Ultrasound abdomen and Sonomammography.

Hello Doctor, I have a question regarding the safety of ultrasound procedures. I need an abdomen, pelvis, and breast (sonomammography) ultrasound, but I have some small pimples and minor scratches on my skin. I am concerned about the possibility of infection if there is any blood or contamination on the probe from previous patients. I read that probes are disinfected after every use, but as part of my previous experience they are not cleaning simpling keeping aside using on every patient , **am not speaking about transvaginal scan . but I would like to know: 1. What is the actual risk of HIV or other infections in this situation? 2. Can I use my own disposable probe sheet to further reduce any risk? 3. Will using a probe sheet affect the quality of the ultrasound images? I want to make sure the procedure is completely safe. Could you please guide me on the best precautions I should take before and during the scan? Please respond ..