When do hais generally occur?

It is an infection that usually happens to a person that's been under somebody's care ( medical ).

Explanation:

They generally occur within 24-48 hours. A person can develop it almost anywhere: from emergency room, through hospitals, to surgical centers. HAIs are usually caused by bacteria, like fungi, some viruses, or numerous different pathogens. They happen when a place isn't very clean and sterile. In order to prevent them, medical stuff should use: gloves, face shield, goggles, etc.