With regard to blood stains - a dear friend/female client who thought she was post menopausal was in for a massage - requested craniosacral pelvic diaphragm release to relieve unmitigating pelvic pain - WHAMMO!!! Instant menstrual period after 11 months w/o one!!! Fixed her up with pads I keep on hand for client emergencies, a pair of my underpants, and laundered the fleece pad, the sheets, the heating pad sheet and all is well... no harm no foul.
Diarrhea happens, quite literally. If it happens during a session, the client can escape to my bathroom, clean up, and return, while I strip the table, disinfect, and set the table again. Wash the sheets, if they come out spot free, they get used again, if not, they become household rags, no big deal.
Ejaculate happens too and not always for sexual reasons. Individuals who are skin starved/touch deprived may have ejaculatory episodes just from receiving touch to their skin while being massaged. It has absolutely nothing to do with sexual gratification or deviant behavior. It is particularly possible with elderly clients who have had little physical contact with others after the death of a spouse/significant other. It is also possible in cloistered populations of the religious and others who practice segregation from the general population for purposes of contemplation, etc. Yes, it can be a biohazard, but, before you judge it as such, be sure you consider, quite literally, the individual who was the source. A middle-aged male client inadvertently deposited an ejaculate sample just recently. He has been celibate for nearly 2 years since the break-up of his marriage. It was near the anniversary of the divorce, he had been thinking about how much he missed her touch, and, oops, deposit made. Rather than add to his embarrasment, I merely covered his pelvis with a small towel over the sheet, and continued the massage. Afterward, he thanked me for not "yelling at me and making me feel like I had done something wrong." Did I throw out the sheets? No. No need to do such a thing. Just gathered them up and washed them like any other set of sheets and all is well.
Do I like it when such things occur? It's not something I would say I'm really keen on, but, if it happens, it's part of the naturalness of life and you just deal with it and move on. No biggie.