Translation?

Back 31

protein synthesis

Front 32

Double stranded RNA synthesizes?

Back 32

(-) and (+) strands

Front 33

Double stranded RNA carries what?

Back 33

RdRp in particle

Front 34

Ambisense RNA viruses carry?

Back 34

RdRp in virus particle

Front 35

Ambisense genome?

Back 35

1/2 (+) sense, 1/2 (-) sense

Front 36

Retrovirus genome?

Back 36

diploid RNA (two + sense RNA)

Front 37

Retrovirus infection steps (5)?

Back 37

1)synthesis of (-) sense DNA from (+) sense RNA in cytoplasm, 2)digestion of (+)sense RNA by RNAse H in cytoplasm, 3)synthesis of (+)sense DNA from (-) sense DNA in cytoplasm, 4)entry of dsDNA to nucleus 5) transcription of viral mRNAs by host DNA dependent RNA polymerase II in nucleus

Front 38

DNA viruses replicate with?

Back 38

host DNA polymerase

Front 39

What receptor does HIV bind to?

Back 39

CD4

Front 40

What receptor does influenza bind to?

Back 40

Sialic acid

Front 41

What receptor does rhinovirus bind to?

Back 41

ICAM-1

Front 42

What receptor does rabies bind to?

Back 42

ACh receptor

Front 43

Cell fusion to form giant cells is called?

Back 43

Syncyticum formation

Front 44

Which viruses arise faster, DNA or RNA?

Back 44

RNA viruses arise faster

Front 45

How does a vaccine become virulent?

Back 45

spontaneous random RNA mistakes in genome

Front 46

How did the polio vaccine become virulent?

Back 46

usually injested, mutation allowed it to enter CNS to cause disease

Front 47

Flu pandemic happend due to what?

Back 47

genome reassortment (animal flu + human flu = new pathogenesis)

Front 48

Complementation?

Back 48

viral gene/protein rectifies defect in related virus

Front 49

Genome recombination?

Back 49

polymerase jumps from one genome to another

Front 50

In phenotypic masking/mixing, does the protein capsid matter?

Back 50

NO! the genome is always expressed, no matter the protein coating

Front 51

Growth curve-eclipse period?

Back 51

virus disappears from host for certain period of time

Front 52

Growth curve-latent period?

Back 52

virus is inside of the cell, but isn't released, therefore not causing disease

Front 53

Horizontal spread?

Back 53

person to person

Front 54

Vertical spread?

Back 54

mother to child during delivery

Front 55

Iatrogenic?

Back 55

medical practice

Front 56

Causes of Cruetzfeldt-Jacob disease?

Back 56

corneal transplantation, growth hormone from cadaver pituitary glands, neurosurgery

Front 57

Inapparent/subclinical infection?

Back 57

active virus replication but no symptoms

Front 58

Acute infections?

Back 58

active replication and severe symptoms, then goes away

Front 59

Persistent infections?

Back 59

active infection, variable disease (no symptoms or pain)...mosquitos, mice

Front 60

Latent infections?

Back 60

inactive virus hiding in body

Front 61

Humoral immunity antibodies?

Back 61

IgM, IgG, IgA

Front 62

Virus neutralization by antibody?

Back 62

antibody binds to virus so it can't attach or enter cells

Front 63

Passive immunity available for what viruses (4)?

Back 63

rabies, hepatitis B, chickenpox, measles

Front 64

Cell-mediated immunity?

Back 64

Tc cells recognize MHC-II protein

Front 65

Antibody can only neutralize viruses with?

Back 65

envelopes and glycoprotein spikes

Front 66

How does AZT work?

Back 66

uses decoy nucleotides to stop peptide chain

Front 67

HIV retrovirals?

Back 67

inhibit reverse transcriptase, cause peptide termination

Front 68

Protease inhibitors?

Back 68

inhibit processing of translated proteins

Front 69

Interferons?

Back 69

inhibit protein synthesis in virus-infected cells

Front 70

Acyclovir?

Back 70

inhibits viral DNA polymerase, purine nucleoside analog, terminates chains

Front 71

Gancyclovir?

Back 71

inhibits viral DNA polymerase in CMV

Front 72

ELISA?

Back 72

Enzyme Linked Immunosorbent Assay, detects antigen-antibody reactions using enzymes and color

Front 73

Immunofluorescense?

Back 73

fluorsecent virus-specific antibody put into virus-infected tissues

Front 74

In Situ Hybridization?

Back 74

viral acids or antigens in tissue specimens detected with virus-specific probes

Front 75

Hemagglutination?

Back 75

virus particles attract RBC

Front 76

Hemagglutination inhibition?

Back 76

antibodies bind to viruses to prevent the attraction of RBC

Front 77

Complement Fixation?

Back 77

virus-specific antibodies fix complement, won't lyse RBC

Front 78

Plaque assay?

