Despite intensive investigations extending over several years, research has failed to find an animalreservoir of the virus or determine where it hides in nature between outbreaks.
尽管延续几年的强化调查，但是研究未能发现该病毒的动物储主或确定两次暴发之间它隐藏在自然界的何处。
2
Neisseria meningitidis only infects humans; there is no animalreservoir.
脑膜炎奈瑟菌仅感染人类，不存在动物宿主。
3
After the worldwide SARS epidemic in 2002-2003, sporadic cases continued to arise in southern China, possibly because of human contact with the animalreservoir.