B族链球菌(GBS)是革兰氏阳性溶血性链球菌属中的一组,在日本1975年前后方受到重视,新生儿受该菌感染后易导致败血症、脑脊髓膜炎等重症感染,未成熟儿的病情尤重,死亡率亦高。目前认为本病的感染途径是经产道的垂直感染,日本妇女阴道中带菌者约为10～20%,但带菌者不一定均发生垂直感染。依其发病时间可分为早发及迟发二型,早发型 Streptococcus group B (GBS) is a group of Gram-positive hemolytic streptococcus, which was paid attention to in Japan before and after 1975. Neonatal infection with this bacterium can easily lead to severe infections such as sepsis and meningitis. The condition of immature children is particularly serious, and the mortality rate is also high. At present, the infection is thought to be caused by the vertical infection of the birth canal. The incidence of vaginitis in Japanese women is about 10-20%. However, vertical infection may not always occur in carriers. According to the onset time can be divided into two types of early onset and late onset, early hair type