How can hiv/aids be transmitted from one person to another without having any form or sexual contact and why

Can someone give me one specific health problem (within unhealthy eating) and explain it. !

In which way does nicotine cause addiction? by stimulating the brain’s pleasure center by increasing blood-sugar levels by decreasing dopamine levels by reducing depression and anxiety

If scientists are trying to use what they know about hsv to devise a means of protecting other people from being infected, which of the following would have the best chance of lowering the number of new cases of infection? a) vaccinate of all persons with preexisting cases of hsvb) interfere with new viral replication in preexisting cases of hsvc) treat hsv lesions to shorten the breakoutd) educate people about avoiding sources of infection