Virology Flashcards
recombination vs reassortment
recombination: exchanging homologous sections of DNA
reassortment: segmented DNA exchange segments, causing high frequency recombination
complementation
Think of Hepatitis D. Can’t infect with B because mising a protein
phenotypic mixing
genome of virus A coated with surface protein of B. occurs with coinfection. However progeny will be normal (Virus A coat with A DNA)
Live attenuated vaccines
smallpox yellowfever chickenpox sabin's polio MMR Influenza (intranasal)
Also BCG and salmonella typhi
immunity induced by live vs killed vaccines
live: cell mediated AND humoral, no booster
killed: ONLY humoral, need booster
Killed vaccines
Rabies influenza salk polio HAV bordetella
Recombinant vaccines
HBV, HPV
toxoid vaccines
diptheria and tetanus
Conjugate vaccine
HiB
All DNA viruses except _____ are dsDNA
parvoviridae
All DNA viruses are linear except
papilloma, polyoma, hepadnaviruses
DNA viruses
Herpes Hepad Adeno Parvo Papilloma Polyoma Pox (HHAPPPPy)
All DNA viruses are icosahedral except
pox
all DNA viruses replicate in the nucleus except
pox
which viruses are diploid?
ONLY retroviruses
RNA viruses repliate in
the cytoplasm. Except: influenza and retroviruses
Which viruses are infections by themselves (without cell machinery)
positive strand ssRNA and dsDNA (except pox and HBV)
DNA nonenveloped virus
papilloma Adeno parvovirus polyomavirus PAPP
RNA nonenveloped virus
CPR+H calcivirus picornavirus reovirus hepevirus
dsDNA and enveloped
herpes
hepadna
pox
dsDNA enveloped and linear
herpes
pox
dsDNA enveloped and circular
hepadna
dsDNA nonenveloped and circular
papillomavirus, polyomavirus
dsDNA nonenveloped and linear
adenovirus
ssDNA and linear (negative sense)
parvovirus
HHV-3
chickenpox
HHV-4
EBV
HHV-5
CMV
CMV causes
AIDs retinitis
HHV-6
roseola (reticular red rash in kids)
HHV-7
less common cause of roseola
HHV-8
kaposi’s sarcoma
viral conjunctivitis
adenovirus
virus causing hemorrhagic cystitis in kids
adenovirus
viruses in polyoma family
JC virus=PML
BK virus=transplant pts, targets kidney (BK=bad kidney)
Viruses in poxvirus family
small pox
vaccinia (cowpox=milkmaid blisters)
molluscum contagiosum
most common cause of sporadic encephalitis in US
HSV-1. Causes temporal rode encephalitis
VZV latent in
dorsal root or trigeminal ganglia
mononucleosis with a negative monospot test
CMV
virus latent in mononuclear cells
CMV
Roseola
high fevers for days (sz) then a diffuse macular rash
How do you get HHV-8?
sexual contact
Dx: HSV
PCR
–tzanck test: smear of opened skin vesicle
cowdry A inclusions
HSV
EBV infects what cells
B cells
atypical lymphocytes come from what cell
reactive cytotoxic T cells (not B cells!)
heterophile antibodies detected by agglutination of sheep RBC
positive monospot test
causes of mononucleosis NOT EBV
CMV
Toxoplasmosis
HHV-6
EBV causes what cancers
Burkitt’s lymphomas
nasopharyngela carcinoma
Hodgkins
Infections acquired during birth
Herpes
Chlamydia
Gonorrhea
GBS
enveloped RNA viruses
flavivirus
togavirus
retrovirus
coronavirus
orthomyxovirus
paramyxovirus
rhabdovirus
filovirus
arenavirus
bunyavirus
deltavirus
which enveloped RNA viruses are ss+ linear?
flavivirus
togavirus
retrovirus
coronavirus
which enveloped RNA viruses are ss- and linear segmented?
orthomyxovirus
Which enveloped RNA viruses are ss- and nonsegmented?
paramyxovirus
rhabdovirus
filovirus
enveloped RNA viruses ss- and circular
arenavirus
bunyavirus
deltavirus
which enveloped RNA virus ss-, circular, and segmented?
arenavirus
bunyavirus
enveloped RNA virus ss- circular, NON segmented
delta
nonenveloped RNA virus
reo
picorna
hepe
calci
nonenveloped RNA virus, linear ss+
picorna
hepe
calci
nonenveloped RNA ds Linear with 10-12 segments
reovirus
Which RNA viruses are icosahedral?
