An important factor of resulting tobacco virusdisease is insect vectors.
媒介昆虫是烟草病毒病的重要成因因子。
2
Marburg virusdisease occurs very rarely and appears to be geographically confined to a small number of countries in the southern part of the African continent.
马尔堡出血热的发生极其罕见，并且似乎在地理上局限于非洲大陆南部少数国家。
3
Both cattle and chickens raised for meat are often fed the type of feed that transmits the virus that causes the disease.