Oral herpes (usually HSV-1) has been detected in both the saliva and blood of patients with active oral infections. It is the most prevalent form of HSV, and infection is most likely to occur during preschool years. Oral herpes is easily spread by direct exposure to saliva or even from droplets in breath. Skin contact with infected areas is sufficient to spread it. Transmission most often occurs through close personal contact, such as kissing. In addition, because HSV-1 can be passed in saliva, people should also avoid sharing toothbrushes or eating utensils with an infected person. It can also be passed with sharing chap stick. Though I have never heard of it from a Hookah, or another smoking device, it is definitely possible if a person with a an exposed sore was to use it and pass it immediately. I do not know how long the virus stays active after it is exposed to air.
Yes you can but it's rare. Herpes Simplex 1 is very common 50% off all adults over the age of 24 have it. Conditions have to be right for passing, such as the infected person has to be close to an outbreak and the possible recipient has to have a slightly weakened immune system, such as a cold or allergies. Most hookah smokers know this and now who has it. Like I have HS-1 and my wife doesn't married for over 3 years and she has never got it. My Father has it and my mother doesn't. He got it in high school and with over 30 years of marriage and she hasn't got it yet.
Best thing to do is keep mouth tips at home.
Most lounges not about to be closed by the health department hand them out. I personally keep several hundred of them at home and take them with me to lounges and other friends house when we smoke.