Prevalence and Genetic Diversity of Cronobacter Species Isolated From Four Infant Formula Production Factories in China

Abstract

The aim of this study was to investigate the prevalence and genotypic characteristics of Cronobacter isolated from powdered infant formula (PIF) manufacturing facilities and to identify a potential source of contamination. A total of 42 Cronobacter isolates (5%) were detected in 835 environmental samples collected during the surveillance study. These isolates included C . sakazakii ( n = 37), C . malonaticus ( n = 3), and C. turicensis ( n = 2). The isolates were divided into 14 sequence types (STs) by multi-locus sequence typing (MLST) and 21 pulsotypes (PTs) using pulsed-field gel electrophoresis (PFGE). The dominant C. sakazakii sequence types were ST3 ( n = 12) and ST21 ( n = 10), followed by ST136 ( n = 6). The major PTs were PT22 ( n = 12) and PT17 ( n = 4) based on 100% similarity. Strains isolated from samples collected at the same production facility showed closer phylogenetic relation than those collected from distinct facilities. The result of extensive traceback sampling showed that PIF residues (PIF dust in production areas), fluid beds, drying areas, floors, and soil samples collected adjacent to the production facilities were the primary positive areas for Cronobacter . The present study outlines an effective approach to determine prevalence and genetic diversity of Cronobacter isolates associated with contamination of PIF.

Genotypic and antimicrobial resistance characterizations of Cronobacter sakazakii isolated from powdered milk infant formula: A comparison between domestic and imported products

“…detection and identification of C. sakazakii in food samples as well as PMIF (Mashoufi et al, 2019). Recently; because of the employing strong surveillance and checking quality control of the manufactured and imported PMIF products, prevalence of C. sakazakii in PMIF has significantly been decreased (Lu & Matthews, 2019).…”

“…We identified C. sakazakii in PMIF samples by real‐time PCR melting curve assay in our study; however, there are many researchers suggest SYBR green melting curve real‐time PCR with species‐specific primers a precise, sensitive and specific method for detection and identification of C. sakazakii in food samples as well as PMIF (Mashoufi et al., 2019). Recently; because of the employing strong surveillance and checking quality control of the manufactured and imported PMIF products, prevalence of C. sakazakii in PMIF has significantly been decreased (Lu & Matthews, 2019). However, different range of prevalence from 2.8% to 12.3% contamination rates of C. sakazakii was reported by researchers about PMIF samples (Henry, 2018).…”

Advances in our understanding and distribution of the Cronobacter genus in China

“…A number of in‐depth studies of the distribution of Cronobacter in PIF manufacturing plants have been published and are highlighted in Table 2. The organism has been recovered from the ingredients as well as environmental samples (including roofs) from the spray‐drying, fluidized‐bed, and packing areas (Fei et al., 2015; Lu et al., 2019; Pei et al., 2019). Caprine (goat) milk powder is also used as an infant formula.…”

“…Given the desiccation survival of Cronobacter , the dissemination of Cronobacter via air‐borne dust particles is very important to control in PIF production facilities. Dust particles in the air of a manufacturing plant can be a vector of Cronobacter dispersal, and could contaminate the final product during bagging and the final packing (Fang et al., 2015; Fei et al., 2015; Lu et al., 2019; Pei et al., 2019). Wu et al.…”

Natural Compounds With Antibacterial Activity Against Cronobacter spp. in Powdered Infant Formula: A Review

“…Microbiological assessments of milk powder and PIF manufacturing environments and processes have shown that Cronobacter spp. may derive from extrinsic sources, notably dry ingredients, or intrinsically contaminated sites where specific strains may persist over long periods of time (29)(30)(31)(32)(33). Moreover, most strains examined to date have shown higher resistance to potentially lethal osmotic and dessication stresses than other human pathogen belonging to the family Enterobacteriaceae.…”