natural infestation的用法和樣例：
例句
- This is the first report of the presence of FMDV in bull semen due to natural infection in China.
這也是我國首次證實(shí)自然感染牛的精液被口蹄疫病毒污染。 - Because natural rotavirus infection was not associated with intussusception, they reasoned their vaccine would similarly not increase the risk of this complication.
由于自然感染輪狀病毒并不會(huì )造成腸套疊，因此他們認為新疫苗也不會(huì )增加這種并發(fā)癥的風(fēng)險。
