XIII - Virology Flashcards
(366 cards)
1
Q
Size of Viruses
A
20-300 nm
2
Q
All viruses have a _____ coat.
A
protein coat (capsid), lipoprotein envelope in some
3
Q
Virus capsids are composed of
A
repeating capsomeres
4
Q
All helical viruses are
A
enveloped
5
Q
Icosahedral (spherical) viruses can be enveloped or
A
naked
6
Q
Viral Proteins
A
surface proteins, DNA or RNA polymerases, matrix protein, antigenic (serotypic) variants
7
Q
Viral Proteins: Attachment to host cell receptors
A
surface protein
8
Q
Viral Proteins: Interaction between nucleocapsid and envelope
A
matrix protein
9
Q
Viral Proteins: Evasion of host defenses
A
antigenic (serotypic) variants
10
Q
Lipid membrane derived from the host cell, acquired as the virus exits from the cell in a process called budding
A
viral envelope
11
Q
All enveloped viruses acquire their envelope from plasma membrane except
A
herpesvirus - nuclear membrane
12
Q
Enveloped viruses are _____ stable and _____ inactivated.
A
less stable, easily inactivated
13
Q
Naked Viruses
A
RNA - Calici, Picorna, Reo, DNA - Parvo, Adeno, Papilloma, Polyoma
14
Q
Purified nucleic acids of most dsDNA (except poxviruses and HBV) and (+) strand genome ssRNA viruses are
A
infectious
15
Q
Naked nucleic acids of (-) strand ssRNA and dsDNA viruses are
A
not infectious
16
Q
Naked nucleic acids of (-) strand ssRNA and dsDNA viruses require
A
enzymes contained in the complete virion
17
Q
Infectious particles composed entirely of protein which case transmissible spongiform encephalopathies, highly resistant to inactivation, do not elicit an inflammatory response or an antibody response
A
Prions
18
Q
Prion Proteins: Non-pathogenic
A
alpha-helix
19
Q
Prions Proteins: Pathogenic
A
beta-pleated sheet
20
Q
All viruses are haploid except
A
retroviruses
21
Q
Genomes of RNA viruses can either have positive or negative
A
polarity
22
Q
Some RNA viruses have a _____ genome.
A
segmented genome
23
Q
Viruses with Segmented Genomes
A
Bunyavirus, Orthomyxovirus (influenza), Arenavirus, Reovirus
24
Q
Must transcribe negative strand to positive, virion brings its own RNA-dependent polymerase
A
Negative-Strand RNA Viruses
25
Negative-Strand RNA Viruses
Arenavirus, Bunyavirus, Paramyxovirus, Orthomyxovirus, Filovirus, Rhabdovirus
26
Viral Genetics: Mutations can produce
antigenic, drug-resistant or attenuated variants
27
Viral Genetics: Causes epidemics
genomic reassortment
28
Viral Genetics: One virus produces a protein that can be used by another virus
complementation
29
Viral Genetics: Two different viruses infect the same cell
phenotypic mixing
30
Virus Life Cycle
attachment → penetration → uncoating → biosynthesis → maturation → release
31
Viral Growth Curve: A single virus particle infects a cell
Phase 0 - Entry
32
Viral Growth Curve: Virus decreases in number but continues to function
Phase 1 - Decline
33
Viral Growth Curve: No virus is detectable inside the cell
Phase 2 - Eclipse Period
34
Viral Growth Curve: Dramatic increase in amount of detectable viruses
Phase 3 - Rise Period
35
Viral Growth Curve: Amount of detectable viruses reach a plateau
Phase 4 - Latent Period
36
Viral Growth Curve: Marked derangement of cell function leading to lysis and cell death, remarkable amplification in number of viral particles
Phase 5 - Cytopathic Effect
37
Outcomes of Viral Infection: Visual or functional change in infected cells
Cytopathic Effect
38
Outcomes of Viral Infection: Oncogenic viruses induce transformation and unrestrained growth
Malignant Transformation
39
Outcomes of Viral Infection: Infected cells appear normal but are producing large numbers of progeny viruses
Commensal Symbiosis
40
Virulence Factors: Bind cytokines and block their ability to interact with receptors on their intended targets
Cytokine Decoys
41
Virulence Factors: Reduce the expression of antigen presenting cells and inactivate complement
Virokines
42
Viruses: Virulence Factors
antigenic variants of surface proteins, cytokine decoys, virokines
43
Persistent Viral Infections: Produce viruses for long periods of time, can serve as a source of infection for others
Carrier State
44
Persistent Viral Infections: Not producing virus at present but can be reactivated at a subsequent time
Latent Infections
45
Persistent Viral Infections: Long incubation period (years)
Slow Virus Infections
46
