一个简单的词放在句子里就不知道了的状况

When Europeans reached the Americas in 1492, the two populations exposed each other to completely novel diseases.The American peoples got by far the worse end of the exchange, through diseases such as measles, influenza and, especially, smallpox.

got by far the worse end of the exchange请问这句话的意思是？

by far 可以翻译成--到现在为止，动词get用的是过去式got所以可以翻译成--到那时为止，by far在句中是个介词短语作状语，修饰形容词比较级the worse,end在这里可以翻译成--端，譬如像 upper end--高档，相对于the worse end来讲另一端就是bad end,由于在上文中提到了the two populations所以下文才有了两端的相互比较，of the exchange可以与上文中的the two populations exposed each other to completely novel diseases相互呼应，基于两个不同种族或群体公开的互相接触并使他们历程了相对于双方而言的新型疾病才有了下文的the worse end of the exchange,exchange 在这里可以理解为疾病互相传染中的一种交互状况。所以我的翻译是--到那时为止美国人反而成为了受害者。