Objective To understand the current status of Cronobacter sakazakii (Cronobacter spp.) infection and its molecular epidemiological characteristics among patients with diarrhea, so as to provide evidence for the prevention and control of diarrhea disease caused by infection with Cronobacter spp. in Changping District, Beijing.

Methods 760 stool samples were collected from the diarrhea patients in a sentinel hospital in 2019, for the detection of Cronobacter spp., Salmonella, diarrheogenic Escherichia coli (DEC), and Vibrio Parahaemolyticus. Meanwhile, drug sensitivity experiment and pulsed-field gel electrophoresis (PFGE) typing analysis were conducted on the Cronobacter spp. strains isolated.

Results A total of 20 Cronobacter spp. strains (2.63%) were isolated, with a lower detection rate than that of Salmonella and Vibrio Parahaemolyticus (χ²=9.052, P=0.011). However, there were no statistically significant differences between the detection rates in Cronobacter spp. and DEC (χ²=1.076, P=0.300). Seasonal characterization analysis showed that Cronobacter spp. could be detected in spring (1.00%), summer (4.17%), autumn (3.00%) and winter (1.67%), and the differences were statistically significant (χ²=662.700, P<0.001). The PFGE analysis showed that 20 PFGE banding patterns were found in 20 Cronobacter spp. strains, with a similarity coefficient ranging from 56.30% to 90.09% and a diverse PFGE banding pattern. The drug sensitivity experiment results showed that 18 (90.00%) strains were resistant to cefazolin, and 2 (10.00%) strains were intermediate. While, as for cefoxitin, 2 (10.00%) strains were resistant to it, and 5 (25.00%) strains were intermediate. All the 20 strains were 100.00% sensitive to the other 11 antibiotics.

Conclusion In the study, Cronobacter spp. is detected in all seasons through the year, with a high resistance rate to cefazolin, no multi-drug resistant bacteria appeared, and diverse PFGE banding patterns.