Viruses: Presumptive Identification
cytopathic effect, hemadsorption, interference, decrease in acid production (phenol red)
47
Presumptive Identification of Viruses: Attachment of RBCs to the surface of infected cells
hemadsorption
48
Presumptive Identification of Viruses: Disturbance with CPE by another virus
interference
49
Presumptive Identification of Viruses: Decrease in acid production by infected, dying cells
phenol red
50
Viruses: Definitive Diagnosis
complement fixation, hemagglutination inhibition, neutralization, fluorescent-antibody assay, radioimmunoassay, Enzyme-Linked Immunosorbent Assay (ELISA)
51
Virus Serologic Tests: Finding an antibody in one who previously had none
seroconversion
52
Virus Serologic Tests: Ig in current infection
IgM
53
Virus Serologic Tests: Ig that can be from previous infection
IgG
54
Gold Standard in Viral Dagnosis
viral DNA/RNA
55
Vaccines: Induce humoral and cell-mediated immunity but may revert to virulence on rare occasions, dangerous to give to immunocompromised patients or their close contacts
Live-Attenuated Vaccines
56
Only live-attenuated vaccine that may be given to HIV (+) patients
MMR
57
Live-Attenuated Vaccines
yellow fever, chicken pox (VZV), polio (Sabin's), MMR
58
Vaccines: Induce only humoral immunity but are stable
Killed Vaccines
59
Killed Vaccines
rabies, influenza, polio (Salk's), hepatitis A
60
Recombinant Vaccines
Hepatitis B (HBsAg), HPV (6, 11, 16, 18)
61
Hepatitis Virus: A
Picornaviridae
62
Hepatitis Virus: B
Hepadnaviridae
63
Hepatitis Virus: C
Flaviviridae
64
Hepatitis Virus: D
not classified
65
Hepatitis Virus: E
Caliciviridae
66
DNA Viruses
Hepadna, Herpes, Adeno, Pox, Parvo, Polyoma, Papilloma
67
All DNA viruses have dsDNA except
Parvovirus - ssDNA
68
All DNA viruses have linear DNA except
Papilloma, Polyoma, Hepadna
69
All DNA viruses are icosahedral except
Poxvirus - complex symmetry
70
All DNA viruses replicate in the nucleus except
Poxvirus - cytoplasm, Guarnieri bodies
71
Naked DNA Viruses
Parvovirus, Adenovirus, Human Papillomavirus
72
Naked DNA Viruses: Respiratory, transplacental, non-oncogenic, no vaccine
Parvovirus
73
Naked DNA Viruses: Respiratory, fecal-oral, non-oncogenic, vaccine available
Adenovirus
74
Naked DNA Viruses: Sexual, skin contact, oncogenic, vaccine available
Human Papillomavirus
75
Naked virus with icosahedral symmetry, ssDNA genome, one serotype
Parvovirus B19
76
Parvovirus: Transmission
respiratory droplets, transplacental
77
Parvovirus: Infections
Erythema Infectiosum (5th Disease), Aplastic Crisis, Fetal Infections, Arthritis, Chronic B19 Infection
78
Bright red cheeks (slapped cheeks), fever, coryza, sore throat
Erythema Infectiosum (5th Disease) - Parvovirus B19
79
Transient but severe aplastic anemia in children, sickle cell anemia, thalassemia, spherocytosis
Aplastic Crisis - Parvovirus B19
80
Parvovirus Fetal Infections: 1st Trimester
fetal death
81
Parvovirus Fetal Infections: 2nd Trimester
hydrops fetalis
82
Viral immune-complex arthritis of small joints
Parvovirus Arthritis
83
Chronic Parvovirus B19 infection causes _____ in immunodeficient patients.
pancytopenia
84
Naked virus, dsDNA, icosahedral nucleocapsid, only virus with fiber (penton), 41 antigenic types, Cowdry type B intranuclear inclusions
Adenovirus
85
Adenovirus: Transmission
aerosol droplet, fecal-oral, direct contact
86
Adenovirus: URT
pharyngitis, conjunctivitis, coryza
87
Adenovirus: LRT
bronchitis, atypical pneumonia
88
Adenovirus: GIT
acute gastroenteritis
89
Adenovirus: GUT
hemorrhagic cystitis
90
Adenovirus: Histopathology
Cowdry type B intranuclear inclusions
91
Naked virus with circular dsDNA, icosahedral nucleocapsid, at least 100 types
HPV
92
HPV: Transmission
sexually, direct contact
93
Infect squamous cells and induce formation of cytoplasmic vacuole (koilocytes), genes E6 & E7
HPV
94
HPV: Encode proteins that inactivate tumor suppressor genes
genes E6 & E7
95
HPV: Skin and plantar warts
HPV 1-4
96
HPV: Genital warts (condyloma acuminata), respiratory tract
HPV 6 & 11
97
Most common viral STD
HPV
98
HPV: Carcinoma of cervix, penis, anus
HPV 16, 18, 31, 33
99
HPV: Treatment for Genital Warts
Podophyllin
100
HPV: Treatment for Skin Warts
Liquid Nitrogen
101
HPV: Treatment for Plantar Warts
Salicylic Acid
102
HPV: Prevention
vaccine for HPV 6, 11, 16, 18, 9-26 y.o.
