"maternal antibody protection" . "passive immune protection" . "therapeutic vaccine" . "Maternally-derived antibodies" . "Passive immunity" . "Passive immunity#Naturally acquired passive immunity" . "Passively acquired maternal antibodies" . "passive immunisation" . "induce similar levels of immunity" . "serum" . "passive immunity" . "maternally transmitted antibodies" . . "horse serum" . "Passive immunity" . "maternal immunization" . "passive immunization" . . "Passive immunity#Naturally acquired" . . "Passive_immunity#Artificially_acquired" . "maternal antibodies" . . "\\\"passive\\\" immunity" . "Passive_immunity#Artificially_acquired_passive_immunity" . "passive immunotherapy" . "maternal antibody" .