Two Cases of Multi-antibiotic Resistant Cronobacter spp. Infections of Infants in China / 生物医学与环境科学（英文）

Infections by Cronobacter spp. are hazardous to infants since they can lead to neonatal meningitis, bacteremia, and necrotizing enterocolitis. Cronobacter spp. are frequently resistant to β-lactam derivatives, macrolides, and aminoglycosides. In addition, multi-resistant strains have also been detected. In China, the isolation rate of Cronobacter spp. from commercial powdered infant formula (PIF) or follow-up formula (FUF) is relatively high. Nevertheless, clinical cases of Cronobacter infection have been ignored to date. Here we describe two cases of Cronobacter infection detected at the Wuhan Women and Children Medical Care Center Hospital (Wuhan City, China). We provide the genomic analysis of the isolates and the antibiotic-resistance profiles of the two strains. The Cronobacter strains identified in this study were not susceptible to third-generation cephalosporins, aminoglycoside, and/or trimethoprim-sulfamethoxazole. Whole genome sequencing revealed various genes known to encode antibiotic resistance. Future studies are needed to determine whether the genes predicted in this study are functional. As with Enterobacter spp., the antibiotic resistance of Cronobacter is a serious issue that requires more attention.

Study on identification of Cronobacter spp.species in 11 areas in China / 中华流行病学杂志

Objective To compare different methods on the identification of Cronobacter (C.) spp.species and to choose an optimum one.Methods Biochemical test,16S rRNA and fusA sequencing methods were carried out.Results When using the biochemical test,105 strains showed six different conditions but C.turicensis and C.universalis could not be effectively identified.Under the 16S rRNA sequencing analysis,all the strains were divided into 5 groups but C.sakazakii and C.malonaticus were tangled.Finally,all the strains were identified into 58 C.sakazakii,30 C.malonaticus,11 C.dublinensis,5 C.turicensis,1 C.muytjensii,under the fusA sequencing analysis.Conclusion Currently,fusA sequencing analysis seemed an effective method for identifying the species of Cronobacter.Since fusA sequencing analysis method was less intuitive,another method for rapid testing should be developed.

Study on identification of Cronobacter spp.species in 11 areas in China / 中华流行病学杂志

Objective To compare different methods on the identification of Cronobacter (C.) spp.species and to choose an optimum one.Methods Biochemical test,16S rRNA and fusA sequencing methods were carried out.Results When using the biochemical test,105 strains showed six different conditions but C.turicensis and C.universalis could not be effectively identified.Under the 16S rRNA sequencing analysis,all the strains were divided into 5 groups but C.sakazakii and C.malonaticus were tangled.Finally,all the strains were identified into 58 C.sakazakii,30 C.malonaticus,11 C.dublinensis,5 C.turicensis,1 C.muytjensii,under the fusA sequencing analysis.Conclusion Currently,fusA sequencing analysis seemed an effective method for identifying the species of Cronobacter.Since fusA sequencing analysis method was less intuitive,another method for rapid testing should be developed.

The Survey of Cronobacter spp. (formerly Enterbacter sakazakii) in Infant and Follow-up Powdered Formula in China in 2012 / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To determine Cronobacter spp. contamination in infant and follow-up powdered formula in China.</p><p><b>METHODS</b>All of 2282 samples were collected from the retail markets in China from January 2012 to December 2012, and analyzed for Cronobacter spp. by the Chinese National Food Safety Standard. Characterization of the isolates was analyzed by pulsed-field gel electrophoresis (PFGE) with XbaI and SpeI restriction enzymes.</p><p><b>RESULTS</b>Cronobacter spp. strains were isolated from 25 samples, and the positive rates in infant powdered formulas and follow-up powdered formulas were 0.90% (10/1011) and 1.18% (15/1271), respectively. Analysis of variable data regarding different purchasing store formats, seasonality, and production locations as well as comparison of infant versus follow-up formulas did not reveal statistically significant factors. During the sampling period, one of six surveillance zones did exhibit a statistically significant trend towards higher positive rate. PFGE characterization of Cronobacter spp. to elucidate genetic diversity revealed only three pairs of Cronobacter spp. out of 25 having the same PFGE patterns.</p><p><b>CONCLUSION</b>The current investigation indicated a lower positive rate of Cronobacter spp. in the powdered formula in China. This evidence suggested contamination originating from multiple different sources during the manufacturing process.</p>

Pesquisa de Cronobacter spp. em fórmulas infantis desidratadas / Screening the dehydrated powdered infant formulae for Cronobacter spp

Cronobacter spp. é uma bactéria oportunista associada a surtos de infecção em neonatos e criançasem virtude de consumo de fórmulas infantis desidratadas (FID). Neste contexto, o setor reguladortem criado normas específicas para o controle destes agentes patogênicos nas fórmulas infantis. Nesteestudo foi pesquisada a ocorrência de Cronobacter spp. em 60 amostras de FID comercializadas no Riode Janeiro, Brasil. Foram analisadas 30 amostras de fórmulas infantis para lactantes (0-6 meses) e 30 defórmulas infantis de seguimento para lactantes (> 6 meses) seguindo-se a metodologia de cultivo descritano Bacteriological Analytical Manual Online–FDA (2012). A identificação das colônias característicasfoi realizada com uso de kits ID32E, API20E e do sistema Vitek 2.0; e pela reação da polimerase emcadeia (PCR) com alvo no gene gluA. Nenhuma amostra apresentou contaminação por Cronobacterspp. Concluiu-se que a ocorrência de Cronobacter spp. em FID parece ser baixa, o que indica que osprodutores estão cumprindo o disposto nas normas brasileiras vigentes de forma a evitar a contaminaçãodos produtos por este micro-organismo...

