Thank you for your inquiry. From what we gather from the question, you were asking about the possibility of HIV transmission from walking over a piece of broken glass, which may have been previously contaminated with blood. From the information provided, this scenario is determined to be Negligible Risk (there are no evidence or no documented cases of transmission).
HIV (contained in a body fluid such as blood) is extremely sensitive to the outer environment. Exposure to oxygen in an environment outside of the body causes HIV to undergo a rapid reduction in concentration (1). From the CDC, HIV that may be contained in a fluid (e.g. the blood that may have been on the glass that you stepped on), has a rapid (within several hours) reduction in concentration of 90-99% (1).
Although you stepped on the glass very shortly after the other individual, as soon as the blood left their body, it was exposed to air, which would render it inactive as mentioned above. You said that the glass had pricked you as well; however, according to the HIV Transmission Equation (see the image below), HIV transmission requires direct access to the bloodstream, and it is unlikely that the prick of glass on your foot was large/deep enough to allow this.
Therefore, although there is a theoretical possibility of HIV transmission from this scenario, it is quite unlikely, due to exposure of the blood to the air as well as the cut on your foot being too small to allow direct access of any HIV particles to your bloodstream. However, if both of you had large open wounds, this would entail a higher risk assessment.
Recommendation: Refer to a healthcare professional for more personalized answers. If you are worried that you may have been exposed to HIV, it is always responsible to receive testing if possible.
AIDS Vancouver Online/Helpline, Shirley
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(1) HIV Environmental Exposure