My skin goes red and blotchy.

我的皮肤变红而且起了斑点。

《柯林斯英汉双解大词典》

A red blotchy rash.

红色斑疹。

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This is followed in 3 to 7 days by a dusty red, blotchy rash that begins on the face and then extends over the rest of the body and lasts for 4 to 6 days.

初期主要症状为发烧，咳嗽，流鼻涕及红眼，此后3至7天面部出现灰红色泡疹，并逐渐蔓延至身上其它部位，这一症状将持续4到6天。

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The symptoms of bacterial meningitis are a very high temperature, stiff neck, and a blotchy red or purple rash which does not fade when the side of a glass is pressed against it.

BBC: Vaccine hope for deadly brain bug

It often has the appearance of a blotchy, lacy, red and brown rash, which may be itchy or burning at times.

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