HPV is transmitted through skin-to-skin contact during vaginal, anal, or oral sex. HPV is not passed through blood, semen, or other body fluids. Since it's not passed through blood you will be able to donate blood. A person can be infectious even if no symptoms are present, but the risk is probably greatest if contact is made with the warts themselves. The area most prone to infection are the thin mucous membranes of the vagina, vulva, penis, and scrotum.
Women who give birth can sometimes pass the warts to their child. There is little or no risk of catching HPV through towels or other inanimate objects.