The stepped-up drive to secure a polio-free world continues to intensify in those countries where the disease threatens most.
The stepped-up drive to secure a polio-free world continues to intensify in those countries where the disease threatens most.
以无小儿痲痹世界为目标的运动，继续在此疾病最具威胁性的国家紧锣密鼓地展开。