Abstract: Cronobacter spp., which was formerly defined as Enterobacter sakazakii, is one of the main pathogenic bacteria that easily contaminates powdered infant formula (PIF) and can infect newborns and cause severe necrotizing enterocolitis, bacteremia and meningitis, with a high mortality rate of 40%–80%. This article reviews the commonly used methods for the phenotypic and molecular typing of Cronobacter spp. including biotyping, matrix-assisted laser desorption ionization time of flight mass spectrometry, serological typing, pulsed field gel electrophoresis, multilocus sequence typing, random amplification of polymorphic DNA, ribotyping, special genotyping and whole-genome typing with the aim of providing a better understanding of these methods, which will offer a basis for revealing the phenotypic characteristics and genetic diversity of Cronobacter spp..

Key words: Cronobacter spp., phenotyping, molecular typing, typing methods