Koalas are extremely prone to chlamydia infections.

考拉极易感染衣原体。

The next stage is then tested in what we call on efficacy trial to see if it actually reduces the rate of chlamydia infection.

该疫苗很大程度上仍处于早期阶段。下一阶段将我们将在药效试验中进行测试，看看它是否真的降低了衣原体感染的几率。