Viruses Flashcards
(439 cards)
1
Q
HIV family
A
retroviridae
2
Q
HIV structure
A
ss(+)RNA, enveloped, truncated conical capsid
3
Q
HIV entry
A
viral gp120 protein binds to target CD4 and co-receptors CCR5 (macrophages) and CXCR4 (T-cells)
viral gp41 transmembrane protein for membrane fusion
4
Q
HIV replication
A
viral reverse transcriptase (RNA dependent DNA polymerase) viral integrase (viral DNA integration into host DNA)
5
Q
HIV assembly/egress
A
translation makes proteins, viral protease cleaves viral polyprotein
6
Q
HIV genes
A
env gene- gp120 and gp41
gag gene- capsid protein and matrix protein
pol gene- RT, protease, integrase
7
Q
HIV transmission
A
sexual contact, bloodborne, vertical (maternal-infant)
8
Q
HIV clinical course
A
acute retroviral syndrome (flu-like), then asymptomatic
stages 1-3 depending on CD4+ T-cell counts (<200 is stage 3/AIDS)
9
Q
HIV tip offs
A
fatigue, wt loss, lymphadenopathy, low grade fever, homosexual male, IV drug user, sexually active adult, decreased CD4 count, opportuinstic infections
10
Q
AIDS prophylaxis
A
CD4 <200 = start pneumocystitis pneumonia (PCP) prophylaxis with TMP-SMX
CD4 <100 = start toxoplasmosis prophylaxis with TMP-SMX
CD4 <50 = start mycobacterium avlum complex (MAC) prophylaxis with azithromycin or clarithromycin
11
Q
HIV testing
A
antigen/antibody tests: p24 AND anti HIV-1/HIV-2 IgM and IgG
CD4+ counts assess progression
10-33 day window period before HIV can be detected
12
Q
HIV treatment
A
treat everyone with HIV; need continued treatment!!
nucleoside reverse transcriptase inhibitors (NRTIs)- binds reverse transcriptase at normal site of nucleoside
non-nucleoside reverse transcriptase inhibitors (NNRTIs)- binds reverse transcriptase elsewhere
integrase inhibitors (—tegravir)
protease inhibitors (–navir)
fusion inhibitors
13
Q
HIV vaccines
A
none
14
Q
HSV-1/2 family
A
herpesviridae
15
Q
HSV-1/2 structure
A
dsDNA, enveloped, icosahedral
16
Q
HSV-1/2 entry
A
tegument proteins unique to herpesviruses
17
Q
HSV-1/2 replication
A
latency- alphaherpesvirus subfamily = neurotrophic
thymidine kinase- helps with early viral DNA replication by turning nucleosides into nucleotides by adding a phosphate group
18
Q
HSV-1/2 assembly/egress
A
virus envelope comes from nuclear membrane
19
Q
HSV-1/2 biology notes
A
reactivation from latency can occur by UV radiation, hyperthermia, stress and IMMUNOSUPPRESSION
T cell response is critical to control
20
Q
HSV-1/2 epidemiology
A
most common cause of viral encephalitis
21
Q
HSV-1/2 transmission
A
close personal contact (kissing, sexual contact), vertical
22
Q
HSV-1/2 clinical course
A
HSV-1- cold sores, latent in trigeminal ganglion
HSV-2- painful genital vesicles, fever, malise, latent in sacral nerve ganglia
both- can cause encephalitits with focal temporal lesions, as well as severe neonatal herpes
23
Q
HSV-1/2 testing
A
clinical diagnosis of characteristic lesions
encephalitis- CSF PCR
genital/skin lesions- PCR or immunoflourescence staining - Tzanck smear of vesicles, look for Cowdry inclusions
24
Q
HSV-1/2 treatment
A
acyclovir (guanosine analog)- viral thymidine kinase converts acyclovir into a false nucleotide to block DNA synthesis by DNA polymerase
25
HSV-1/2 vaccine
none
26
varicella zoster virus (VZV) family
herpesviridae --> HHV-3
27
varicella zoster virus (VZV) structure
dsDNA, enveloped, icosahedral
28
varicella zoster virus (VZV) entry
tegument proteins unique to herpesviruses
29
varicella zoster virus (VZV) replication
latency- alphaherpesvirus subfamily = neurotropic
latent in dorsal root ganglion
thymidine kinase
30
varicella zoster virus (VZV) assembly/egress
virus envelope from nuclear membrane
31
varicella zoster virus (VZV) transmission
respiratory droplets from patient with chickenpox (very contagious)
contact with lesions from patients with shingles (not particularly contagious)
32
varicella zoster virus (VZV) clinical course
congenital varicella
chicken pox (primary infection)- asynchronous vesicular rash (lesions in different stages), fever, pharyngitis, malise, rhinitis, Raye syndrome
shingles- reactivation of latent VZV, pain/vesicles in dermatomal distribution, Ramsay hunt syndrome, herpes zoster ophthamicus
can cause severe disease in immunocompromised- pneumonia
33
varicella zoster virus (VZV) testing
PCR
| old school = Tzanck smear of vesicle, look for Cowdry inclusions
34
varicella zoster virus (VZV) treatment
acyclovir (guanosine analog)- resistance if viral TK acquires mutation
35
varicella zoster virus (VZV) vaccines
live attenuated vaccine for all children
| new inactivated VZV vaccine
36
cytomegalovirus (CMV) family
herpesviridae --> HHV-5
37
cytomegalovirus (CMV) structure
dsDNA, enveloped, icosahedral
38
cytomegalovirus (CMV) entry
receptor cellular integrins (heparan sulfate)
39
cytomegalovirus (CMV) replication
latency- betaherpesvirus subfamily = lymphotropic
| thymidine kinase
40
cytomegalovirus (CMV) assembly/egress
virus envelope from nuclear membrane
41
cytomegalovirus (CMV) biology notes
infected cells have "owl eye" inclusions
| latency in mononuclear cells
42
cytomegalovirus (CMV) transmission
saliva, sexual, blood products, vertical
43
cytomegalovirus (CMV) clinical course
- mononucleosis (monospot negative)
- most common cause of congenital infection- most asymptomatic, severe with jaundice, thrombocytic purpura (blueberry muffin), pneumonitis, CNS damage
- immunocompromised/AIDS/transplant pt- CMV retinitis, interstitial pneumonitis, GI disease/esophagitis/colitis
44
