Three months after the World Health Organization recommended singing "Happy Birthday" twice during hand-washing to fight the coronavirus, Fujitsu Ltd has developed an artificial intelligence monitor it says will ensure that health care, hotel and food industry workers scrub properly.

The AI, which can recognize complex hand movements and can even detect when people aren't using soap, was under development before the coronavirus outbreak for Japanese companies implementing stricter hygiene regulations, according to Fujitsu. It is based on crime surveillance technology that can detect suspicious body movements.

"Food industry officials and those involved in coronavirus-related business who have seen it are eager to use it, and we have had people inquiring about price," said Genta Suzuki, a senior researcher at the information technology company. Fujitsu, he added, had yet to formally decide on whether to market the AI technology.