The study was reported on by various outlets this week, such as the Independent and the Guardian. This is the most recent of a number of studies on the issue, and jet dryer manufacturers can give plenty of reasons to take its findings with a grain of salt.
In the study, the researchers asked participants to dip their gloved hands into a solution of a harmless virus called MS2. After giving their hands a quick shake, the participants tried one of the three drying methods. The researchers then collected samples from the air and from surfaces (petri dishes placed before the experiment) at different distances from where the drying procedure occurred. The jet air dryer was far and away the worst offender, spreading more viruses farther.