Aim: Cronobacter sakazakii sequence types 1, 4, 8 and 12 are associated with outbreaks of neonatal meningitis and necrotizing enterocolitis infections. However clonality results in strains which are indistinguishable using conventional methods. This study investigated the use of clustered regularly interspaced short palindromic repeats (CRISPR)-cas loci profiling for epidemiological investigations.
Materials & methods: Seventy whole genomes of C. sakazakii strains from four clonal complexes which were widely distributed temporally, geographically and origin of source were profiled.
Results & conclusion: All strains encoded the same type I-E subtype CRISPR-cas system with a total of 12 different CRISPR spacer arrays. This study demonstrated the greater discriminatory power of CRISPR spacer array profiling compared with multilocus sequence typing, which will be of use in source attribution during Cronobacter outbreak investigations.
Keywords: CRISPR–cas; Cronobacter sakazakii; MLST; genotyping; sequence types.