Multi-resistant refers to multi-drug resistant bacteria. Bacteria can cause a series of infections that result in clinical symptoms, and clinical treatment is mainly by applying antibiotics. If these bacteria are sensitive to these antibiotics, then the antibiotics will work, and if they are not, that is, resistance occurs, and there are difficulties in treatment in this case. Multi-drug resistant bacteria are those bacteria that are resistant to multiple antibiotics, usually to three or more classes of antibiotics, which is called multi-drug resistant bacteria, and in this case, more sensitive antibiotics need to be applied for treatment. Multi-drug resistant bacteria are more commonly seen in clinical practice as methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus, carbapenem-resistant Enterobacteriaceae, ultra-broad-spectrum β-lactamase-producing bacteria, and multi-drug-resistant Mycobacterium tuberculosis, Clostridium difficile, and multi-drug-resistant Pseudomonas aeruginosa.