Hi Kim,
Some Australian guidelines are here: https://ranzcog.edu.au/RANZCOG_SITE/media/RANZCOG-MEDIA/Women's%20Health/Statement%20and%20guidelines/Clinical-Obstetrics/Management-of-Hepatitis-B-in-pregnancy-(C-Obs-50).pdf?ext=.pdf
In particular to answer your queries:
“All HBsAg-positive women should be tested for HBeAg anti-HBe, and HBV DNA level, to identify pregnancies at increased risk of post-exposure prophylaxis failure. … Women with a high viral load in the third trimester (>200,000IU/ml, equivalent to 6 log copies/ml) should be offered antiviral therapy during late pregnancy to reduce viral load prior to delivery, and the risk of mother-to child transmission of Hepatitis B”
and “In addition to routine vaccination, infants born to HBsAg-positive mothers should receive passive immunisation with HBIG…Anti-HBs antibody and HBsAg levels should be measured in infants born to mothers with chronic hepatitis B infection 3 to 12 months after completing the primary vaccine course.”
So, to clarify, I again think I may have been misleading in my prior post (I will go back and add some corrections) - the standard is to measure HBeAg and HBV DNA, giving antivirals if you have a high viral load. People who are HBeAg-negative generally have a lower viral load as you say.
Sorry to cause any shock!
TT