感染性的英文：
infectivity

Acute infective conjunctivitis
急性感染性结膜炎

An infected or diseased patch of skin.
感染性的皮肤一块感染或患病的皮肤

The optimism of those Saturday afternoons was contagious
那些星期六下午出现的乐观精神具有感染性。

vehicle of infection
传染媒介物

The infection swelled his hand.
感染使他的手肿了起来。

To infect with corruption or decay.
使腐败传染腐化或腐朽

Cholera is a bacterial infection.
霍乱是一种细菌感染。

Coughs and sneezes spread infections.
咳嗽和打喷嚏会传播传染病。