103
Only causes disease in immunocompromised hosts, causes progressive multifocal leukoencephalopathy (PML) in AIDS patients
JC Polyoma Virus
104
Demyelinating disease that affects oligodendrocytes characterized by deficits in speech, coordination and memory, AIDS patients
Progressive Multifocal Leukoencephalopathy (PML)
105
Only causes disease in immunocompromised hosts, causes hemorrhagic cystitis and nephropathy in patients with solid organ (kidney) and bone marrow transplants
BK Polyoma Virus
106
Enveloped DNA Virsues
HSV, VZV, EBV, CMV, HHV
107
Herpesviruses
CMV, HSV, EBV, VZV
108
Enveloped virus, icosahedral nucleocapsid, linear dsDNA, vesicle filled with virus particles and cell debris, multinucleated giant cells on Tzanck smear, large, pink-purple intranuclear inclusions (Cowdry type A)
Herpes Simplex Virus
109
Herpes Simplex Virus: Transmission
HSV 1 - saliva, direct (above umbilicus), HSV 2 - sexual, transvaginal (below umbilicus)
110
Herpes Simplex Virus: Site of Latency
HSV 1 - trigeminal ganglia, HSV 2 - lumbosacral ganglia
111
HSV: Gingivostomatitis, herpes labialis (lips), keratoconjunctivitis, temporal lobe encephalitis, herpetic whitlow (fingers), herpes gladiatorum (trunk)
HSV 1
112
HSV: Genital herpes (painful anogenital vesicles), neonatal herpes (contact within birth canal), aseptic meningitis
HSV 2
113
Herpes Simplex Virus: Treatment
Acyclovir
114
Needs virus kinase to be activated, analogue of guanine, shortens duration of lesions, reduces the extent of shedding of the virus, no effect on the latent sate
Acyclovir
115
Enveloped virus, icosahedral nucleocapsid, linear dsDNA, infects URT, hematogenous spread to the skin, becomes latent in the dorsal root ganglia, may reactivate as zoster, multinucleated giant cells with intranuclear inclusions
Varicella-Zoster Virus
116
Varicella-Zoster Virus: Transmission
respiratory droplets, direct contact with lesions
117
Varicella-Zoster Virus: Diseases
Varicella, Zoster, Ramsay Hunt Syndrome
118
VZV: Incubation period of 14-21 days, vesicular centrifugal rash in different stages (dewdrop on a rose petal), pneumonia, encephalitis, Reye's Syndrome
Varicella
119
Aspirin in Pediatric Cases
Kawasaki, ARF, JRA
120
VZV: Painful vesicles along dermatomal distribution, debilitating pain (postherpetic neuralgia)
Zoster
121
VZV: Involvement of geniculate ganglion causes facial nerve paralysis
Ramsay Hunt Syndrome
122
Varicella-Zoster Virus: Site of Latency
dorsal root ganglia
123
Varicella-Zoster Virus: Treatment
Acyclovir - moderate to severe (shortens duration of lesions)
124
Enveloped virus, icosahedral nucleocapsid, linear dsDNA, cultured in shell tubes, (-) neutrophil test
Cytomegalovirus
125
Cytomegalovirus: Transmission
body fluids, transplacental, organ transplant
126
Immediate early proteins, giant cells with owl's-eye nuclear inclusions
Cytomegalovirus
127
Cytomegalovirus: Translated from premade mRNAs, impair assembly of the MHC class I-viral peptide complexes
Immediate Early Proteins
128
Cytomegalovirus: Diseases
congenital CMV, heterophil (-) mononucleosis, systemic CMV
129
Most common cause of congenital abnormalities
Cytomegalovirus
130
Microcephaly, seizures, deafness, jaundice, purpura (blueberry muffin), most common when mother is infected in the 1st trimester
Congenital CMV
131
Fever, lethargy, abnormal lymphocytes in peripheral blood smears
Heterophil (-) Mononucleosis
132
Pneumonitis, hepatitis, colitis, retinitis in HIV
Systemic CMV
133
Cytomegalovirus: Treatment
Gancyclovir (resistant to Acyclovir), Foscarnet - retinitis
134
Enveloped virus, icosahedral nucleocapsid, linear dsDNA, infects mainly lymphoid cells (B-cells → Downey cells), elicits specific antibodies and nonspecific heterophil antibodies
Epstein-Barr Virus
135
Epstein-Barr Virus: Transmission
saliva
136
Kissing Disease
Epstein-Barr Virus
137
Epstein-Barr Virus: Diseases
Infectious Mononucleosis, malignancies
138
Fever, sore throat, lymphadenopathy, splenomegaly, splenic rupture
Infectious Mononucleosis
139
Epstein-Barr Virus: Malignancies
Burkitt's Lymphoma (Africans), B-cell Lymphomas, Nasopharyngeal CA (Chinese), Hairy Leukoplakia (AIDS)