Back 78

put virus on agar and let it lyse the cells. the #of holes on the agar is the # of viral particles

Front 79

Plaque assay used for what kind of virus?

Back 79

viruses causing cell death

Front 80

Helical viruses always have?

Back 80

RNA

Front 81

DNA virus mnemonic?

Back 81

HHAPPPy

Front 82

DNA viruses (6)?

Back 82

Herpes, Hepadna, Adeno, Papova, Parvo, Pox

Front 83

Naked RNA viruses (3)?

Back 83

picorna, calici, reoviridae (PCR)

Front 84

Icosahedral RNA viruses (5)?

Back 84

Reo, Picorna, Toga, Flavi, Calici

Front 85

RNA viruses that replicate in the nucleus (2)?

Back 85

retro, orthomyxo

Front 86

7 live attenuated viruses?

Back 86

oral polio (Sabin), adenovirus, measles, mumps, rubella, yellow fever, varicella-zoster

Front 87

5 killed viruses?

Back 87

killed polio (Salk), influenza, rabies, Japanese encephalitis B, hep A

Front 88

Name the Togaviruses (2)?

Back 88

rubella, alpha

Front 89

Rubella causes?

Back 89

German measles

Front 90

Symptoms of German measles?

Back 90

blotchy 3 day rash, upper respiratory infection,

Front 91

How many RNA molecules found in the Togavirus family particles?

Back 91

2 molecules

Front 92

What is a rash?

Back 92

immune response causing RBC to leak into extra-cellular matrix

Front 93

Congenital Rubella Syndrome cause?

Back 93

pregnant woman gets Rubella infection during 1st trimester

Front 94

Congenital Rubella Syndrome symptoms?

Back 94

cataracts (blindness), ductus arteriousis, thrombocytopenia purpura (rash), meningitis, mental retardation, neurosensory deafness

Front 95

Treatment for German Measles?

Back 95

none...self limiting in weeks

Front 96

Vaccine for German Measles?

Back 96

MMR (live attenuated virus)

Front 97

Diagnosis of German Measles?

Back 97

ELISA

Front 98

Transmission of German Measles?

Back 98

humans, no mosquito infection

Front 99

All insect-transmitted viruses cause?

Back 99

viremia

Front 100

How do insect-transmitted viruses reach the CNS?

Back 100

cross the blood-brain barrier

Front 101

Transmission of Alphaviruses?

Back 101

mosquito-transmitted

Front 102

Symptoms of Alphavirus infection?

Back 102

encephalitis in horses, birds; usually subclinical in humans

Front 103

WEE?

Back 103

Western Equine Encephalitis, found in Western US and Canada

Front 104

EEE?

Back 104

Eastern Equine Encephalitis, found in Eastern US

Front 105

VEE?

Back 105

Venezuelan Equine Encephalitis, found in Southern US, South and Central America

Front 106

Chikungunya?

Back 106

arthropathy (joint swelling and pain)

Front 107

Alphavirus vaccine given to?

Back 107

horses

Front 108

Arboviruses include what families?

Back 108

toga, flavi, rhabdo, reo, bunya

Front 109

All Arboviruses are?

Back 109

RNA viruses

Front 110

Clues for Arbovirus infection?

Back 110

marshlands, forests, stagnant water, abandoned tires, summer/early fall

Front 111

All Flaviviruses are?

Back 111

enveloped RNA (+) sense

Front 112

St. Louis Encephalitis?

Back 112

in USA, mosquito borne

Front 113

Japanese Encephalitis?

Back 113

Asian countries, pigs, birds, mosquito borne, killed virus vaccine available

Front 114

Tick Borne Encephalitis?

Back 114

Europe, tick borne

Front 115

Yellow Fever symptoms?

Back 115

hepatitis, jaundice, black vomit from stomach hemorrhaging

Front 116

Yellow Fever vaccine?

Back 116

17D live attenuated virus

Front 117

Dengue Fever symptoms?

Back 117

breakbone fever (flu-like, arthritis, rash), shock

Front 118

Hepatitis C is part of what family?

Back 118

flavi, NOT arbo

Front 119

Most common cause of transfusion associated, Non-A, Non-B hepatitis?

Back 119

Hepatitis C

Front 120

Hep C transmitted by?

Back 120

blood transfusion, IV drug use, sexual contact

Front 121

Hep C can cause?

Back 121

hepatocarcinoma (liver cancer)

Front 122

Treatment of Hep C?

Back 122

alpha interferon

Front 123

Coronavirus structure?

Back 123

enveloped, (+) sense RNA, with helical nucleocapsid

Front 124

Coronavirus causes?

Back 124

common cold, gastroenteritis

Front 125

Transmission of Coronavirus?

Back 125

aerosol, hand contact

Front 126

Structure of Picornaviridae?

Back 126

non-enveloped, (+) sense, viral protein on 5' end of genome

Front 127

Picornaviridae includes what species?

