A University of Michigan School of Public Health study led by Dr. Allison Aiello [13] is evaluating the effectiveness of handwashing and facemasks in preventing influenza from spreading. The study, called M-FLU, conducted a randomized cluster intervention trial among students living in dorm housing. The students were randomly separated into two intervention groups, one wearing masks and practicing hand hygiene, one just wearing masks, and also in a control group. The study was carried out over the 2006-2007 influenza season, which was a mild season. The study found that facemasks and hand hygiene were correlated with a 35-51% reduction in influenza-like illness [13] .