140
Malignancy of vascular endothelial cells, flat to nodular dark purple skin lesions at multiple sites
Kaposi's Sarcoma (Human Herpesvirus 8)
141
Kaposi's Sarcoma: Treatment
surgical excision, radiation
142
Only disease that has been eradicated from Earth
Smallpox (Variola Virus)
143
Largest virus, brick-shaped poxvirus, Guarnieri bodies (intracytoplasmic eosinophilic inclusions)
Smallpox (Variola Virus)
144
Smallpox: Transmission
aerosol, contact
145
Smallpox: Incubation Period
7-14 days
146
Smallpox: Findings
prodrome of fever and malaise followed by centrifugal rash
147
Pinkish, papular skin lesions with an umbilicated center, Henderson-Peterson bodies (intracytoplasmic eosinophilic inclusions)
Molluscum Contagiosum
148
Molluscum Contagiosum: Transmission
direct contact
149
Molluscum Contagiosum: Treatment
Cifodivir
150
Enveloped virus, incomplete circular dsDNA
Hepadnaviridae (Hepatitis B)
151
Hepatitis Types: Asymptomatic
Hepatitis A
152
Hepatitis Types: Blood-borne
Hepatitis B
153
Hepatitis Types: Chronic, cirrhosis, carcinoma, carriers
Hepatitis C
154
Hepatitis Types: Enteric, expectant mothers, epidemics
Hepatitis E
155
Hepatitis Types: Enteric infections
Hepatitis A & E
156
Hepadnaviridae: Transmission
blood, birth, sexual
157
Hepadnaviridae: Virulence Factors
HBsAg - surface antigen, HBcAg - core antigen, HBeAg - e antigen
158
Only DNA virus that produces DNA by reverse transcription with mRNA as template
Hepadnaviridae (Hepatitis B)
159
Hepadnaviridae causes hepatocellular injury due to
immune attack (HBV has no cytopathic effect)
160
Hepadnaviridae: Incubation Period
10-12 weeks
161
Fever, anorexia, jaundice, dark urine, pale feces, elevated transaminase levels, cirrhosis, hepatocellular CA, autoimmune vasculitides (polyarteritis nodosa)
Hepadnaviridae (Hepatitis B)
162
Hepatitis B Complications: Functional renal failure from hepatic injury in the abscence of renal pathology
Hepatorenal Syndrome
163
Hepatitis B Complications: Vascular dilatations cause overperfusion relative to ventilation leading to V/Q mismatch and hypoxemia
Hepatopulmonary Syndrome
164
Hepatitis B Complications
hepatorenal syndrome, hepatopulmonary syndrome, portal HPN, hepatic encephalopathy
165
Hepadnaviridae: Treatment
Interferon α, Lamivudine
166
Hepadnaviridae: Prevention
vaccination - first vaccine to prevent human cancer
167
All RNA viruses have ssRNA except
Reovirus, Rotavirus (dsRNA)
168
All RNA viruses replicate in the cytoplasm except
Influenza, Retrovirus (nucleus)
169
Picornaviridae
Polio, Echo, Rhino, Coxsackie, Hepatitis A
170
Naked nucleocapsid, ssRNA with (+) polarity, oral-fecal transmission, replicates in motor neurons in the anterior horn of the spinal cord causing paralysis
Poliovirus
171
Host range is limited to primates due to the binding of the viral capsid protein to a receptor found only on primate cell membranes
Poliovirus
172
Has 3 serologic (antigenic) types based on different antigenic determinants on the outer capsid proteins
Poliovirus
173
Poliovirus: Diseases
asymptomatic, abortive poliomyelitis, non-paralytic poliomyelitis, paralytic poliomyelitis
174
Poliovirus: Most common clinical form, mild, febrile illness, headache, sore throat, nausea, vomiting
abortive poliomyelitis
175
Poliovirus: Aseptic meningitis
non-paralytic poliomyelitis
176
Poliovirus: Flaccid paralysis, permanent motor nerve damage
paralytic poliomyelitis
177
Poliovirus: Histopathology
Cowdry type B intranuclear inclusions
178
Poliovirus: Prevention
killed vaccine (Salk, IPV), live-attenuated vaccine (Sabin, OPV)
179
Polio Vaccine: Interrupts transmission
live-attenuated vaccine (Sabin, OPV)
180
Polio Vaccine: Induces humoral IgG
killed vaccine (Salk, IPV), live-attenuated vaccine (Sabin, OPV)
181
Polio Vaccine: Induces intestinal IgA
live-attenuated vaccine (Sabin, OPV)
182
Polio Vaccine: Affords secondary protection by spread to others
live-attenuated vaccine (Sabin, OPV)
183
Polio Vaccine: Interferes with replication of virulent virus in gut
live-attenuated vaccine (Sabin, OPV)
184
Polio Vaccine: Reverts to virulence
live-attenuated vaccine (Sabin, OPV)
185
