Most of them live in poor and remote communities that still lack access to the basic vaccines that are universally available in better-off countries. This is one of the reasons why a child born in a high-income country is 18 times less likely than a child born in a low-income country to die before reaching the age of five.
但是，可悲的是，每20秒钟就有一名儿童死于肺炎等可以通过疫苗预防的疾病。这些死亡患儿大多生活在贫困而偏远的社区，得不到富裕国家人人可得的基本疫苗。这就是生于高收入国家的儿童五岁前夭折几率比生于低收入国家儿童低18倍的原因之一。