The human deaths from H5N1 have so far occurred as a result of direct infection from birds - except in two outbreaks where rare human-to-human transmission appears to have occurred.
至今所有死于禽流感的患者除了两例罕见人与人之间传播的病例外，均为直接从鸟类感染。
2
Studies should identify local mosquito species that play a role in WNV transmission, including those that might serve as a “bridge” from birdstohuman beings.
研究应确定当地传播西尼罗河病毒的蚊子种类，包括可能“桥接”鸟类和人类的蚊子。
3
Widespread prevalence of the virus in birds increases the chance of transmission from bird tohuman.