Polio Vaccine: Co-infection with enteroviruses may impair immunization
live-attenuated vaccine (Sabin, OPV)
186
Polio Vaccine: Can cause disease in the immunocompromised
live-attenuated vaccine (Sabin, OPV)
187
Polio Vaccine: Injection
killed vaccine (Salk, IPV)
188
Polio Vaccine: Oral
live-attenuated vaccine (Sabin, OPV)
189
Polio Vaccine: Requires refrigeration
live-attenuated vaccine (Sabin, OPV)
190
Polio Vaccine: Short immunity
killed vaccine (Salk, IPV)
191
Polio Vaccine: Long-lasting immunity
live-attenuated vaccine (Sabin, OPV)
192
Naked nucleocapsid, ssRNA, (+) polarity, classified based on pathogenicity in mice
Coxsackievirus
193
Coxsackievirus: Transmission
oral-fecal
194
Coxsackievirus A: Diseases
herpangina, hand-foot-and-mouth disease, hemorrhagic conjunctivitis, aseptic meningitis
195
Coxsackievirus B: Diseases
pleurodynia, myocarditis, pericarditis, aseptic meningitis
196
Coxsackievirus: Fever, sore throat, tender vesicles in oropharynx
herpangina
197
Coxsackievirus: Vesicular rash on hands and feet and ulcerations in the mouth
hand-foot-and-mouth disease
198
Coxsackievirus: Fever, severe pleuritic chest pain
pleurodynia
199
Coxsackievirus: Fever, chest pain, congestive failure
myocarditis, pericarditis
200
Most common cause of myocarditis and pericarditis
Coxsackievirus
201
Most common cause of aseptic meningitis
Coxsackievirus
202
Coxsackievirus, Poliovirus and Echovirus are
enteroviruses
203
Enteric Cytopathic Human Orphan
ECHOvirus
204
Virus initially not associated with any disease
Echovirus
205
Aseptic meningitis, URTI, febrile illness ± rash, infantile diarrhea, hemorrhagic conjunctivitis
Echovirus
206
Echovirus: Transmission
fecal-oral
207
Only respiratory picornavirus, causes common colds
Rhinovirus
208
Naked nucleocapsid virus, ssRNA, (+) polarity, more than 100 serotypes, affect mainly the nose and conjunctiva, replicates better at 33°C, acid-labile, host range limited to humans and chimpanzees
Rhinovirus
209
Rhinovirus: Transmission
aerosol droplets, hand-to-nose contact
210
Naked nucleocapsid virus, ssRNA, (+) polarity, frequently infects children, self-limited hepatitis, anti-HAV IgM (most important test), Enterovirus 72, has 1 serotype
Hepatitis A Virus (Picornaviridae)
211
Hepatitis A Virus: Transmission
fecal-oral
212
Hepatitis A Virus: Diagnosis
anti-HAV IgM
213
Fecal-oral transmission, no chronic carrier state, no cirrhosis, no hepatocellular CA, high mortality in pregnant women, causes hepatitis epidemics
Hepatitis E Virus (Caliciviridae)
214
Non-enveloped virus, icosahedral nucleocapsid, one piece of ssRNA, (+) polarity, sudden onset of vomiting and diarrhea accompanied by fever and abdominal cramping
Norwalk Virus/Norovirus (Viral Gastroenteritis)
215
Most common cause of non-bacterial diarrhea in adults
Norwalk Virus/Norovirus
216
Naked double-layered capsid with 10-11 segments of dsRNA, most common cause of childhood diarrhea
Rotavirus (Viral Gastroenteritis)
217
Enveloped virus, helical nucleocapsid, segmented ssRNA, (-) polarity, most common cause of respiratory tract infections
Influenza Virus
218
Influenza Virus: Major Antigens
hemagglutinin (H), neuraminidase (N)
219
Influenza Virus: Transmission
respiratory droplet
220
Influenza Virus: Worldwide epidemics (pandemics)
Influenza A
221
Influenza Virus: Major outbreaks
Influenza B
222
Influenza Virus: Mild respiratory tract infections, does not cause outbreaks
Influenza C
223
Influenza Virus: Pathogenesis
Envelope → 2 different types of spikes: hemagglutinin (H), neuraminidase (N)
224
Influenza Virus: 16 types of hemagglutinin (H), 9 types of neuraminidase (N)
Influenza A
225
Binds to the cell surface receptor (neuraminic acid/sialic acid) to initiate infection of the cell, target of neutralizing antibody
hemagglutinin
226
Cleaves neuraminic acid (sialic acid) to release progeny virus from infected cell, degrades the protective layer of mucus in the respiratory tract → enhances access to the respiratory epithelial cells
neuraminidase
227
Animal influenza viruses are the source of RNA segments that encode the antigenic _____ variants that cause epidemics among humas.
