感染流行性感冒

catch flu

再次感染

be reinfected

身体不好容易感染各种疾病。

If one's body is weak then one gets all sorts of diseases.

病人因感染发高烧。

The patient was infected and is now running a high fever.

人感染禽流感病毒

humans infected by the avian flu virus

我被他的愉快心情感染了。

I was infected by his happiness.