Later it was found that there was a type of mosquito which acted as the carrier of this disease and passed it on to the rabbits. So while the rest of the world was trying to get rid of mosquitoes, Australia was encouraging this one. It effectively spread the disease all over the continent and drastically reduced the rabbit population. It later became apparent that rabbits were developing a degree of resistance to this disease, so that the rabbit population was unlikely to be completely exterminated. There were hopes, however, that the problem of the rabbit would become manageable. 后来又发现,有一种蚊子是传播这种疾病的媒介,能把此病传染给兔子。因此,世界上其他地方在设法消灭蚊子的时候,澳大利亚却在促使这种蚊子大量繁殖。蚊子把这种疾病扩散到整个澳洲大陆,效果甚佳,结果兔子的数目在为减少。后来,明显看出,兔子对这种疾病已产生了一定程度的免疫力,所以兔子不可能被完全消灭。但是,已有希望解决兔子所带来的问题。