Molecular Epidemiology ofBacillus cereusin a Pediatric Cancer Center

Abstract

Purpose: Bacillus cereus has been reported as the cause of nosocomial infections in cancer patients. In our pediatric cancer ward, a sudden rise in the number of patients with B. cereus bacteremia was observed in 2013 to 2014. This study was performed to investigate the molecular epidemiology of increased B. cereus bacteremia cases in our center. Methods: Pediatric cancer patients who developed B. cereus bacteremia were identified from January 2001 to June 2014. The B. cereus bacteremia in this study was defined as a case in which at least one B. cereus identified in blood cultures, regardless of true bacteremia. Available isolates were further tested by multilocus sequence typing (MLST) analysis. A retrospective chart review was performed. Results: Nineteen patients developed B. cereus bacteremia during the study period. However, in 2013, a sudden increase in the number of patients with B. cereus bacteremia was observed. In addition, three patients developed B. cereus bacteremia within 1 week in July and the other three patients within 1 week in October, respectively, during emergency room renovation. However, MLST analysis revealed different sequence types without consistent patterns. Before 2013, five tested isolates were ST18, ST26, ST177, and ST147-like type, and ST219-like type. Isolates from 2013 were ST18, ST73, ST90, ST427, ST784, ST34-like type, and ST130-like type. Conclusions: MLST analyses showed variable ST distribution of B. cereus isolates. Based on this study, there was no significant evidence suggesting a true outbreak caused by a single ST among patients who developed B. cereus bacteremia.

Control ofBacillus cereusspore germination and outgrowth in cooked rice during chilling by nonorganic and organic apple, orange, and potato peel powders

“…Bacterial toxin‐mediated outbreaks caused by B. cereus occur worldwide, as indicated by recent reports of such outbreaks in Australia (May, Polkinghorne, & Fearnley, ), Austria (Schmid et al, ), France (Glasset et al, ), the United Kingdom (Nicholls et al, ), and Germany (Kamga Wambo et al, ). These outbreaks might be associated with morbidity and mortality in humans consuming food contaminated with B. cereus (Kim et al, ; Oh, Chang, Choi, Ok, & Lee, ; Tschiedel et al, ).…”