The study shows that the initial infection source of the disease is the disease spot on the branches. In the growing season branches, leaves and fruits can infect one another.

研究发现，病害的初侵染源来自枝干病斑，生长季节枝、叶、果互相交叉传染。

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Initial investigations into the source of his infection suggest a number of sudden chicken deaths occurred around the case's house a week before onset.

感染源初步调查显示，病人出现症状的一周前，其住所的周边地带曾突然出现过大量鸡只死亡。

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