antigentic shift
228
Creation of new influenza variants
Reassortment
229
Common source of new influenza variants
aquatic birds (waterfowl)
230
Influenza "Mixing Bowl"
Pigs
231
Influenza Variants: Waterfowl
H1-H16, N1-N9
232
Influenza Variants: Humans
H1-H3, N1 and N2
233
Influenza: Only a human virus (no animal source), undergoes antigenic drift, new version every year
Influenza B
234
Influenza Variants: Major changes based on the reassortment of segments of the genome RNA, causes pandemics
antigenic SHIFT
235
Influenza Variants: Minor changes based on mutations in the genome RNA
antigenic DRIFT
236
Influenza: Incubation Period
24-48 hours
237
Fever, myalgias, headache, sore throat, cough
Influenza
238
Influenza: Complications
Staphylococcal Pneumonia, Reye's Syndrome
239
Influenza: Treatment
Oseltamivir, Zanamivir, Influenza A - Amantadine, Rimantadine (Parkinson's medicine, prevents viral uncoating)
240
Influenza: Prevention
annual vaccination
241
Paramyxoviridae
Parainfluenza, RSV, Measles, Mumps
242
Paramyxoviridae: Hemagglutinin (+), Neuraminidase (-), Fusion Protein (+)
Measles
243
Paramyxoviridae: Hemagglutinin (+), Neuraminidase (+), Fusion Protein (+)
Mumps, Parainfluenza
244
Paramyxoviridae: Hemagglutinin (-), Neuraminidase (-), Fusion Protein (+)
RSV
245
Enveloped virus, helical nucleocapsid, one piece of ssRNA, (-) polarity, infects URT, spreads to reticuloendothelial cells, hematologic spread to skin, transiently depress cell-mediated immunity
Measles
246
Multinucleated giant cells (Warthin-Finkeldey bodies) form as a result of the fusion protein in the spikes - characteristic of the lesions, lifelong immunity after recovery
Measles
247
Measles rash is caused by
cytotoxic T cells, attacking the infected vascular endothelial cells in the skin
248
Measles: Shortly after the rash appears, the virus can no longer be recovered and the patient _____ spread the virus.
can no longer spread the virus
249
Measles: Incubation Period
10-14 days
250
Measles: Pathognomonic Sign
Koplik's Spots
251
Measles: Bright red lesions with white central dot on buccal mucosa
Koplik's Spots
252
Measles: Rash
face → trunk → extremities → palms/soles
253
Rash: face → trunk → extremities → palms/soles
Measles
254
Measles: Complications
encephalitis, pneumonia, subacute sclerosing panencephalitis (SSPE) or Dawson disease
255
Measles: Triad
cough, coryza, conjunctivitis
256
Measles: Prevention
live-attenuated vaccine, Vitamin A - reduces severity
257
Enveloped virus, helical nucleocapsid, one piece of ssRNA, (-) polarity, initially infects URT, spreads to local lymph nodes, hematogenous spread to parotid glands, testes, ovaries, meninges, pancreas
Mumps
258
Mumps: Transmission
respiratory droplets
259
Mumps: Incubation Period
18-21 days
260
Tender swelling of the parotid glands (parotitis) with increased pain when drinking citrus juices, orchitis, meningitis, resolves in 1 week
Mumps
261
Mumps: Prevention
live-attenuated vaccine
262
Surface spikes are fusion proteins (not hemagglutinin or neuraminidase) which causes cells to fuse, forming multinucleated giant cells (syncitia), humans are the natural hosts
Respiratory Syncitial Virus
263
Most important cause of pneumonia and bronchiolitis in infants
Respiratory Syncitial Virus
264
Severe disease in infants due to immunologic cross-reaction with maternal antibodies
Respiratory Syncitial Virus
265
Respiratory Syncitial Virus: Treatment
Ribavirin
266
Inspiratory stridor, cough, hoarseness, steeple sign (subglottic stenosis)
Laryngotracheobronchitis / Croup (Parainfluenza Virus 1 & 2)
267
Laryngotracheobronchitis: Treatment
Racemic Epinephrine
268
Bullet-shaped enveloped virus with helical nucleocapsid, one piece of ssRNA, (-) polarity
Rabies
269
Rabies: Transmission
animal bite - dog, cats, skunks, racoons, bats
270
Multiplies locally at the bite site, infects sensory neurons and moves by axonal transport to CNS
Rabies
271
Rabies: Histopathology
Negri bodies
272
Rabies: Incubation Period
2-16 weeks - depends on bite site
273
Confusion, lethargy, hypersalivation, laryngospasm, hydrophobia, invariably fatal when encephalitis develops
Rabies
274
Rabies: Treatment and Prevetion
pre- and post-exposure vaccine (only vaccine routinely used post-exposure), post-exposure Ig
275
Rabies Post-Exposure Prophylaxis: Touching or feeding animals, licks on skin
