I am afraid for my friend and me. One day we were in a bus and he touched some blood with his elbow and he touched it with his hands. Then, we spent the day fixing my bike, I am not sure if he ate any food or if we shared any food or something with our hands so that worries me if we did, and I am afraid if he had a wound on his elbow because we ride bikes and fall very often. So was there a risk? Thank you in advance