The Survey ofCronobacterspp. (formerlyEnterbacter sakazakii) in Infant and Follow-up Powdered Formula in China in 2012

ObjectiveTo determineCronobacterspp.contamination in infant and follow-up powdered formula in China. MethodsAll of 2282 samples were collected from theretailmarkets in China from January 2012 to December 2012, and analyzed forCronobacter spp.by theChineseNationalFood Safety Standard. Characterization of the isolates was analyzed by pulsed-field gel electrophoresis (PFGE) withXbaI and SpeI restriction enzymes. ResultsCronobacterspp. strains were isolated from 25 samples, and the positive rates ininfant 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 ofCronobacterspp.to elucidate genetic diversity revealed only three pairs ofCronobacterspp.out of 25 having the same PFGE patterns. ConclusionThe current investigation indicated a lower positive rate ofCronobacterspp.in the powdered formula in China.This evidence suggested contamination originating from multiple different sources during the manufacturing process.