cytomegalovirus (CMV) testing
PCR of blood, test urine in babies only
| **screen blood and organ donors for CMV infection
45
cytomegalovirus (CMV) treatment
gancyclovir (guanosine analog)- used only for CMV and not HSV-1/2
cidofovir and foscarnet (viral DNA polymerase inhibitors)
46
cytomegalovirus (CMV) vaccine
none
47
human herpesvirus 6/7 (HHV 6/7) family
herpesviridae
48
human herpesvirus 6/7 (HHV 6/7) structure
dsDNA, enveloped, icosahedral
49
human herpesvirus 6/7 (HHV 6/7) entry
tegument proteins unique to herpesviruses
50
human herpesvirus 6/7 (HHV 6/7) replication
latency- betaherpesvirus subfamily = lymphotropic, latency in mononuclear cells
HHV 6 infects CD4+ T-helper cells
51
human herpesvirus 6/7 (HHV 6/7) assembly/egress
virus envelope form nuclear membrane
52
human herpesvirus 6/7 (HHV 6/7) transmission
respiratory droplets
53
human herpesvirus 6/7 (HHV 6/7) epidemiology
human reservoir
54
human herpesvirus 6/7 (HHV 6/7) clinical course
roseola- fever for 5 days, fever resolves followed by lacy body rash that spares the face --> caused commonly by HHV 6 (7 is less common)
high fever can cause seizures
one of the 5 classic childhood exanthems
55
human herpesvirus 6/7 (HHV 6/7) testing
clinical
56
human herpesvirus 6/7 (HHV 6/7) treatment
supportive
57
human herpesvirus 6/7 (HHV 6/7) vaccine
none
58
epstein-barr virus (EBV) family
herpesviridae --> HHV-4
59
epstein-barr virus (EBV) structure
dsDNA, enveloped, icosahedral
60
epstein-barr virus (EBV) entry
binds receptor CD21 (complement receptor 2)
61
epstein-barr virus (EBV) replication
latency- gammaherpesvirus subfamily = oncogenic
| latent in B cells
62
epstein-barr virus (EBV) assembly/egress
virus envelope from nuclear membrane
63
epstein-barr virus (EBV) epidemiology
reservoir in humans
64
epstein-barr virus (EBV) transmission
respiratory secretions, saliva
65
epstein-barr virus (EBV) clinical course
mononucleosis (heterophile positive)- fatigue, fever, sore throat, lymphadenopathy, splenomegaly
lymphoproliferative disease in immunocompromised and cancer patients
lymphoma, nasopharyngeal carcinoma
Downey type 2 atypical lymphocytes up to 70% in blood
66
epstein-barr virus (EBV) testing
heterophile antibodies positive
| PCR of blood
67
epstein-barr virus (EBV) treatment
supportive
68
epstein-barr virus (EBV) vaccines
none
69
HHV-8 family
herpesviridae --> kaposi sarcoma-associated herpesvirus
70
HHV-8 structure
dsDNA, enveloped, icosahedral
71
HHV-8 replication
latency- gammaherpesvirus subfamily = oncogenic
| latency in B cells and glandular epithelial cells
72
HHV-8 assembly/egress
virus envelope from nuclear membrane
73
HHV-8 biology notes
gene turns on vascular endothelial growth factor (VEGF) --> leads to kaposi sarcoma
74
HHV-8 epidemiology
reservoir in humans
75
HHV-8 transmission
sexual contact, saliva, vertical, transplantation
76
HHV-8 clinical course
kaposi sarcoma- neoplasm of endothelial cells
seen in HIV/AIDS and transplant patients
dark plaques/nodules on skin
can affect GI tract and lungs
classic kaposi sarcoma- seen in elderly men, most often affects skin of the extremities
77
HHV-8 testing
antibody tests, PCR
78
HHV-8 treatment
no drugs, surgical, try to correct immunosuppression
79
HHV-8 vaccines
none
80
molluscum contagiosum family
poxiviridae
81
molluscum contagiosum strucure
dsDNA, enveloped, complex morphology, HUGE
82
molluscum contagiosum replication
replicates in the cytoplasm
83
molluscum contagiosum assembly/egress
makes its own envelope
84
molluscum contagiosum epidemiology
reservoir in humans
85
molluscum contagiosum transmission
direct contact, fomites
86
molluscum contagiosum clinical course
flesh colored papule with central umbilication
87
molluscum contagiosum testing
eosinophillic cytoplasmic inclusion bodies on biopsy
88
molluscum contagiosum treatment
supportive, disease is usually self-limited
treat underlying HIV
cimetidine as immune stimulant in children (histamine receptor antagonist--> stimulates delayed type hypersensitivity immunologic reaction)
89
molluscum contagiosum vaccines
none
90
variola (smallpox) family
poxviridae
91
variola (smallpox) structure
dsDNA, enveloped, complex morphology, HUGE
92
variola (smallpox) replication
replicates in the cytoplasm
93
variola (smallpox) epidemiology
eradicated using vaccine
94
variola (smallpox) transmission
respiratory transmission
95
variola (smallpox) clinical course
flu-like prodome followed by vesicular rash, mouth to extremities, can cover whole body in a day
synchronous rash- all vesicles are in the same stage (unlike chicken pox)
96
variola (smallpox) treatment
supportive
97
variola (smallpox) vaccine
live attenuated vaccine --> causes serious complications for immunocompromised patients and is not safe for pregnant women
98
human papilloma virus (HPV) family
papillomavirus
99
human papilloma virus (HPV) structure
dsDNA, naked, icosahedral
100
human papilloma virus (HPV) replication
replicates in the nucleus like all DNA viruses except pox
101
human papilloma virus (HPV) assembly/egress
infects basal layer of the skin/mucus membranes (has tropism)
malignacyl viral proteins E6 and E7 inhibit tumor suppressor genes p53 and Rb (respectively)
102
human papilloma virus (HPV) epidemiology
reservoir in human
103
human papilloma virus (HPV) transmission
direct contact, fomites
104
human papilloma virus (HPV) clinical course
```
cutaneous warts mostly on hands (serotype 2&4)
plantar warts on soles of feet, deep and painful (serotype 1)
anogenital warts (condyloma acuminata) (serotype 6&11)
