Workers providing essential services in Japan during the coronavirus crisis are not only facing a higher risk of infection than most but are also often being treated poorly by those they are helping.

Supermarket employees, delivery truck drivers and postal workers among others have remained at their posts while people in many other occupations have been asked to stay home or work from home under an all-Japan state of emergency.

But the National Supermarket Association of Japan said many workers at its member stores have reported that they are "worn out due to customer complaints" about product shortages and "feel upset at the inhumane treatment" they have suffered.