ABSTRACT
This study aimed to evaluate the Cronobacter spp. strains isolated on the American continent and characterized using multi-locus sequence typing (MLST) available in the PubMLST database and current literature. From 465 Cronobacter spp. strains, the majority (n = 267, 57.4%) was from North America, mainly from USA (n = 234) and 198 (42.6%) were from South America, mainly from Brazil (n = 196). A total of 232 (49.9%) were isolated from foods, 102 (21.9%) from environmental, 87 (18.7%) from clinical, 27 (5.8%) from PIF, one from water (0.2%) and 16 (3.5%) from unknown sources. A total of five species were represented: Cronobacter sakazakii (374, 80.4%), Cronobacter malonaticus (41, 8.8%), Cronobacter dublinensis (29, 6.2%), Cronobacter turicensis (16, 3.5%) and Cronobacter muytjensii (5, 1.1%). The strains with complete MLST profile (n = 345) were assigned to 98 STs, a ratio of 3.5 strain by ST found and the calculated Simpson`s index was 0.93. The strains showed a high diversity and after eBURST analysis, 30 STs (n = 189) formed 12 single and/or double-locus variant clonal complexes (CC). A total of 38 STs (38.7%) were associated with clinical cases of infection, including well established C. sakazakii CC 1, 4, 8 and 83; C. malonaticus ST60, 307, 394 and 440; and C. sakazakii ST 12 and 494.
Subject(s)
Cronobacter/classification , Cronobacter/isolation & purification , Enterobacteriaceae Infections/epidemiology , Foodborne Diseases/microbiology , Infant Formula/microbiology , Cronobacter/genetics , Cronobacter sakazakii/genetics , Cronobacter sakazakii/isolation & purification , Databases, Factual , Enterobacteriaceae Infections/microbiology , Genetic Variation/genetics , Humans , Infant , Infant, Newborn , Multilocus Sequence Typing , Peptide Elongation Factor G/genetics , United States/epidemiologyABSTRACT
Cronobacter sakazakii is an opportunistic foodborne pathogen associated with necrotizing enterocolitis, bacteremia, and meningitis in infants. A comparative proteomic study of C. sakazakii ATCC BAA-894 (CS WT) and a fliF::Tn5 mutant was performed, including the ability of both strains to adhere to and invade N1E-115 cells. To achieve this goal, a nonmotile C. sakazakii⬠ATCC BAA-894 fliF::Tn5 (CS fliF::Tn5) strain was generated using an EZ-Tn5
Subject(s)
Cronobacter sakazakii , Neuroblastoma , Animals , Cronobacter sakazakii/genetics , Mice , ProteomicsABSTRACT
We describe a case of infection with Cronobacter sakazakii sequence type 494 causing bacteremia and meningitis in a hospitalized late premature infant in Brazil. We conducted microbiological analyses on samples of powdered infant formula from the same batch as formula ingested by the infant but could not identify the source of contamination.
Subject(s)
Cronobacter sakazakii/classification , Cronobacter sakazakii/genetics , Enterobacteriaceae Infections/diagnosis , Enterobacteriaceae Infections/microbiology , Meningitis, Bacterial/diagnosis , Meningitis, Bacterial/microbiology , Bacteremia , Brain/pathology , Brazil , Enterobacteriaceae Infections/transmission , Food Contamination , Food Microbiology , Humans , Infant , Infant, Newborn , Magnetic Resonance Imaging , Meningitis, Bacterial/transmission , Multilocus Sequence TypingABSTRACT
Several Cronobacter species are opportunistic pathogens that cause infections in humans. The aim of this study was to detect Cronobacter spp. from 90 samples of retail foods in Brazil, and characterize the strains by phenotypic tests, molecular assays and antibiotic susceptibility. Three isolation methodologies were evaluated using different selective enrichments and the isolates were identified using Vitek 2.0, PCRs protocols, fusA allele sequencing and multilocus sequence typing (MLST). Thirty-eight samples (42.2%) contained Cronobacter spp., and the highest percentage was found in flours (66.7%, 20/30), followed by spices and herbs (36.7%, 11/30), and cereal mixes for children (23.3%, 7/30). The 45 isolates included four species: C. sakazakii (n = 37), C. malonaticus (n = 3), C. dublinensis (n = 3), and C. muytjensii (n = 2); that presented 20 different fusA alleles. MLST analysis revealed 32 sequence types (STs), 13 of which were newly identified. All strains were sensitive to all antibiotics (n = 10) tested. The combination of CSB/v enrichment with DFI plating was considered the most efficient for Cronobacter spp. isolation. This study revealed the presence of Cronobacter spp. in foods commercialized in Brazil and the isolates showed a high diversity after MLST analysis and included two strains of the C. sakazakii ST4 neonatal meningitic pathovar.
Subject(s)
Anti-Bacterial Agents/pharmacology , Cronobacter/genetics , Cronobacter/isolation & purification , Food Microbiology , Bacterial Typing Techniques , Bacteriological Techniques/methods , Brazil , Cronobacter/classification , Cronobacter/drug effects , Cronobacter sakazakii/genetics , Cronobacter sakazakii/isolation & purification , Drug Resistance, Bacterial , Flour/microbiology , Multilocus Sequence Typing , Peptide Elongation Factor G/genetics , Phenotype , Polymerase Chain Reaction , Spices/microbiologyABSTRACT
Cronobacter (formerly known as Enterobacter sakazakii) is a genus comprising seven species regarded as opportunistic pathogens that can be found in a wide variety of environments and foods, including powdered infant formula (PIF). Cronobacter sakazakii, the major species of this genus, has been epidemiologically linked to cases of bacteremia, meningitis in neonates, and necrotizing enterocolitis, and contaminated PIF has been identified as an important source of infection. Robust and reproducible subtyping methods are required to aid in the detection and investigation, of foodborne outbreaks. In this study, a pulsed-field gel electrophoresis (PFGE) protocol was developed and validated for subtyping Cronobacter species. It was derived from an existing modified PulseNet protocol, wherein XbaI and SpeI were the primary and secondary restriction enzymes used, generating an average of 14.7 and 20.3 bands, respectively. The PFGE method developed was both reproducible and discriminatory for subtyping Cronobacter species.