Hospital surfaces are a reservoir of many pathogens, such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), and Clostridium difficile. The contaminated surfaces are frequently touched by the hands of patients or healthcare workers, which facilitate the spreading of pathogens in the clinical environment. Such hospital care-associated infections can harm the health of the hospital population and even lead to death. Although daily sterilization can reduce iatrogenic infections, some resistant bacteria, such as MRSA and VRE, can survive on dry surfaces for days to weeks, and Clostridium difficile can survive for months. In addition, pathogens may develop resistance to residual antibiotic drugs and disinfectants in the environment. Given that ICU patients are usually seriously ill with high doses of antibiotics used to prevent infection, it is necessary to study the distribution pattern of pathogens in the ICU environment and identify the key factors affecting their dynamics.