Back 127

polio, coxsackie, rhinovirus, Hep A

Front 128

Abortive poliomyelitis?

Back 128

no CNS involvement

Front 129

Aseptic meningitis?

Back 129

stiff neck, meningeal irritation

Front 130

Paralytic poliomyelitis?

Back 130

assymetric flaccid paralysis

Front 131

Bulbar polio?

Back 131

paralysis of pharynx and soft palate, dysphagia, hydrophobia, damaged CN9 and CN10

Front 132

Salk vaccine?

Back 132

killed, subcutaneous, includes 1, 2, 3 serotypes

Front 133

Sabin vaccine?

Back 133

oral

Front 134

Coxsackie A?

Back 134

foot-and-mouth disease, vesicular lesions on hands and face, hemorrhagic conjuncitivitis, pharyngitis, vesicles on soft palate

Front 135

Coxsackie B?

Back 135

pleurodynia, aseptic meningitis, myocardiopathy, myalgia

Front 136

Coxsackie A vesicles on soft palate look like?

Back 136

HSV-1

Front 137

Rhinovirus?

Back 137

#1 cause of common cold

Front 138

Rhinovirus transmitted mainly by?

Back 138

school children

Front 139

Hepatitis A structure?

Back 139

naked (+) sense RNA

Front 140

Hepatitis A transmission?

Back 140

raw seafood, fecal-oral transmission, contaminated water,

Front 141

Prevention of Hep A?

Back 141

inactivated vaccine for foreign travelers

Front 142

Calici viruses include?

Back 142

Norwalk (Noro), Hep E

Front 143

Noro virus structure?

Back 143

naked (+) sense RNA

Front 144

Symptoms of Norovirus infection?

Back 144

gastroenteritis, hepatitis

Front 145

Norovirus transmission?

Back 145

fecal-oral, contaminated water, raw shellfish

Front 146

Hep E structure?

Back 146

naked (+) sense RNA

Front 147

Hep E transmission?

Back 147

fecal-oral, raw seafood

Front 148

Hep E symptoms?

Back 148

gastroenteritis and hepatitis

Front 149

Astrovirus structure?

Back 149

naked (+) RNA virus

Front 150

Astrovirus symptoms?

Back 150

infantile diarrhea

Front 151

Astrovirus transmission?

Back 151

fecal-oral

Front 152

RNA (-) sense enveloped, bullet-shaped virus?

Back 152

Rhabdovirus

Front 153

Rhabdo causes?

Back 153

Rabies!

Front 154

Rhabdo multiplies where?

Back 154

muscle cells

Front 155

Rabies found only in?

Back 155

nervous system...NO viremia

Front 156

Highest concentration of Rhabdovirus in infected person?

Back 156

hippocampus

Front 157

How does rabies virus reach the CNS?

Back 157

enters nerves at the neuromuscular junction

Front 158

How does rabies virus reach the saliva?

Back 158

through autonomic nerves to the salivary gland

Front 159

Transmission of Rhabdovirus?

Back 159

bite of rabid animal: dogs, cats, bats, foxes, wolves, raccoons, skunks

Front 160

Rabies NOT transmitted by?

Back 160

mosquitos

Front 161

Symptoms of rabies arise in ____ mos?

Back 161

1 to 3 mos after bite

Front 162

Viruses found in saliva (3):

Back 162

EBV, mumps, rabies

Front 163

Symptoms of rabies?

Back 163

hyperexcitability, convulsions, hydrophobia (swallowing pain), paralysis, coma, death

Front 164

Rabies symptoms accelerated by?

Back 164

animal bite on face

Front 165

Negri bodies?

Back 165

cytoplasmic inclusion bodies in hippocampus and spinal cord

Front 166

Detection of rhabdovirus?

Back 166

fluorescent examination of animal brain

Front 167

Rabies vaccine?

Back 167

killed vaccine for high risk people (animal handlers)

Front 168

Paramyxo structure?

Back 168

enveloped, 1 segment of (-) sense RNA

Front 169

Paramyxo contains what protein?

Back 169

HN: Hemagglutinin-Nuraminidase, F protein

Front 170

All paramyxos cause?

Back 170

syncytia formation

Front 171

Members of paramyxo family?

Back 171

parainfluenza, RSV, mumps, measles

Front 172

Parainfluenza 1 symptoms?

Back 172

acute croup (laryngotracheobronchitis) in infants, upper respiratory

Front 173

Parainfluenza 2 symptoms?

Back 173

upper respiratory infection, sometimes lower respiratory infection

Front 174

Parainfluenza 3 symptoms?

Back 174

2nd major viral cause of bronchitis and pneumonia in children

Front 175

#1 cause of lower respiratory infection, pneumonia, bronchitis in infants?

Back 175

RSV (Respiratory Syncytial Virus)?

Front 176

RSV proteins?

Back 176

F protein, G protein

Front 177

F protein?

Back 177

mediates membrane fusion