You only get Hep B from infected needles and infected sex.
What are these hospital monsters doing that makes them know a one-day old must have this one shot, over all others?
They are the only practical way the baby gets infected.
Ghetto shots.
All the new rules and injections in medicine start with solving a problem for the lowest common denominator.
Foe example the newborn hepatitis shots were originally ghetto shots given because of the fact that ghetto kids had infrequent medical care growing up. Then they became standard of care for all newborns.
Chickenpox shots were originally called daycare shots for families who did not want to miss work. Then became another standard of care.