Category I - no treatment
276
Rabies Post-Exposure Prophylaxis: Nibbling of uncovered skin, minor scratches or abrasions without bleeding, licks on broken skin
Category II - vaccine
277
Rabies Post-Exposure Prophylaxis: Single or multiple transdermal bites or scratches, contamination of mucous membranes with saliva from licks, exposure to bat bites or scratches
Category III - vaccine + Ig
278
Enveloped virus, helical nucleocapsid, one piece of ssRNA, (+) polarity, prominent club-shaped spikes forming a corona, 2 serotypes
Coronavirus
279
Coronavirus: Reservoir
horseshoe bat
280
Coronavirus: Intermediate Host
civet cat
281
Coronavirus: Transmission
respiratory droplets
282
Coronavirus: Diseases
common cold, Severe Acute Respiratory Syndrome (SARS)
283
SARS: Incubation Period
2-10 days
284
Atypical pneumonia rapidly progressing to ARDS, virus binds to ACE-2 receptors, non-cavitary "ground glass" infiltrates
Severe Acute Respiratory Syndrome (SARS)
285
Enveloped virus, icosahedral nucleocapsid, one piece of ssRNA, (+) polarity, flavivirus, 4 serotypes
Dengue
286
Dengue: Vector
Aedes aegypti mosquito
287
Dengue: Diagnosis
dengue IgM, tourniquet test
288
Influenza-like syndrome with maculopapular rash and severe pains in muscles and joints (breakbone fever), leukopenia, thrombocytosis, hemorrhagic shock due to cross-reacting antibody during 2nd infection
Dengue
289
Probable Dengue
endemic area, fever ± (nausea, vomiting, rash, aches/pains, tourniquet test (+), leukopenia, any warning sign)
290
Dengue: Warning Signs
abdominal pain or tenderness, persistent vomiting, clinical fluid accumulation, mucosal bleed, lethargy, restlessness, liver enlargement > 2cm, increase in Hct concurrent with rapid decrease in PC
291
Severe Dengue
severe plasma leakage (shock, fluid accumulation with respiratory distress), severe bleeding, severe organ involvement (AST or ALT ≥ 1000, impaired consciousness)
292
Dengue: Prevention
insecticides, draining stagnant water, mosquito repellant
293
Enveloped virus, one piece of ssRNA, (+) polarity, 6 serotypes, hypervariable region in envelope glycoprotein
Hepatitis C
294
Hepatitis C: Diagnosis
anti-HCV or HCV RNA
295
Most prevalent blood-borne pathogen
Hepatitis C
296
IV drug abusers, needle-stick injury, vertical transmission, sexual transmission
Hepatitis C
297
Most common needle-stick injury pathogen
Hepatitis B
298
Replication in liver enhanced by liver-specific micro-RNA, hepatocellular injury due to immune attack, alcoholism greatly enhances rate of hepatocellular CA, chronic carriage is higher than HBV
Hepatitis C
299
Hepatitis C: Incubation Period
8 weeks
300
Hepatitis C: Autoimmune Reactions
thyroiditis, autoantibodies, MPGN, porphyria cutanea tarda, DM
301
Main cause of essential mixed cryoglobulinemia
Hepatitis C
302
Hepatitis C: Treatment for Acute Disease
Interferon
303
Hepatitis C: Treatment for Chronic Disease
Peginterferon, Ribavarin
304
Hepatitis C: Treatment for Severe Disease
liver transplant
305
Most common indication for liver transplant
Hepatitis C
306
Enveloped virus, icosahedral nucleocapsid, one piece of ssRNA, (+) polarity, togavirus
Rubella
307
Rubella: Transmission
respiratory droplets, transplacental
308
Rubella: Diseases
German Measles, Congenital Rubella Syndrome
309
German Measles: Incubation period
14-21 days
310
Prodrome followed by 3-day maculopapular rash and posterior CLAD, rash (face → trunk → arms/legs), immune-complex polyarthritis in adults
German Measles (Rubella)
311
Infected during 1st trimester, PDA, congenital cataracts, sensorineural deafness, mental retardation
Congenital Rubella Syndrome
312
Rubella: Prevention
live-attenuated vaccine (should not be given to immunocompromised or pregnant patients)
313
RNA viruses with reverse transcriptase
Retroviridae
314
Converts ssRNA viral genome into viral dsDNA
reverse transcriptase
315
Enveloped virus with 2 copies (diploid) of a ssRNA, (+) polarity, most complex retrovirus, many serotypes
Human Immunodeficiency Virus (HIV)
316
HIV: Transmembrane protein (TM) which is linked to a surface protein (SU)
fusion protein (gp41)
317
HIV: Attachment protein
gp120
318
HIV: Cone-shaped, icosahedral core containing the major capsid protein
CA (p24) - diagnosis
319
HIV: Directs entry of dsDNA provirus into the nucleus and is later essential for the process of virus assembly
MA (p17)
