The swab test, which involves taking a mucus sample from the nasal cavity, can distinguish between swine flu (H1N1), A and B strains of the virus.

这个棉签试验，需要从鼻腔采取一些粘液样本，能够区分出猪流感(H1N1)中的A和B病毒株，伦敦南部的圣乔治医院现在就是用流感Xpert试验。

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Now 10 to 30 days before surgery, all patients must have pre-admission testing including a nasal swab and must attend a class about preventing infection.

WSJ: Steps for Surgical Patients to Fight Infection