Q: Can you get HIV from oral sex?
A: Yes, although few in number, there have been documented cases of HIV transmission through oral sex. The risk of transmitting HIV through oral is higher when infected pre-cum or semen comes into contact with the receiving partner's bleeding gums, open cuts, scratches or sores in the mouth. The CDC warns that "cells lining the mouth of the person performing oral sex may allow HIV to enter" the body. The same is true when rimming.
Many people that have oral also engage in rimming and anal, so the exact risk factors are hard to determine. But, the risk of getting HIV from oral alone is a lot less.
Use a latex barrier of a condom to reduce your risk of getting HIV just in case.