Worldwide, most infections occur from mother-to-child, from child-to-child (especially in household settings), and from reuse of unsterilized needles and syringes.

• 就全世界而言，大多数感染发生在母亲与婴儿、儿童与儿童(尤其在家庭环境中)之间以及再次使用未经消毒的针头和注射器。