In 2000, the World Health Organization (WHO) announced that China was already a polio-free country.

2000年，世界卫生组织（WHO）宣布中国已成为一个没有脊髓灰质炎的国家。

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The risk of importations into polio-free areas remains as long as polio exists anywhere in the world.

只要全世界任何地方存在脊髓灰质炎，输入到无脊髓灰质炎地区的危险则继续存在。

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Its main task is to monitor the polio-free status of the region.

其主要任务是监测该区域的无脊髓灰质炎状况。

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With increased political support and a detailed immunisation programme planned by the remaining endemic countries, there is a feeling of hope here that the world may soon be polio free.

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India was declared polio free in early 2012.

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Infected travellers had carried the virus to nearly 20 previously polio-free countries causing more than 1200 polio cases.

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