Hair in my food - illness?

So today I found a strand of hair in a packet of orted nuts. It was gross. Not to mention that I realized it after I put it in my mouth...ewww. My question is what would happen if the hair belonged to someone that had an illness of some sort - like hepatitis or aids or something? I know that when someone has hepatitis the doctor advises you to not kiss that person or touch their sweat so what about a hair strand from such a person? I don't know whos hair it was or where it came from.