Phenotypic profiles and detection of target genes by PCR in isolates from different sources and reference strains, identified as Cronobacter spp. (Enterobacter sakazakii)

Cronobacter, formerly known as Enterobacter sakazakii, is a novel genus of the Enterobacteriaceae family recognized as a cause of high number of fatal cases in neonates, after consuming infant formula. The conventional methods for detecting these organisms are time-consuming and lack sensitivity. The ISO/TS 22964:2006 is the most recently standardized methodology for detecting Cronobacter in powderedinfant formula. This study aimed at confirming the Brazilian isolates previously identified as E. sakazakiias Cronobacter spp. by biochemical assays, and also to compare characteristics of 37 Cronobacter andnon-Cronobacter isolates; and the miniaturized kits and the ISO/TS methodology were evaluated. A conventional PCR protocol targeting dna G was also developed and a previously described gluA targeting protocol was used. The majority of the Brazilian isolates were not confirmed as Cronobacter spp., and the selective enrichment step of ISO/TS methodology was inhibitory to some Cronobacter strains. The ID 32 Ewas the most reliable kit. The PCR protocol targeting gluA showed consistent results with ID 32E and the developed dnaG PCR protocol was 100% sensitive and specific. Thus, the PCR protocols targeting gluA and dnaG might be used to complement the Cronobacter spp. detection or identification after performing the conventional isolation and identification methods.

Primer aislamiento de Cronobacter spp (Enterobacter sakazakii) en fórmula láctea en polvo producida en Chile / First isolation of Cronobacter spp (Enterobacter sakazakii) in powdered baby formula in Chile

La familia Enterobacteriaceae contempla agentes comunes en las enfermedades transmitidas por los alimentos. De esta familia Cronobacter spp, es considerado un patógeno que afecta principalmente a recién nacidos, los que pueden adquirirla a través de fórmulas lácteas infantiles en polvo contaminadas. Objetivo: Pesquisar Cronobacter spp, en una fórmula láctea en polvo producida en Chile. Material y método: En julio de 2008, se obtuvieron 80 muestras desde una planta ubicada en la Región de Los Lagos. Para el aislamiento de Cronobacter spp, se utilizó el método descrito en la norma ISO/TS 22964. Las muestras fueron analizadas en el Laboratorio de Alimentos del Instituto de Medicina Preventiva Veterinaria de la Universidad Austral de Chile. Resultados: Del total de muestras analizadas, el 5 por ciento (4 / 80) fueron confirmadas como Cronobacter spp, constituyendo así el primer reporte de esta bacteria en Chile. Conclusión: Cronobacter spp, está presente en una fórmula láctea en polvo producida en Chile. Su presencia en este producto representa un riesgo que no es considerado en el actual Reglamento Sanitario de los Alimentos de nuestro país.

The family Enterobacteriaceae includes agents that are commonly transmitted through food. Within this family, Cronobacter spp, is considered to be a pathogen that primarily affects newborns, which can acquire it through contaminated powdered formula. Objective: Isolate Cronobacter spp, in a powdered milk formula produced in Chile. Material and method: In July of 2008, 80 samples were obtained from a factory in the Los Lagos Region. To isolate Cronobacter spp, the methods described in the ISO/TS 22964 specifications were used. The samples were analyzed at the Food Laboratory at the Institute of Preventative Veterinary Medicine and the Universidad Austral de Chile. Results: Of all analyzed samples, 5 percent (4/80) were contaminated with Cronobacter spp, which constitutes the first report of this bacterium in Chile. Conclusion: Cronobacter spp is present in powdered baby formula produced in Chile. It’s presence in this product represents a risk that is not considered in the current food safety standards in this country.

Ocorrência de Cronobacter spp. (Enterobacter sakazakii) em alimentos infantis adquiridos em um hospital público / Occurrence of Cronobacter spp. (Enterobacter sakazakii) in infant food purchased in a public hospital

Cronobater spp. (E. sakazakii) é considerada um micro-organismo oportunista que vem ganhando atenção de autoridades de Saúde Pública, pelo crescente número de surtos de infecção em recém–nascidos e lactentes. A bactéria está associada a casos raros, com alta taxa de mortalidade, podendo causar meningites, enterocolite necrosante e septicemia. Cronobacter spp. tem ampla disseminação, porém apenas as fórmulas lácteas infantis em pó foram, epidemiologicamente, associadas às doenças causadas por esse agente. No presente estudo foi avaliada a ocorrência de Cronobacter spp. em alimentos destinados às crianças de 0-36 meses de idade, adquiridos em lactário de um hospital público do município de São Paulo. Vinte e seis amostras de fórmulas reconstituídas e 24 produtos em pó foram analisados segundo a metodologia da ISO. Cronobacter spp. foi detectada em uma amostra (3,8 por cento) reconstituída de alimento infantil à base de farinha de milho e em quatro desse produto em pó (16,7 por cento). A bactéria não foi detectada nas fórmulas infantis destinadas às crianças de 0-6 meses, contudo sua presença em outros alimentos infantis pode contribuir para a contaminação do ambiente e dos utensílios dos lactários por meio da contaminação cruzada.