anal, vaginal, vulvar, penile and laryngeal cancer
```
105
human papilloma virus (HPV) testing
koilocytic cells in pap smear, PCR
106
human papilloma virus (HPV) treatment
cidofovir (antiviral), surgical, chemical, immune
107
human papilloma virus (HPV) vaccine
cancer vaccine, gardasil (inactivated subunit vaccine)
| safe sex is important for protection
108
parvovirus B19 family
parvoviridae
109
parvovirus B19 structure
ssDNA (**only ssDNA virus), naked, icosahedral
110
parvovirus B19 entry
receptor is the P antigen on RBCs
111
parvovirus B19 replication
replicates in nucleus like all DNA viruses except pox
112
parvovirus B19 assembly/egress
infects immature erythroid progenitor cells causing lysis
| can cause aplastic crisis in pts with sickle cells
113
parvovirus B19 epidemiology
human respiratory tract
114
parvovirus B19 transmission
respiratory, fomites, vertical
115
parvovirus B19 clinical course
childhood exanthem- flu-like symptoms followed by raised, indurated facial rash
arthralgias in adults
myocarditis in adults and children
fetus with severe anemia, heart failure, hydrops fetalis, spontaneous abortion
116
parvovirus B19 testing
antibody testing, PCR
117
parvovirus B19 treatment
supportive
118
parvovirus B19 vaccine
none
119
yellow fever virus family
flaviviridae
120
yellow fever virus strucutre
ss(+)RNA, enveloped, icosahedral
121
yellow fever virus replication
cytoplasmic, genome closely matches mRNA
122
yellow fever virus epidemiology
```
arthropod borne (arbovirus)
mosquito vector, human and monkey reservoir
```
123
yellow fever virus transmission
mosquito bite
124
yellow fever virus clinical course
high fever, back pain, black vomitus, bloody stools, GI, liver, kidney and heart damage
jaundice
125
yellow fever virus testing
councilman bodies on liver biopsy (represents hepatocytes undergoing apoptosis)
126
yellow fever virus treatment
supportive
127
yellow fever virus vaccine
live attenuated vaccine
| vector control is important in disease control
128
dengue virus family
flavivirus
129
dengue virus structure
ss(+)RNA, enveloped, icosahedral
130
dengue virus replication
cytoplasmic, genome closely matches mRNA
| infects WBCs
131
dengue virus epidemiology
arthropod borne (arbovirus), mosquito vector, human and monkey reservoir
132
dengue virus transmission
mosquito bite
133
dengue virus clinical course
breakbone fever- rash, muscle and joint pain, retro-orbital headache, high fever
dengue hemorrhagic shock
thrombocytopenia and leukopenia on CBC
134
dengue virus treatment
supportive
135
dengue virus vaccine
limited usefulness, can make dengue fever worse in naive patients
136
dengue virus control notes
**antibody dependent enhancement --> once you get it once it gets worse the second time you get it
137
zika virus family
flaviviridae
138
zika virus structure
ss(+)RNA, enveloped, icosahedral
139
zika virus replication
cytoplasmic, genome closely matches mRNA
140
zika virus epidemiology
arthropod borne (arbovirus), mosquito vector, vertebrate reservoir
141
zika virus transmission
mosquito, sexual, vertical
142
zika virus clinical course
febrile illness with itchy rash and arthralgia, joint pain, conjunctivitis
usually mild and in most people asymptomatic
congenital- microcephaly, fetal demise
143
zika virus testing
PCR detection of viral RNA, antibody test
144
zika virus treatment
supportive
145
zika virus vaccine
none, vector control is important in disease control
146
rubella virus family
togaviridae
147
rubella virus structure
ss(+)RNA, enveloped, icosahedral
148
rubella virus replication
cytoplasmic replication
149
rubella virus epidemiology
respiratory droplets, human reservoir
150
rubella virus transmission
respiratory, vertical
151
rubella virus clinical course
```
german measles (class childhood exanthem)
erythematous rash starts on face, proceeds to trunk, does not coalesce (vs measles)
postauricular and occipital lymphadenopathy
congenital rubella syndrome- fetus with cataracts, heart defects, developmental delay, hearing loss
```
152
rubella virus testing
antibody testing
| screen all pregnant women for rubella immunity
153
rubella virus treatment
supportive
154
rubella virus vacine
live attenuated MMR vaccine- do give it to children, do NOT give it to pregnant women or immunocompromised
155
measles virus family
paramyxoviridae, also called rubeola virus
156
measles virus structure
ss(-)RNA, non-segmented, enveloped, helical
157
measles virus entry
fusion proteins appear as spikes on virus surface (F proteins)
158
measles virus replication
cytoplasmic replication
| (-) RNA so needs a viral RNA dependent RNA polymerase protein that is viron associated
159
measles virus assembly/egress
buds from cell membrane
160
measles virus biology notes
causes cell-cell fusion to make giant cells
can escape immune detection
hemaglutinin is a virulence factor (clumps RBCs)
161
measles virus epidemiology
human reservoir
162
measles virus transmission
respiratory droplets
163
measles virus clinical course
4 C's- cough, coryza, conjunctivitis, koplik spots on buccal mucosa
classic childhood exanthem of erythematous rash that starts on the head and progresses downward; rash can become confluent (unlike rubella)
complications- pneumonia, encephalitis, acute disseminated encephalomyelitis, subacute sclerosing panencephalitis
164
measles virus testing
antibody testing
165
measles virus treatment
supportive, vitamin A
166
measles virus vaccine
live attenuated MMR
167
mumps virus family
paramyxoviridae
