Management of risk of microbial cross-contamination from uncooked frozen hamburgers by alcohol-based hand sanitizer.
This research was undertaken to determine the effectiveness of an alcohol-based hand sanitizer on hands contaminated with a nonpathogen surrogate for Escherichia coli O157:H7, where the source of the contamination was frozen hamburger patties. A nonpathogenic nalidixic acid-resistant food-grade strain of Enterobacter aerogenes was used to inoculate frozen hamburger patties composed of 76% lean beef and 24% fat. Thirty-two individuals participated to produce the data used in this study. Each participant handled nine patties at least three times, a sample for microbiological analysis was collected from the surface of one hand, the participant sanitized both hands, and a sample was collected from the other hand. Burger handling created perceptible and visible food debris on the hands of most participants. Computer simulations also were used to perform a variety of risk calculations. The average reduction in bacteria from the use of sanitizer on hands contaminated by frozen burgers containing E. aerogenes was 2.6 +/- 0.7 log CFU per hand. An experiment designed to simultaneously test the effect of sanitizer on E. aerogenes and E. coli O157:H7 also revealed no significant difference in sanitizer effectiveness against the two organisms. The results of the real-world risk estimation calculations (using the actual prevalence and concentration of E. coli O157:H7 in ground beef) predict that once in 1 million trials, a single pathogen cell will be transferred to a single lettuce piece. The effectiveness of this sanitizer intervention was similar to that for hand washing and glove use previously reported. The person-to-person microbial reduction variability from sanitizer use is similar to published data for glove use and was less variable than published data on hand washing effectiveness.
Schaffner
Donald W
DW
Food Risk Analysis Initiative, Rutgers University, 65 Dudley Road, New Brunswick, New Jersey 08901-8520, USA. schaffner@aesop.rutgers.edu
Schaffner
Kristin M
KM
D000438:Alcohols / Q000494:pharmacology*; D000818:Animals; D002417:Cattle; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004202:Disinfectants / Q000494:pharmacology*; D021902:Enterobacter aerogenes / Q000187:drug effects* / Q000254:growth & development; D004866:Equipment Contamination / Q000517:prevention & control*; D019453:Escherichia coli O157 / Q000187:drug effects / Q000254:growth & development; D017575:Gloves, Protective; D006235:Hand Disinfection; D006801:Humans; D008461:Meat Products / Q000382:microbiology*; D012308:Risk Management
D000438:Alcohols; D004202:Disinfectants