As a physician, I am glad for the mobile health-monitoring applications that allow me to help my patients sleep better, exercise better and eat better. Yet I was a little offended when I learned of a new wristband monitor that prods doctors to wash their hands when they enter a patient's room.

The bracelet, conceived at the Blueprint Health technology incubator, was introduced by the startup company IntelligentM at the South by Southwest Interactive Festival last month. The device gives doctors and nurses a buzzing signal to wash; it emits further warnings if the cleansing isn't up to the standards set by the Centers for Disease Control and Prevention. Hospital-infection-control officers can get a buzz from the wristband, too: The technology tracks hand-washing compliance and can share reports with anyone who wants to know.

For those who value their autonomy, the latest practitioner-targeted technologies such as the IntelligentM wristband may be an irritant. But such measures are necessary, however demeaning they seem. In the average U.S. hospital, hand-washing compliance rates vary from just one-third of patient encounters to half at best. And hand hygiene is the single-largest contributor — and the most fixable — to the almost 2 million hospital-acquired infections each year that kill 100,000 people in the U.S.