168
mumps virus structure
ss(-)RNA, non-segmented, enveloped, helical, filamentous morphology
169
mumps virus entry
fusion proteins appear as spikes on virus surface (F proteins) --> F proteins cause cell-cell fusion to make giant cells
170
mumps virus replication
cytoplasmic replication
| (-) RNA so needs a viral RNA dependent RNA polymerase protein that is virion associated
171
mumps virus assembly/egress
buds from cell membrane
172
mumps virus biology notes
can escape immune detection
hemagglutinin is a virulence factor (clumps RBCs)
neuraminidase is a virulence factor (allows for viral release from host cell)
173
mumps virus epidemiology
respiratory droplets, human reservoir
174
mumps virus transmission
respiratory
175
mumps virus clinical course
mumps- bilateral parotitis with fever, headache, malise
complications include orchitis (testicular inflammation), pancreatitis and meningioencephalitis
can cause sterility, especially if contracted after puberty
176
mumps virus testing
antibody testing
multinucleated giant cells (caused by F proteins) on microscopy
hemagglutination on assay
177
mumps virus treatment
supportive
178
mumps virus vaccine
live attenuated MMR vaccine --> do give to children, do NOT give to pregnant women or immunocompromised, patients with HIV should be vaccinated if their CD4+ count is >200
179
ebola virus family
filoviridae
| marburg virus = another filovirus that causes the same disease
180
ebola virus structure
ss(-)RNA, enveloped, helical, filamentous morphology
181
ebola virus replication
cytoplasmic replication
| (-) RNA so needs a viral RNA dependent RNA polymerase protein that is virion associated
182
ebola virus epidemiology
arthropod-borne (arbovirus), mosquito vector, human and bat reservoir
183
ebola virus transmission
mosquito bite
contact with bodily fluids, fomites, dead bodies, infected bats/apes/monkeys
health care workers are at very high risk
184
ebola virus clinical course
flu-like illness then fatigue, headaches, vomitting/diarrhea (fluid loss), bleeding by stool/mucosa, can have massive hemmorrhage, shock
rash and meningoencephalitis
185
ebola virus disease notes
incubation period of 6-12 days (can be up to 21)
186
ebola virus testing
rapid antigen test, PCR
187
ebola virus treatment
supportive
188
ebola virus vaccine
none; strict isolation of pts, travel restrictions, extreme isolation in healthcare settings to prevent spread
189
JC and BK virus family
polyomavirus
190
JC and BK virus structure
dsDNA
191
JC and BK virus replication
replicates in nucleus like all DNA viruses except pox
192
JC and BK virus biology notes
JC infects oligodendrocytes = demyelination
| BK infects kidney
193
JC and BK virus epidemiology
most people are infected with these viruses, usually harmless
disease in immunocompromised
194
JC and BK virus transmission
JC- respiratory
| BK- urine
195
JC and BK virus clinical course
JC and progressive multifocal leukoencephalopathy (PML)- transplant or AIDS pt with progressive deterioration in mental function (due to inflammed/destroyed oligodendrocytes), usually fatal; clumsiness, progressive weakness and visual, speech and personality changes
BK and kidney disease- usually kidney transplant recipient with renal dysfunction and inflammation; causes nephropathy and kidney/urinary tract issues, hemorrhagic cystitis (manifests as blood in urine)
196
JC and BK virus testing
PCR, antibody testing, PML will have characteristic MRI findings
197
JC and BK virus treatment
supportive, reduce immunosupression
198
JC and BK virus vaccines
none
199
polio virus family
picornaviridae --> enterovirus
200
polio virus structure
ss(+)RNA, non-segmented, naked, icosahedral
201
polio virus entry
receptor CD155
202
polio virus replication
cytoplasmic replication
| (+) RNA, RNA dependent RNA polymerase
203
polio virus biology notes
resistant to alcohol and detergents -->acid stable
| 3 polio serotypes (PV1, PV2, PV3)
204
polio virus epidemiology
human reservoir only, strictly human pathogen
205
polio virus transmission
fecal-oral transmission (enters GI tract)
206
polio virus clinical course
often asymptomatic infection
| fever, aseptic meningitis, paralytic polio (flaccid paralysis, asymmetric, no sensory loss)
207
polio virus disease notes
virus targets anterior horn motor neurons
208
polio virus testing
antibody test
209
polio virus treatment
supportive
210
polio virus vaccines
3 strains
- live vaccine (sabin)- results in IgG response, no risk of reverting to infectious form, preferred
- killed vaccine (salk)- results in IgG and IgA response, shed in the feces (transmissible via fecal oral route)
- activated vaccine (OPV)- by mouth, inactivated (IPV) by injection
OPV with vaccine associated paralytic poliomyelitis
herd protection- protection of unvaccinated by cocooning or being surrounded by vaccinated persons
herd immunity- actual transmission of attenuated vaccine strains to confer immunity
211
west nile virus family
flaviviridae
212
west nile virus structure
ss(+)RNA, enveloped, icosahedral
213
west nile virus replication
cytoplasmic, genome closely matches mRNA
214
west nile virus epidemiology
arthropod borne (arbovirus) like most flaviviruses in humans, mosquito vector, bird reservoir
215
west nile virus transmission
mosquito bite
216
west nile virus clinical course
west nile fever- fever, headache, myalgias, V/D, rash, stiff neck (meningitis)
summer encephalitis- disorientation/confusion, stupor/coma, tremors, seizures, partial paralysis or weakness
