Objective To investigate a suspected outbreak of healthcare-associated infection （HAI） caused by carbapenem-resistant Klebsiella pneumonia （CRKP） in a secondary grade-A hospital， analyze the infection source and transmission route， and put forward corresponding preventive and control measures.

Methods Epidemiological investigation was conducted on 5 patients with CRKP infection in department of neurosurgery during December 23‒30， 2021. Specimens were collected with the environmental microbiology monitoring procedure. CRKP isolated from the environmental samples were analyzed by multilocus sequence typing （MLST） method. Comprehensive measures were taken to control the CRKP infection.

Results The 5 infected patients were located in 3 rooms， and all were diagnosed as HAI. The antimicrobial susceptibility testing results from the specimens of 3 CRKP infected patients were the same. Through environmental microbiology monitoring， CRKP strains were detected from the faucet handle and sink specimens in 3 rooms. The results of MLST analysis showed that the faucet handle and sink specimens in room 2 and 3 were ST11 type. The environmental specimen in room 1 was ST23 type. The suspected outbreak was effectively controlled after comprehensive interventions.

Conclusion HAI suspected outbreak might be caused by the environmental contamination from the pathogens of CRKP-infected patients as well as the contaminated hands of medical staff and accompanying family members. Strengthening the publicity， education and management of medical staff and accompanying staff， early identification of infection outbreaks， and timely comprehensive control measures are the keys to controlling multidrug-resistant nosocomial infection outbreaks.