Question

why cant most stis be transmitted through casual contact with people or contaminated objects?

Explanation:

Most STIs (sexually - transmitted infections) are caused by pathogens that require specific conditions to survive and be transmitted. These pathogens are often fragile and cannot live outside the human body for long periods or cannot penetrate the intact skin of casual contact. They typically need direct contact with mucous membranes (such as in sexual activity) or blood - to - blood contact for transmission.

Answer:

Most STI - causing pathogens are fragile outside the body and require specific contact (like with mucous membranes or blood - to - blood) rather than casual contact for transmission.