Microbiology 5s - Viral hepatitis Flashcards
Incubation period of Hep A
2-6 weeks
which hep virus is DNA?
Hep B
is HAV a notifiable disease?
Yes
diagnostic test for HAV
HAV IgM
differentiating between vaccinated HAV and infected
Infected have HAV IgM and raised ALT
Vaccinated only HAV IgG raised
What is the definition of chronic hep and what % with HBV go on to have chronic disease?
hepatitis (HbSin Ag) >6 months
10%
HBV incubation period
2-6 months
Transmission of HAV/HBV/HCV/HEV?
HAV = FO route HBV = Blood products, sexually, vertically HCV = BLOOD products (Rarely sexual) HEV = FO
what % of <5 year olds with HBV develop chronicity?
90%
In HBV, What serological marker suggests active infection?
Anti-HbC IgM +VE
which marker is a marker of immunity in HBV?
Anti-HbS IgG if vaccinated and NO core or envelope antibodies
drugs used in treatment of HBV
Peginteferon alpha
NRTIs which inhibit viral replication e.g. tenofovir, lamivudine, emtricitabine
Baby HbSAg +ve, eAg -ve at birth
Vaccine at birth
baby HbsAg +Ve eAg +Ve at birth
Vaccine at birth + HBIG <48 HRS
incubation period HCV
6-8 weeks
what % of HCV infection –> chronic?
60%
how do you screen for acute HCV infection
You cannot check the anti-HCV as they tend to develop after HCV infection so need to do HCV RNA/viral load
new treatment for HCV
DAAs = direct acting antivirals, 12 week treatment course
WHAT KIND of virus is hep D?
Delta virus - ssRNA, smallest virus known to infect man
co-infections vs superinfection of Hep B + Hep D
Co-infectino can get quite a nasty acute hepatitis but low risk of chronicity
if you first get hep B and then superimposed hep D, get chronic infection and high risk of liver disease
HEV - describe the diff genotypes?
1 + 2 = human
3 + 4 = swine
HEV - high prevalence in which country?
Time course?
India + North Africa
acute i.e. 2-8 weeks
To whom is HEV particularly dangerous
Pregnant women –> high mortality, especially genotype 1
Mx of HEV?
sUPPORTIVE unless chronic in which case you give ribacvarin
