Placental transfer of ige antibodies against Haemophilus influenzae type bcapsular polysaccharide in Brazilian term and preterm newborns

Placental transfer of antibodies to polysaccharide antigens is still a cont roversial subject. The incidence of invasive Haemophilus influenzae type b (Hib) infections is high in countries where the vaccine has not been includ ed in routine immunization schedules. In the present work, we proposed to e valuate the natural immune response to nib capsular polysaccharide in term and preterm Brazilian newborns and their respective mothers. Although the m eans, medians, and ranges of antibody titres in paired maternal and cord se ra from preterm neonates were similar, the maternal levels were slightly hi gher than the cord levels and a poor correlation between these levels was v erified. Term neonates showed similar antibody levels to those of their res pective mothers and a very significant correlation between these levels was observed.