Vaccinating children against rotavirus, for example, can protect them from a pathogen that is responsible for 37% of all diarrhea deaths in children under five, thus saving 450,000 lives every year. Similarly, vaccines exist to protect against pneumococcal disease, which accounts for a half-million pneumonia-related deaths annually.
免疫也是一种高效方式。比如，接种轮状病毒疫苗的儿童可以抵抗一种导致5岁以下儿童37%的痢疾死亡的病原体，从而每年能可以拯救450000条生命。类似地还有肺炎球菌疫苗，肺炎球菌疾病每年造成一半的肺炎相关疾病死亡。