muscle weakness can be permanent
**viral encephalitis accompanied by flaccid paralysis
217
west nile virus testing
antibody test (blood and CSF), CSF PCR
218
west nile virus treatment
supportive
219
west nile virus vaccines
none, vector control is important in disease control
220
st. louis encephalitis virus family
flavivirus
221
st. louis encephalitis virus structure
ss(+)RNA, enveloped, icosahedral
222
st. louis encephalitis virus replication
cytoplasmic, genome closely matches mRNA
223
st. louis encephalitis virus epidemiology
arthropod-borne (arbovirus) like most flaviviruses, mosquito vector, bird reservoir
224
st. louis encephalitis virus transmission
mosquito bites
225
st. louis encephalitis virus clinical course
most infections are just mild illnesses
fever, headache, neck stiffness (meningitis)
summer encephalitis- disorientation/confusion, stupor/coma, tremors, seizures, spastic paralysis, can be fatal
226
st. louis encephalitis virus testing
antibody test (blood and CSF)
227
st. louis encephalitis virus treatment
supportive
228
st. louis encephalitis virus vaccine
none; vector control is important in disease control
229
japanese encephalitis virus family
flavivirus
230
japanese encephalitis virus structure
ss(+)RNA, enveloped, icosahedral
231
japanese encephalitis virus replication
cytoplasmic, genome closely matches mRNA
232
japanese encephalitis virus epidemiology
```
arthropod borne (arbovirus), mosquito vector, bird and pig reservoir, common in south/east/southeast asia
leading cause of viral encephalitis in asia
```
233
japanese encephalitis virus transmission
mosquito bite
234
japanese encephalitis virus clinical course
most infections are asymptomatic
fever, headache, malaise, severe rigors, neck rigidity, hemiparesis, seizures, brain damage with neurodevelopmental delay, deafness and hemiparesis can persist
235
japanese encephalitis virus testing
antibody test (blood and CSF)
236
japanese encephalitis virus treatment
supportive
237
japanese encephalitis virus vaccine
live attenuated and inactivated vaccines available in endemic areas; vector control is important in disease control
238
alphaviruses examples
eastern equine encephalitis, western equine encephalitis, venezuelan equine encephalitis, chikungunya virus
239
alphaviruses family
togavirus
240
alphaviruses structure
ss(+)RNA, enveloped, icosahedral
241
alphaviruses replication
cytoplasmic replication
242
alphaviruses epidemiology
arboviruses
equine encephalitis group- mosquitoes and horses
chikungunya- mosquitoes and primates, birds, rodents
243
alphaviruses transmission
mosquito bites
244
alphaviruses clinical course
encephalitis (EEEV very bad, WEEV milder)
| chikungunya causes fever, joint pain, headache, rash; doesn't really cause encephalitis
245
alphaviruses testing
antibody testing
246
alphaviruses treatment
supportive
247
alphaviruses vaccines
none
248
california encephalitis virus family
bunyavirus
249
california encephalitis virus structure
ss(-)RNA, 3 segments, enveloped, helical
250
california encephalitis virus replication
cytoplasmic replication
| (-)RNA so needs a viral RNA dependent RNA polymerase protein that is virion associated
251
california encephalitis virus epidemiology
arthropod borne (arbovirus)
252
california encephalitis virus transmission
mosquito bite
253
california encephalitis virus clinical course
most infections are just mild illness
fever, headache, neck stiffness (meningitis)
summer encephalitis- disorientation/confusion, stupor/coma, tremors, seizures, paralysis, can be fatal
254
california encephalitis virus testing
PCR
255
california encephalitis virus treatment
supportive
256
california encephalitis virus vaccine
none
257
rabies virus family
rhabdovirus
258
rabies virus structure
ss(-)RNA, non-segmented, enveloped, helical, bullet shaped
259
rabies virus entry
receptor the nicotinic AChR (ascetylcholine receptor)
260
rabies virus replication
cytoplasmic, genome closely matches mRNA
261
rabies virus epidemiology
US most cases are wild animals (bats, raccoons, foxes, skunks), but worldwide is mostly dogs
262
rabies virus transmission
bite or contact with infected animal
263
rabies virus clinical course
starts with flu-like illness, then neurological symptoms of hydrophobia, seizures, disorientation, hallucination, coma and death
264
rabies virus testing
negri bodies (intracytoplasmic inclusion bodies on path of brain biopsy), DFA of smears of corneal epithelial cells, PCR
265
rabies virus treatment
supportive for advanced disease
| immunotherapy in suspected disease
266
rabies virus vaccine
after bite give 1 dose human rabies immunoglobulin (hRIB) and 4 dose series of rabies vaccine
killed virus vaccine
vaccine for high risk people and for domestic animals
267
lymphocytic choriomeningitis virus (LCV) family
arenavirus
268
lymphocytic choriomeningitis virus (LCV) structure
ssRNA, ambisense, segmented, enveloped, helical nucleocapsid
269
lymphocytic choriomeningitis virus (LCV) replication
cytoplasmic replication, needs virion-associated polymerase
| ambisense- RNA strands code proteins in both reading directions
270
lymphocytic choriomeningitis virus (LCV) epidemiology
RODENTS!! mice are the reservoir
271
lymphocytic choriomeningitis virus (LCV) transmission
contact with mice/hamsters, transmission via aerosolized particles of rodent urine, feces or saliva, or by ingesting contaminated food
272
lymphocytic choriomeningitis virus (LCV) clinical course
