PHHP 17 - An Uncommon Culprit, Bacillus Cereus, as a Foodborne Bloodstream Infection (BSI)

Background: Bacillus cereus, a foodborne illness, occurs within 6-15 hours after consuming contaminated food items. Associated symptoms include nausea, vomiting and diarrhea. An investigation was launched following an inquiry from an outside hospital (OSH) regarding an increase in B. cereus cases amongst their leukemic population potentially linked to a protein powder. Whole genome sequencing was performed on all of our B. cereus cases but no epidemiologic link was identified between any of the cases. However, a potential food source was not considered when attempting to identify the source of infection.

All cases were actively receiving treatment for various cancer diagnoses during the time of their B. cereus infection, diarrhea being a common side effect of chemotherapy, making a foodborne illness an uncommon culprit given their symptoms at baseline.

Methods: Chart review was conducted on four admitted cases during the time of their infection to determine if they consumed the protein powder. Around the same timeframe there was a voluntary Food and Drug Administration recall for potential microbial contamination associated with a large foodservice distributor, which included food items served at our facility. A supplemental review was conducted simultaneously to determine if any of the recalled items were also consumed.

Results: As a result, it was determined that no cases consumed the protein supplement linked to the OSH. However, one case consumed one of the recalled food items on three separate times.

Conclusions: It is still unclear as to what caused the spike in cases and what has ultimately caused the overall increase in B. cereus cases we have seen thus far in 2022. However, this investigation highlights the importance of considering contaminated food items as the potential source of infection when investigating B. cereus BSIs in the hospital setting.