Hepatitis Flashcards
what is viremia?
virus in the blood
how is viremia diagnosed (2)?
- IgG and IgM
- PCR
when is IgM seen?
early in infectious cycle
6 weeks - 3 months
when is IgG seen?
after IgM
lasts several years
hepatitis viruses have a predisposition for ___________
hepatocytes
how is Hep A transmitted?
fecal-oral
why are ice cubes dangerous for Hep A?
freezing does not inactivate Hep A
ice = very stable environment
how can you get rid of Hep A in food?
boil for > 1 min to inactivate
what geographical locations have a high prevalence of Hep A?
Africa
Asia
Northern Canada
what kinds of areas have a high distribution of Hep A?
areas that lack clean water and god health care
what are some symptoms of Hep A?
jaundice
fatigue
abdominal pain
loss of appetite
nausea
diarrhea
fever
who gets jaundice with Hep A?
more common in adults
less common in children
when is active hep A spread?
shed 2 weeks pre and post jaundice
what is the incubation period for Hep A?
2-7 weeks after exposure
long incubation = high spread
when does recovery of Hep A occur?
within 2 months
what is the length of immunity after being infected with Hep A?
lifelong immunity
how does Hep A enter the blood?
from intestine and/or oropharynx
what cell type does Hep A target? what is the result of this?
targets Kupffer cells in liver
virus replicates without causing lysis
virus released in bile and stool
what are the 3 routes of Hep A transmission?
- food/water
- close personal contact
- blood exposure
how do you diagnose acute Hep A?
detection of HAV-IgM in serum
how do you diagnose past infection (immunity) of Hep A?
detection of HAV-IgG by EIA
how is Hep A prevented?
- vaccination
- pre exposure prophylaxis
- post exposure prophylaxis
are there antivirals for Hep A?
no
how long does Hep A seroconversion take?
4 weeks
what age group does better when diagnosed with Hep C?
those who acquire infection at a younger age
what are the symptoms of Hep C?
mostly asymptomatic
fatigue
loss of appetite
nausea
weight loss
abdominal pain
jaundice
how is Hep C transmitted?
blood and body fluids
IV drug use
sexual
occupational (ie. needle stick injuries)
how is Hep C diagnosed?
anti-HCV serologic screening
detected within 8 weeks of infection onset
how is Hep C diagnosed for CLINICAL MANAGEMENT?
quantitative nucleic acid amplification assays for HCV RNA
is there a vaccine for Hep C?
no
how is Hep C prevented?
- screen blood, tissue and organs
- modify high risk behaviours
- blood and bodily fluid precautions
where is Hep B most prevalent?
Asia
Africa
America
prevalence of Hep B increases as people become _________
sexually active
how does age affect risk of developing chronic illness with Hep B?
earlier the disease is acquired, the greater chance of developing chronic infection
if you BEAT Hep B you have ___________
lifelong immunity
what are the (3) modes of transmission for Hep B?
- sexual
- parenteral
- perinatal
what fluids have high concentrations of Hep B?
blood
wound exudates
what fluids have MODERATE concentrations of Hep B?
semen
vaginal fluid
saliva
fluids have LOW concentrations of Hep B?
urine
feces
sweat
what are the top 3 infection risks from needle stick injuries?
- Hep B
- Hep C
- HIV
how is Hep B diagnosed?
antigens (from virus) and antibodies (from host response)
core protein
surface proteins
e-antigen
HBsAg
HBV surface antigen
indicates INFECTION
HBsAB
antibodies against HBsAg
indicates IMMUNITY
HBcAB-IgM
early core antibody
appears after HBsAg
indicates ACUTE INFECTION
HBcAB-IgG
past core antibody
indicates CHRONIC INFECTION (or past resolved)
HBeAg
envelope antigen
indicates ACTIVE REPLICATION
(easily spread)
HBeAB
antibodies against HBeAg
indicates NOT ACTIVELY REPLICATING
(low transmissibility)
how is Hep B prevented?
- recombinant vaccine
- immunglobulin
- antivirals
what does the Hep B vaccine consist of?
HBsAg
