Hepatitis B Virus
aka HBV, HepB
Baltimore VII (dsDNA) retrovirus
Screen pregnant women
Ix for mum
HBsAg
HBcAb
HbsAb
If sAg, cAb, sAb all neg > vaccinate
sAg neg, cAb pos = previous infection and immune
sAg neg, cAb neg, sAb pos = immunised
sAg pos = infected
(HBeAg
HBeAb
LFTs)
Exposure during pregnancy
- HBsAb >10IU/ml = no action, vaccinate as usual
- HBsAb <10IU/ml then
Vaccination
0,2,4,6 mo (and a 4th booster at 12mo if <2kg or <32/40 at birth)
Baltimore VII (dsDNA) retrovirus
Screen pregnant women
Ix for mum
HBsAg
HBcAb
HbsAb
If sAg, cAb, sAb all neg > vaccinate
sAg neg, cAb pos = previous infection and immune
sAg neg, cAb neg, sAb pos = immunised
sAg pos = infected
- Mum need assessment by adult ID and hepatocellular carcinoma surveillance
- Check mums HAV IgG, if non-immune vaccinate
- check HBV DNA: viral load >10^7IU/ml then mum needs lamivudine, tenofovir or telbivudine from 30/40 until 1-3m postpartum at least (monitor ALT monthly for 3 months for maternal flare)
- can have NVD but minimise invasive procedures
- baby need both HBIg 100IU IM, and HepB vaccine at birth (within 12 hours) AT SEPARATE SITES
- Ok to breastfeed
- Further HepB vaccines as usual
- HepB serology at 9mo, if HBsAg pos refer to ID, if sAg neg but sAb <10IU/ml needs further vaccination
(HBeAg
HBeAb
LFTs)
Exposure during pregnancy
- HBsAb >10IU/ml = no action, vaccinate as usual
- HBsAb <10IU/ml then
- HepB Vaccine and HBIg AT SEPARATE SITES within 72 hours
- repeat vaccine at 1 and 6months
- check HBsAg at 3 months, if positive and still pregnant > as per above algorithm for sAg pos
Vaccination
0,2,4,6 mo (and a 4th booster at 12mo if <2kg or <32/40 at birth)