All the nonenveloped viruses (reo, picorna, hepe, calci) PLUS
flavivurs
togavirus
retrovirus
picornaviruses
polio echovirus-meningitis rhinovirus coxsackie-meningitis, mouth blisters, hand foot and mouth HAV PERCH on a peak (pico)
flaviviruses
HCV yellow fever dengue st louis encephalopathy west nile
toga viruses
rubella
Eastern equine
western equine
paramyxoviruses
parainfluenza-croup
RSV-bronchiolitis in babies
Measles/mumps
filovirus
Ebola
arenavirus
LCMV: lymphocytic choriomeningitis virus
Lassa fever encephalitis
bunyavirus
Hantavirus–hemorrhagic fever, pneumonia
Crimean-Congo Hemorrhagic Fever
Sandfly/Rift Valley Fever
California encephalitis
negative sense RNA viruses
Always bring polymerase or fail replication
- arenavirus
- bunyavirus
- paramyxovirus
- orthomyxovirus
- filovirus
- rhabdovirus
Segmented viruses
ALL RNA -orthomyxovirus bunyavirus arenavirus reovirus
pahtophys rhinovirus
Binds to ICAM-1 to get to epithelial cells. Acid labile, so destroyed by stomach acid
sx: yellow fever
flavivirus with monkey reservoir
-fever
BLACK VOMIT
jaundice
rotavirus presentation
segmented dsRNA
diarrhea in kids causing loss of Na and K with villous destruction
tx: rotavirus?
vaccination
hemagglutinin
orthomyxovirus component=viral entry
neuraminidase
promotes progeny virion release
risky complication of influenza?
bacterial superinfection.
what type of flu vaccine do you use in kids?
Live vaccine–nasal.
truncal rash that starts at head and moves down with fever, lymphadenopathy, arthralgias
rubella virus
F surface fusion protein causing respiratory epithelial cells to fuse and form multinucleated cells.
paramyxoviruses (RSV and parainfluenza)
prophylaxis for RSV in premature infants?
palivizumab (monoclonal antibody against F protein)
koplike spots and descending rash including hands and feet
measles
3 C’s of measles
cough
coryza
conjunctivitis
complications years later with measles
subacute sclerosing panencephalopathy
parotitis, orchitis, aseptic meningitis
mumps. worry about sterility in pts infected AFTER puberty
negri body
rhabies
where do you find negri bodies
purkinje cells of the cerebellum
bullet shaped virus
rabies
transmission rabies
bat, raccoon, skunk bites
incubation of HAV
weeks
classification HAV
RNA picornavirus
classification HBV
DNA hepadnavirus
classification HCV
RNA flavivirus
classification HDV
RNA delta virus
classification HEV
RNA hepevirus
inclubation HBV
months
incubation HCV
LONG-years?
would you rather be superinfected or coinfected with HDV?
coinfected. superinfection has a worse prognosis
incubation with HDV superinfection
short. if HDV coinfection, long incubation (matches that of HBV)
how do you get HDV/HBV
IV or sex, or maternal fetal
how does HBV vs HCV cause HCC?
HBV–activates oncogenes
HCV–causes cirrhosis which causes HCC
which hepatitis viruses are naked?
HAV and HEV. These do not have an envelope and therefore are NOT destroyed by the gut
describe the replication of Hep B
- virus enters cell
- dsDNA repaired in the nucleus
- transcribed to RNA
- RT of RNA–>DNA
- packaged into DNA
best test to detect active hep A
antiHAV IgM
Anti-HAV IgG
indicates prior infection or vaccination to HAV
hbSaG
INDICATES CURRENT HEPATITIS b INFECTION
Anti-HBc
antibody to core of HBV.
igM=acute or recent infection
IgG=prior exposure or chronic infection
Which serologic hep B marker is positive during the window period?
Anti-HBc
Anti-HBe and HBeAg tell you
transmissability. Battle between Anti-HBe and HBe antigen indicating how much the virus is replicating
Most people clear HBV and are fine. who is less likely to clear the diseaes?
intrapartum HBV infection. these kids have a 90% progression rate to chronic disease
What is the window period
Time between the end of HBsAg and start of Anti-HBs around 6 months after exposure where all serologic markers are negative
What order to serology markers peak in Hep B?
SECES
HBsAg
HBeAg
Anti-HBc
Anti-HBe
Anti-HBs
Acute HBV serology
HBsAg
HBeAg
anti-HBc IgM
window period
Anti-HBe
Anti-HBc IgM
chronic HBV (high infectivity)
HBs
HBeAg (would have anti-HBe if low infectivity)
Anti-HGc IgG
Recovery HBV
Anti-HBc IgG
Anti-HBe
Anti-HBs
HIV attachment to host cell
gp120
HIV fushion and entry to host cell
gp41
gag p24
capsid protein
pol
RT
aspartate protease
integrase
env
gp120 and 41
Dx of HIV
ELISA
western blot to follow up and rule in
AIDS diagnosis
CD4 < 200 or with AIDS defining condition
OR
CD4/CD8 ratio < 1.5
which HIV genes are needed for replication?
