title: Quantitative microbial risk assessment of antibacterial hand hygiene products on risk of shigellosis.
abstract: There are conflicting reports on whether antibacterial hand hygiene products are more effective than nonantibacterial products in reducing bacteria on hands and preventing disease. This research used new laboratory data, together with simulation techniques, to compare the ability of nonantibacterial and antibacterial products to reduce shigellosis risk. One hundred sixtythree subjects were used to compare five different hand treatments: two nonantibacterial products and three antibacterial products, i.e., 0.46% triclosan, 4% chlorhexidine gluconate, or 62% ethyl alcohol. Hands were inoculated with 5.5 to 6 log CFU Shigella; the simulated food handlers then washed their hands with one of the five products before handling melon balls. Each simulation scenario represented an event in which 100 people would be exposed to Shigella from melon balls that had been handled by food workers with Shigella on their hands. Analysis of experimental data showed that the two nonantibacterial treatments produced about a 2-log reduction on hands. The three antibacterial treatments showed log reductions greater than 3 but less than 4 on hands. All three antibacterial treatments resulted in statistically significantly lower concentration on the melon balls relative to the nonantibacterial treatments. A simulation that assumed 1 million Shigella bacteria on the hands and the use of a nonantibacterial treatment predicted that 50 to 60 cases of shigellosis would result (of 100 exposed). Each of the antibacterial treatments was predicted to result in an appreciable number of simulations for which the number of illness cases would be 0, with the most common number of illness cases being 5 (of 100 exposed). These effects maintained statistical significance from 10(6) Shigella per hand down to as low as 100 Shigella per hand, with some evidence to support lower levels. This quantitative microbial risk assessment shows that antibacterial hand treatments can significantly reduce Shigella risk.
authors.affiliation: Department of Food Science, Rutgers University, 65 Dudley Road, New Brunswick, New Jersey 08901, USA. schaffner@aesop.rutgers.edu.
authors.forename: Donald W
authors.initials: DW
authors.lastname: Schaffner
authors.affiliation: James P. Bowman & Associates LLC, 6409 Roth Ridge Drive, Loveland, Ohio 45140, USA.
authors.forename: James P
authors.initials: JP
authors.lastname: Bowman
authors.affiliation: Avon Products, Inc., One Avon Place, Suffern, New York 10901, USA.
authors.forename: Donald J
authors.initials: DJ
authors.lastname: English
authors.affiliation: Gefmey Consulting LLC, 4808 North 24th Street, Phoenix, Arizona 85016, USA.
authors.forename: George E
authors.initials: GE
authors.lastname: Fischler
authors.affiliation: Henkel Consumer Goods Inc., 19001 North Scottsdale Road, Scottsdale, Arizona 85255, USA.
authors.forename: Janice L
authors.initials: JL
authors.lastname: Fuls
authors.affiliation: Personal Care Products Council, 1101 17th Street N.W., Suite 300, Washington, D.C. 20036-4702, USA.
authors.forename: John F
authors.initials: JF
authors.lastname: Krowka
authors.affiliation: American Cleaning Institute, 1331 L Street N.W., Suite 650, Washington, D.C. 20005, USA.
authors.forename: Francis H
authors.initials: FH
authors.lastname: Kruszewski
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015169:Colony Count, Microbial; D019662:Cucurbitaceae / Q000382:microbiology; D004305:Dose-Response Relationship, Drug; D004405:Dysentery, Bacillary / Q000635:transmission; D005511:Food Handling / Q000379:methods*; D005522:Food Services / Q000592:standards; D006225:Hand / Q000382:microbiology; D063373:Hand Hygiene; D064548:Hand Sanitizers / Q000494:pharmacology*; D006801:Humans; D018570:Risk Assessment
chemical_list: D000900:Anti-Bacterial Agents; D064548:Hand Sanitizers