2 phase disease- starts with fever, headache, malaise, muscle pain, n/v, sore throat, parotid pain; then better, the second phase of aseptic meningitis or encephalitis (stiff neck, fever, headache, confusion)
congenital LCMV- can lead to spontaneous abortions, brain abnormalities, optic abnormalities, neurological deficits
273
lymphocytic choriomeningitis virus (LCV) testing
antibody test, PCR of CSF
274
lymphocytic choriomeningitis virus (LCV) treatment
supportive
275
lymphocytic choriomeningitis virus (LCV) vaccine
none; mice (vector) control to help control disease
276
influenza A/B family
orthomyxovirus
277
influenza A/B structure
ss(-)RNA, segmented, enveloped, helical, hemagglutinin and neuraminidase proteins on surface
278
influenza A/B entry
hemagglutinin glycoprotein mediates binding to cell and entry
279
influenza A/B replication
RNA virus that replicates nucleic acid in nucleus (***an exception)
M2 protein- allows for uncoating of the virus
280
influenza A/B assembly/egress
neuraminidase glycoprotein involved in the release of progeny virus from cells, cleaves sugars that bind mature virus particles (--> good target for drugs)
281
influenza A/B epidemiology
influenza A- reservoir in birds, pigs, humans (shift and drift)
influenza B- reservoir in humans only (no shift, just drift)
282
influenza A/B transmission
respiratory droplets, direct contact, fomites
283
influenza A/B clinical course
headache, malaise, fever, chills, myalgias, anorexia
in younger children- bronchiolitis, croup, otitis media, vomitting
pneumonia- secondary bacterial infections
complicated by Reye syndrome (encephalopathy with liver toxicity- NO ASPIRIN) or guillain barre syndrome
284
influenza A/B testing
rapid antibody/antigen testing, PCR of nasal secretions
285
influenza A/B treatment
amantadine/rimantadine (inhibit viral uncoating)
| zanamavir/oseltamivir (neuraminidase inhibitors)
286
influenza A/B vaccines
killed vaccine (recommended), live attenuated vaccine
287
adenovirus family
adenovirus
288
adenovirus structure
dsDNA, naked, icosahedral
289
adenovirus entry
entry via endosome
290
adenovirus replication
replicates in the nucleus
early and late genes (early ones are regulatory proteins)
early gene E1A binds retinoblastoma tumor suppressor to cause cancer in animals (not currently known to cause cancer in humans though)
291
adenovirus biology notes
can be lytic in permissive cells, can be latent or oncogenic in non-permissive cells
292
adenovirus epidemiology
ubiquitous in humans/animals, very stable, prolonged survival in the envrionment
293
adenovirus transmission
respiratory, fecal/oral (naked), direct contact
294
adenovirus clinical course
acute respiratory disease and pneumonia in spring/winter
pharyngoconjunctival fever (pharyngitis & conjunctivitis/ pink eye) with lymphadenopathy, cough, sore throat
"pool fever"
acute hemorrhagic cystitis usually boys 5-15 with dysuria and hematuria
myocarditis
295
adenovirus testing
antibody testing
296
adenovirus treatment
cidofovir (viral DNA polymerase inhibitor) for very immunocompromised pts
mostly just supportive care
297
adenovirus vaccine
oral vaccine given to military recruits (live non-attenuated vaccine)
298
coxsackievirus A family
picornavirus --> enterovirus
299
coxsackievirus A structure
ss(+)RNA, non segmented, naked, icosahedral
300
coxsackievirus A replication
cytoplasmic replication, acid stable
301
coxsackievirus A transmission
fecal-oral
302
coxsackievirus A clinical course
skin/mucous membranes- herpanginia (painful mouth blisters), acute hemorrhagic conjunctivitis, hand foot and mouth disease, common cold
fever, rashes, upper respiratory disease, aseptic meningitis
303
coxsackievirus A testing
clinical diagnosis or PCR of nasal swab or blood
304
coxsackievirus A treatment
supportive
305
coxsackievirus A vaccine
none, can prevent by handwashing
306
coxsackievirus B family
picornavirus --> enterovirus
307
coxsackievirus B structure
ss(+)RNA, non segmented, naked, icosahedral
308
coxsackievirus B replication
cytoplasmic
309
coxsackievirus B transmission
fecal-oral
310
coxsackievirus B clinical course
organ involvement- heart, pancreas, liver to cause myocarditis, pericarditis, dilated cardiomyopathy, hepatitis
bornholm disease (devils grip)- pleurodynia (excruciating chest pain)- usually a summer disease
common cold
fever, rashes, upper respiratory disease and aseptic meningitis
311
coxsackievirus B testing
clinical diagnosis or PCR of nasal swab or blood
312
coxsackievirus B treatment
supportive
313
coxsackievirus B vaccine
none, prevent by handwashing
314
echovirus family
picornavirus --> enterovirus; enteric cytopathic human orphan
315
echovirus structure
ss(+)RNA, naked, non segmented, icosahedral
316
echovirus replication
cytoplasmic
317
echovirus epidemiology
disproportionately seen in males and children
318
echovirus transmission
fecal-oral
319
echovirus clinical course
acute febrile illness in infants and young children, often with rash
aseptic meningitis
neonatal sepsis with liver failure and/or myocarditis
myocarditis
320
echovirus testing
clinical diagnosis or PCR of nasal swab or blood
321
echovirus treatment
supportive
322
echovirus vaccine
none, prevent by handwashing
323
rhinovirus family
picornavirus
324
rhinovirus structure
ss(+)RNA, non segmented, naked, icosahedral
325
rhinovirus entry
ICAM-1 cellular receptor (intracellular adhesion molecule 1)
326
rhinovirus replication
cytoplasmic
327
rhinovirus notes
acid labile (destroyed by stomach acid)
328
rhinovirus epidemiology
september to april, people indoors, together in schools
