translation.en: When they sample from animals, they collect the blood on the filter paper and this allows us to identify yet-unknown viruses from exactly the right animals -- the ones that are actually being hunted.
translation.zh: 当他们从动物身上提取样本时， 可以将提取的血液放到滤纸上 这就可以允许我们从特定的动物身上发现未知的病毒， 这些动物实际上是已经被捕获的。