Primary prevention of acute respiratory infection among United States Air Force recruits through the use of antimicrobial handwipes: a randomized clinical trial
This double-blinded randomized clinical trial was performed to determine the efficacy of antimicrobial handwipes in reducing acute upper respiratory infections among United States Air Force Basic Military Trainees and in changing the prevalence of Group A Beta-hemolytic Streptococcus pyogenes (GABS) positive throat cultures.The study was conducted in two phases. During Phase I, forty recruits were block randomized into four groups of ten subjects each. Two groups used antimicrobial handwipes containing parachlorometaxylenol (0.5%) and alcohol (40%); with one group additionally using hand soap containing triclosan. A third group used placebo handwipes containing water and lemon juice, and a fourth group continued normal handwashing practices. Bacterial hand counts were determined.In Phase II, fifty groups (each consisting of approximately 53 recruits) were block randomized to use either the aforementioned antimicrobial or placebo handwipes during the six-week basic military training period. From medical records and questionnaires, data on sick-call visits were collected. Using pharyngeal specimens collected at the beginning and end of training, changes in GABS positive throat culture prevalence were recorded.Findings from Phase I of the study, showed antimicrobial handwipes, when compared to either placebo handwipes or normal hygiene practices, produced a highly significant 71.4% reduction in hand colony counts (p-value $>$.001). The addition of triclosan hand soap did not significantly change hand colony counts among those using antimicrobial handwipes (p-value = 0.38).During Phase II, antimicrobial handwipes lowered the incidence of initial sick-call visits for acute upper respiratory infection by 32.7 percent (p-value = 0.02) and visits for sore throat by 40 percent (p-value = 0.01). GABS positive throat culture prevalence tripled (0.8% to 3.0%) during the training period for flights assigned to placebo handwipes, while the prevalence remained unchanged (1.2%) for those assigned to antimicrobial handwipes.These data suggest antimicrobial handwipes may prove an effective method of reducing direct contact transmission of pathogens in high risk groups.
- Epidemiology