| over 100 serotypes with practically no cross protection between serotypes
329
rhinovirus transmission
respiratory droplets or fomites, can survive for 3 hours outside of human host
330
rhinovirus clinical course
common cold, peaks in summer/fall
| sore throat, rhinorrhea, nasal congestion, cough, mild fever
331
rhinovirus testing
clinical diagnosis or PCR of nasal swab
332
rhinovirus treatment
supportive
333
rhinovirus vaccine
none, can protect by handwashing
334
coronavirus family
coronavirus --> SARS (severe acute respiratory syndrome), MERS (middle eastern respiratory syndrome)
335
coronavirus structure
ss(+)RNA, non segmented, enveloped, helical, HA molecules on viral surface to give shape like sun
336
coronavirus replication
cytoplasmic replication
337
coronavirus epidemiology
coronavirus- common cold, endemic, winter/spring
SARS- bird/small mammal reservoir
MERS- bat and camel reservoir
338
coronavirus transmission
respiratory droplets
| SARS and MERS also in urine, sweat, feces
339
coronavirus clinical course
```
common cold (#2 cause)
SARS/MERS- severe acute respiratory syndrome with atypical pneumonia, fever, flu like illness, dry cough, dyspnea, progressive hypoxia
```
340
coronavirus testing
antibodies, PCR
| travel to endemic areas is important in diagnosis
341
coronavirus treatment
supportive
342
coronavirus vaccines
none
343
respiratory syncytial virus (RSV) family
paramyxovirus
344
respiratory syncytial virus (RSV) structure
ss(-)RNA, non segmented, enveloped, helical
345
respiratory syncytial virus (RSV) entry
F and G proteins on viral surface (target for monoclonal antibodies/prevention)
346
respiratory syncytial virus (RSV) replication
cytoplasmic replication, needs a viral RNA dependent RNA polymerase that is virion associated
347
respiratory syncytial virus (RSV) assembly/egress
buds from cell membrane, restricted to superficial cells of respiratory epithelium
buds at apical membrane (may be a strategy for immune evasion)
348
respiratory syncytial virus (RSV) transmission
direct contact, respiratory transmission
349
respiratory syncytial virus (RSV) clinical course
adults- common cold
infants- bronchiolitis, necrosis of bronchioles, atypical pneumonia (low fever, tachypnea, tachycardia, expiratory wheeze
350
respiratory syncytial virus (RSV) testing
PCR of nasal secretions
351
respiratory syncytial virus (RSV) treatment
supportive
352
respiratory syncytial virus (RSV) vaccines
none, monoclonal antibody palvizumab blocks fusion (F) protein, used for prophylaxis in premature infants and high risk infants
353
parainfluenza viruses 1-4 family
paramyxovirus
354
parainfluenza viruses 1-4 structure
ss(-)RNA, non segmented, enveloped, helical
355
parainfluenza viruses 1-4 replication
cytoplasmic, needs a virion associated RNA dependent RNA polymerase
356
parainfluenza viruses 1-4 transmission
direct contact, respiratory transmission, can remain viable on surfaces for 1 hour
357
parainfluenza viruses 1-4 clinical course
type 1- croup (subglottal swelling, hoarse barking cough)
type 2- croup and other upper/lower respiratory disease
type 3- bronchiolitis, pneumonia
type 4- mild/asymptomatic
immunocompromised can get severe/fatal pneumonia
aseptic meningitis
358
parainfluenza viruses 1-4 testing
PCR of nasal secretions
359
parainfluenza viruses 1-4 treatment
supportive, steroids and nebulizer treatments for croup, ribavirin in severe HPIV-3 in immunocompromised
360
human metapneumovirus family
pneumovirus
361
human metapneumovirus structure
ss(-)RNA, non segmented, enveloped, helical
362
human metapneumovirus replication
cytoplasmic regulation, virion associated RNA dependent RNA polymerase
363
human metapneumovirus transmission
direct contact, respiratory transmission
364
human metapneumovirus clinical course
common cold, reinfections common, severe disease in premature infants and immunocompromised, asthma patients and COPD patients
commonly mistaken for RSV
365
human metapneumovirus testing
PCR of nasal secretions
366
human metapneumovirus treatment
supportive
367
human metapneumovirus vaccines
none
368
hantavirus family
bunyavirus
369
hantavirus structure
ss(-)RNA, enveloped, helical, segmented
370
hantavirus replication
cytoplasmic replication, needs a virion associated RNA dependent RNA polymerase
371
hantavirus epidemiology
contact with rodent saliva, feces, urine; rodent reservoir
372
hantavirus transmission
respiratory route --> rat poop
373
hantavirus clinical course
hemorrhagic fever with renal syndrome- headaches, back abdominal pain, fever, chills, nausea, blurred vision, rash, then low BP, shock, vascular leakage
pulmonary syndrome- often fatal pulmonary disease, flu like symptoms (fever, cough, myalgias, headache, SOB, pulmonary edema)
374
hantavirus testing
PCR
375
hantavirus treatment
supportive
376
hantavirus vaccine
none, control of rodent vectors
377
norwalk virus family
calicivirus --> noro like virus
378
norwalk virus structure
ss(+)RNA, non segmented, naked, icosahedral
379
norwalk virus entry
receptor mediated endocytosis in gut
380
norwalk virus replication
cytoplasmic replication, polyprotein is cleaved by viral proteases
381
norwalk virus epidemiology
most common cause of viral gastroenteritis, 12-48 hour incubation period, common in winter
commonly associated with cruise ships, closed communities, food like shellfish
382
norwalk virus transmission
fecal-oral, person-to-person contact, contaminated surfaces
383
norwalk virus clinical course