320
HIV: RNA is tightly packed with basic protein in a nucleocapsid structure that differs in morphology among diffent retrovirus genera
NC (p7)
321
HIV Genes: p24, p7, p17
gag
322
HIV Genes: Nucleocapsid, Matrix
gag
323
HIV Genes: Reverse transcriptase, Protease, Integrase
pol
324
HIV Genes: gp120, gp41
env
325
HIV Proteins: gag
p24, p7, p17
326
HIV Proteins: nucleocapsid
p24, p7
327
HIV Proteins: matrix
p17
328
HIV Proteins: pol
reverse transcriptase, protease, integrase
329
HIV Proteins: Transcribes RNA genome into DNA
reverse transcriptase
330
HIV Proteins: Cleaves precursor polyeptides
protease
331
HIV Proteins: Integrates viral DNA into host cell DNA
integrase
332
HIV Proteins: env
gp120, gp41
333
HIV Proteins: Attachment to CD4 protein, antigenicity changes rapidly
gp120
334
HIV Proteins: Fusion with host cell
gp41
335
HIV: Group-specific antigen, core, not known to vary, antibodies against this do not neutralize infectivity but serve as important serologic markers of infection
p24
336
HIV: Interacts with the CD4 receptor, mutates rapidly because of lack of editing, many antigenic variants, V3 - most immunogenic region, antibody neutralizes infectivity
gp120
337
HIV: Mediates fusion of the viral envelope with the cell membrane
gp41
338
HIV Genes: Activation of transcription of viral genes
tat
339
HIV Genes: Transport of late mRNAs to cytoplasm
rev
340
HIV Genes: Decreases CD4 and class I MHC proteins
nef
341
HIV Genes: Enhances hypermutation
vif
342
HIV Genes: Transport in non-dividing cells
vpr
343
HIV Genes: Enhances virion release
vpu
344
HIV: Transmission
originally from chimpanzees, transfer of body fluids, transplacental, perinatal, needlestick, sexual contact
345
Preferentially infects and kills helper (CD4) T lymphocytes, loss of cell-mediated immunity, high probability of opportunistic infections, main immune response consists of cytotoxic (CD8) T-lymphocytes
HIV
346
HIV Phases: Acquired through sexual contact, blood, perinatally
Phase 0 - Infection
347
HIV Phases: Rapid viral replication but HIV test is (-)
Phase 1 - Window Period
348
HIV Phases: Peak of viral load, (+) HIV test, mild flu-like illness lasting 1-2 weeks
Phase 2 - Seroconversion
349
HIV Phases: Asymptomatic, CD4 goes down, lasts 1-15 years
Phase 3 - Latent Period
350
HIV Phases: CD4 500-200, lasts 5 years, mild mucocutaneous, dermatologic and hematologic illness
Phase 4 - Early Symptomatic
351
HIV Phases: CD4 < 200, lasts 2 years, AIDS-defining illnesses develop
Phase 5 - AIDS
352
AIDS-Defining Illnesses: CD4 < 500
M. tuberculosis (disseminated TB), HSV (eophagitis), C. albicans (esophageal candidiasis), HHV-8 (Kaposi's sarcoma)
353
AIDS-Defining Illnesses: CD4 < 200
P. jiroveci (PCP pneumonia), T. gondii (cerebral toxoplasmosis), C. neoformans (meningoencephalitis), C. immitis (coccidioidomycosis), C. parvum (chronic diarrhea)
354
AIDS-Defining Illnesses: CD4 < 50
M. avium (invasive pulmonary disease), H. capsulatum (histoplasmosis), CMV (retinitis)
355
Most common AIDS-defining illnesses
P. carinii pneumonia (PCP), esophageal candidiasis, wasting, Kaposi's sarcoma, disseminated MAC
356
Most common among AIDS-defining illnesses
P. carinii pneumonia (PCP)
357
HIV: Presumptive Diagnosis
ELISA
358
HIV: Definitive Diagnosis
Western Blot (gp41, p24)
359
HIV: Treatment
Highly Active Antiretroviral Therapy (HAART)
360
2 nucleoside inhibitors (Zidovudine, Lamivudine) and protease inhibitor (Indinavir), immune reconstitution syndrome in patients co-infected with HBV, HCV, MAC/MAI
Highly Active Antiretroviral Therapy (HAART)
361
HIV: General Prevention
condoms, not sharing needles, proper blood disposal, post-exposure prophylaxis
362
HIV: Perinatal Prevention
perinatal prophylaxis, CS delivery, breastfeeding cessation
363
Retrovirus causing adult T-cell leukemia and a HTLV-associated myelopathy, malignant T-calls with flower-shaped nucleus
Human T-cell Lymphotropic Virus (HTLV)
364
Thread-like virus, longest virus, outbreak of hemorrhagic fever in Zaire (1976), 100% mortality rate
Ebola Hemorrhagic Fever
365
Flavivirus, bird-mosquito-man cycle, initial self-limited febrile illness with progression to neuroinvasive disease
West Nile Fever
366
Flavivirus, most common cause of epidemic encephalitis, most prevalent in SEA, transmitted by Culex mosquitoes, thalamic infarcts on CT scan
Japanese B Encephalitis
