While countries shut borders to travellers from southern Africa fearing the spread of a new strain of the virus that causes Covid-19, vaccine makers were racing to get their hands on it to test if their products will still work.
由于担心引发新冠感染的一种新型病毒的传播，各国对来自南部非洲的旅行者关闭了边境，而疫苗制造商正竞相获取这种病毒的样本，以测试他们的产品是否仍然有效。
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