n/v, watery diarrhea, abdominal pain, lethargy, weakness, myalgias, fever possible
severe illness is rare and most recover in 2-3 days
384
norwalk virus testing
PCR of stool
385
norwalk virus treatment
supportive
386
norwalk virus vaccine
none, best to use soap and water to prevent
387
rotavirus family
reovirus
388
rotavirus structure
dsRNA, segmented, naked, icosahedral
389
rotavirus entry
receptor mediated endocytosis in gut
390
rotavirus replication
cytoplasmic replication
391
rotavirus biology notes
produces NSP4 toxin- an enterotoxin which increases gut chloride permeability leading to diarrhea
392
rotavirus transmission
fecal-oral, person to person contact, contaminated surfaces, aerosolized
particles can remain viable in water 10-20 days
393
rotavirus clinical course
n/v, watery diarrhea, abdominal pain, subsequent rotavirus illnesses are less severe
394
rotavirus testing
PCR of stool, antigen in stool
395
rotavirus treatment
supportive
396
rotavirus vaccine
live attenuated vaccine recommended for all children
| early vaccines were linked with bowel intussuception
397
hepatitis A virus family
picornavirus
398
hepatitis A virus structure
ss(+)RNA, naked, icosahedral
399
hepatitis A virus replication
cytoplasmic replication
400
hepatitis A virus epidemiology
2-6 week incubation, shellfish, travelers, daycare, human reservoir, NO chronic carriers known
401
hepatitis A virus tranmission
fecal-oral, blood transmission (RARE), men who have sex with men at high risk
402
hepatitis A virus clinical course
often asymptomatic, self limiting
fever, nausea, fatigue, anorexia, diarrhea, abdominal pain, jaundice, dark amber urine, elevated ALT and AST in blood
symptoms can last 2-6 months
smokers develop an aversion to smoking
403
hepatitis A virus testing
antibody test, IgM
404
hepatitis A virus treatment
supportive
405
hepatitis A virus vaccine
inactivated Hep A vaccines in US
406
hepatitis E virus family
hepevirus
407
hepatitis E virus structure
ss(+)RNA, non segmented, naked, icosahedral
408
hepatitis E virus epidemiology
3-8 week incubation, outbreaks after heavy rain/monsoons, domestic animal reservoir (esp pigs)
409
hepatitis E virus transmission
fecal-oral, especially waterborne and also foodborne (contaminated meat)
410
hepatitis E virus clinical course
often acute and self-limiting
fever, nausea, fatigue, anorexia, diarrhea, abdominal pain, jaundice, dark amber urine, fulminant liver failure in pregnant women (especially in 3rd trimester)
elevated AST and ALT in blood
411
hepatitis E virus testing
antibody test, IgM
412
hepatitis E virus treatment
ribavirin?
413
hepatitis E virus vaccine
no effective
414
hepatitis B virus family
hepadnavirus, adenovirus
415
hepatitis B virus structure
DNA, only partially double stranded, enveloped, icosahedral
416
hepatitis B virus entry
entry via endosome
417
hepatitis B virus replication
replicates in nucleus, makes a covalently closed circular DNA form in nucleus, replication in hepatocytes
uses reverse transcriptase
dane particles = infectious virions
418
hepatitis B virus transmission
blood, body fluid, sexual contact, vertical transmission
419
hepatitis B virus clinical course
fever, nausea, fatigue, anorexia, diarrhea, abdominal pain, acute jaundice, dark urine, sometimes causes chronic infection
420
hepatitis B virus testing
antibody testing --> antibodies to various hepatitis B proteins distinguish acute vs. chronic infection
421
hepatitis B virus vaccine
recombinant HBsAg given at birth and series follows
422
hepatitis B virus treatment
nucleoside analog drugs- lamivudine, entecavir, telbivudine, tenofovir, adefovir
423
hepatitis C virus family
flavivirus
424
hepatitis C virus structure
ss(+)RNA, enveloped, icosahedral
425
hepatitis C virus replication
cytoplasmic, genome closely matches mRNA
| error prone polymerase with no 3' to 5' exonuclease activity leads to constant antigen evolution
426
hepatitis C virus transmission
blood borne, IV drug use, transfusions (before '90), needle stick injury, vertical transmission, NOT SEX
427
hepatitis C virus clinical course
fever, nausea, fatigue, anorexia, diarrhea, abdominal pain
jaundice NOT common
chronic infection- mostly no symptoms for several decades but then cirrhosis and liver failure
cryoglobulinemia (aggregates of immunoglobulins that are insoluble at low temperatures)
428
hepatitis C virus testing
antibody tests, PCR of blood, liver biopsy to assess damage
429
hepatitis C virus treatment
protease inhibitors, polymerase inhibitors, direct acting antivirals (interfere with viral enzymes), ribavirin, interferon, treatment is very expensive
430
hepatitis C virus vaccine
none
431
hepatitis D virus family
a viroid or subviral satelite
432
hepatitis D virus structure
ss(-)RNA, self complementary, enveloped, contains hep B proteins in envelope
433
hepatitis D virus entry
via endosome
434
hepatitis D virus replication
no viral polymerase at all, produces one protein (HDAg)- true viroids produce none, can only replicate in HBV infected cells
435
hepatitis D virus transmission
blood, body fluid, sexual contact, pretty much only in patients at high risk for Hep B
436
hepatitis D virus clinical course
more severe complications with hep B and hep D than Hep B alone
liver failure, cirrhosis, liver cancer
coinfection = hep B and hep D together
superinfection = hep D infects after hep B
437
hepatitis D virus testing
antibody testing
438
hepatitis D virus treatment
no specific antivirals, interferons used
439
hepatitis D virus vaccine
vaccine for hep B protects
