VOA慢速英语:部分剂量黄热病疫苗在紧急情况下有效

antibody – n. a substance produced by the body to fight disease

dose – n. the amount of a medicine, drug, or vitamin that is taken at one time

encouraging – adj. causing a hopeful feeling

outbreak – n. a sudden increase in the number of cases of a disease

cohort – n. a friend or someone you know

clinical – adj. related to a place where medical treatment is provided

scale – n. the size of something, especially when compared to something else