Hartsfield's a port of entry in the North America and it's within a two-hour flight of 80 percent of the U.S. population.

哈茨菲尔德是北美的一个入境港，80%的美国人乘坐两小时的航班即可抵达。

The way a typical virus travels is it has a port of entry, it replicates locally, it makes it into the bloodstream, it circulates widely, it finds its target tissues, and then it replicates there.

典型病毒的传播方式是，它有一个进入口，在本地复制，进入血液，广泛循环，找到目标组织，然后在那里复制。