结论此类轻型急性呼吸道感染症传染性强，传播速度快，但病原体毒力较弱，症状较轻。

Conclusion Mild acute respiratory infection is highly infective and has a quick transmission, but the virulence of pathogens is relatively weak and hence symptoms are not serious.

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结论此类轻型急性呼吸道感染症传染性强，传播速度快，但病原体毒力较弱，症状较轻。

Conclusion Mild acute respiratory infection is highly infective and has a quick transmission, but the virulence of pathogens is relatively weak and hence symptoms are not serious.

youdao