Often the way a host finds out they have a parasite is when the parasite has been feeding on them for so long that the host becomes ill and then has to address the problem.

经常的，一个宿主发现自己有寄生虫的方法，是当寄生虫已经寄居了如此长时间致使让自己病倒时，才会不得不处理这个问题。