Yes, definitely. In fact, I may petition the idea that tea can cure anything. :-) In all seriousness though, tea contains beneficial antioxidants that help sustain and reinforce the immune system, thus shortening the duration of illness. Also, any kind of warm beverage may act as an expectorant for a cough. If you sweeten your tea with honey, that is an added benefit, because before there was cough syrup, people used honey, and it works very well.
Thank you sir, may I have another?!