Prevalence of Bacillus cereus in powdered infant and powdered follow-up formula in China

Outbreaks and sporadic cases of foodborne disease caused by Bacillus cereus have been reported in China, including cases involving infants and children. However, the prevalence of B. cereus contamination in foods is not clearly known. In China, no legal microbiological criteria for B. cereus in powdered infant formula (PIF) and powdered follow-up formula (PFUF) currently exists. The purpose of the study was to investigate the prevalence of Bacillus cereus in PIF and PFUF sold in China and to provide data that could be used for risk assessment and management to ensure the safety of these kinds of products. As part of the national surveillance program, 6656 samples of PIF and PFUF were collected quarterly from urban and rural markets in 31 provincial-level administrative units in China in 2014. The results show that 7.53% of the samples were contaminated with B. cereus ≥10 CFU/g and 1.11% of the samples were contaminated above 100 CFU/g. There were no statistical differences of B. cereus contamination levels between PIF and PFUF or between samples taken from retail, wholesale and online outlets. The prevalence of B. cereus-positive samples differed between sampling regions and production regions. The occurrence of B. cereus >10 CFU/g of samples produced in summer and autumn, which were 8.80% and 9.18%, respectively, were higher than those in spring and winter, which were 6.67% and 6.32%, respectively. The study indicated a need to conduct further research on B. cereus contamination in powdered formula products in China before microbiological criteria are developed.