她于2009年6月5日开始出现症状。

Her symptoms started on 5 June 2009.

youdao

1月11日开始出现症状，最初为发热。

Onset of symptoms started on 11 January with fever.

youdao

感染之后15 - 20天开始出现症状。

It takes 15 to 20 days to start getting symptoms after being infected. [1] You may not get any symptoms at all.

youdao

And then you would recover for a while, that initial phase of the illness would disappear, your fever might go down, you might appear to be normal.

接着你会暂时恢复,在开始阶段出现的症状会消失,你的体温会降下来,看起来似乎比较健康

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