Hospital-acquired infections are mainly studied in the context of

Patients, health care workers, medical equipment and the environment. The main objects of hospital infection research include patients, health care workers, medical equipment and the environment, etc. Patients are one of the main objects of hospital infection research, health care workers in the medical operation often contact with the patient's bodily fluids, secretions and a variety of medical equipment, which is prone to become a vector of germs, medical equipment such as ventilators, catheters, etc., if not properly used or cleaned, it is prone to become a breeding ground for germs.