在古代，痘疮是很难被治愈的。
一天一个女孩儿来看他，女孩儿手上有个牛痘疮。
One day a girl came to see him who had a cowpox sore on her hand.
2009年，由他们手指上采集的痘疮样品被单独送到疾病防控中心进行分析。
Samples from their fingers were sent independently to the Centers for Disease Control and Prevention in 2009 for analysis.
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