tat and rev
HIV disease if CD <100
systemic histoplasma: fever, cough, tongue ulcer, hepatosplenomegaly
toxoplasma: abscesses in brain causing ring enhancing lesions
esophageal candida
HIV illness if CD < 400
oral thrush
HIV illness if CD < 200
cryptosporidium: chronic watery diarrhea
JC virus reactivation; PML=progressive focal neuro deficit
PCP pneumonia
HIV illness if CD < 50
MAC
CMV=cotton wool spots and esophagitis/pneumonia
cryptococcus meningitis
How do you distinguish bacillary angiomatosis (bartonella) from kaposi’s sarcoma (HHV-8?)
biopsy
- kaposi’s: lymphocytic inflammation
- bartonella: neutrophilic inflammation
HIV cancers
hairy leukoplakia non-hodgkin's lymphoma squamous cell carcinoma of anus primary CNS lymphoma --many are associated with EBV
Causes of pneumonia in HIV +
CMV
aspergillus
PCP
MAC
gerstmann straussler sheinker syndrome
inherited prion disease
CJD is sporadic
diarrhea from seafood
vibrio parahemolyticus and vulnificus
diarrhea: meat/mayonaise/custard
staph aureus
diarrhea: undercooked beef/meat
EHEC
reheated meat dishes
clostridium perfringens
which bugs mimics appendicitis
yersinia enterocolitica
salmonella
campylobacter
causes of bloody diarrhea
campylobacter salmonella shigella EHEC/EIEC yersinia (think daycare, pseudoappendicitis) amoeba
C diff and C perfringens diarrhea
C diff: bloody or nonbloody
C perf: gas gangrene
neonatal pneumonia
GBS
E coli
Child pneumonia
RSV Mycoplasma chlamycia ( under 3) C pneumonia (school age) strep pneumo
pneumonia in adults
Mycoplasma
C pneumonia
S pneumonia
40-65 yo adult pneumonia
H flu
S pneumo
anaerobes
viruses
Elderly pneumonia
S pneumo Influenza Anaerobes H flu gram - rods
hospital and immunocompromised pneumonia
staph or enterics
alcoholic pneumonia
klebsiella, staph, strep pneumo
postviral pneumonia
staph
H flu
S pneumo
child meningitis
strep pneumo
N meningitidis
HiB
enteroviruses
Adult meningitis
S pneumo
n meningitidis
HSV
enterovirus
Elderly meningitis
S pneumo
listeria
e coli
empirical tx meningitis
ceftriaxone/vanco
Add ampicillin if suspect listeria (old or young)
sexually active osteomyelitis
neisseria
diabetic/IV drug osteomyelitis
pseudomonas, serratia
opening pressure in viral meningitis
normal/slight increase
CSF tap in fungal/TB meningitis
increase protein, decreased sugars
lymphocytes
increased opening pressure
CSF tap in viral meningitis
normal opening pressure
lympcytes
normal protein (maybe slight elevation)
normal sugar
difference btw leukocyte esterase test and positive nitrite
nitrite test tells you bacteria are gram negative
urine urease test comes back positive
proteus or klebsiella
2nd/3rd leading cause of UTI
staph saprophyticus
klebsiella
swarming motility and struvite stones UTI
proteus
classic causes of reactive arthritis
chlamydia
enterics (salmonella, shigella, campylobacter, yersinia)
TORCHES infections
toxoplasma rubella CMV HIV HSV2 Syphilis
In a neonate:
chorioretinitis
hydrocephalus
intracranial calcifications
toxoplasma
In a neonate: PDA Cataracts Deafness blueberry muffin rash
rubella
In a neonate:
HEARING LOSS, SEIZURES, BLUEBERRY muffin rash
CMV
In a neonate:
recurrent infections and chronic diarrhea
HIV
In a neonate:
encephalitis, herpetic lesions
HSV2
In a neonate:
hydrops fetalis
syphilis or Parvovirus B19
In a neonate:
saddle nose
saddle teath
CNVIII deafness
syphilis
Infection of lymphatics and small painless genital ulcers with rectal strictures
lymphogranuloma venereum
vaginitis, strawberry mucosa, and motile wet prep
trichomoniasis
aortitis
tertiary syphilis
creamy purulent discharge and urethritis/cervicitis/epididymitis
gonorrhea
chancroid, a painFUL genital ulcer with inguinal adenopathy
haemophilus decreyi. School of fish appearance.
Most common STD in the US
Chlamydia
Infection of the liver capsule and violin string adhesions of parietal peritoneum to liver. In sexually active person
What is Fitz Hugh Curtis syndrome
donovan bodies and a painless ulcer
klebsiella granulomatis
Rubella vs measles
rubella: Rash starts at head and moves down with postauricular lymphadenopathy
measles: Rash starts at head and moves down. Preceded by cough, coryza, conjunctivitis, and koplic spots
largest DNA virus
pox virus
All RNA viruses except ____ are ss RNA
Reovirus
Reoviruses
Rotavirus
Coltivirus: colorado tick fever
Calcivirus
norovirus
Retroviruses
HTLV
HIV
SARS
coronavirus
Rash in measles vs rubella
Measles rash INCLUDES the hands and feet
Rubella rash is limited to the TRUNK