Common acute disease, caused by a virus of
the herpes group and transmitted by airborne
droplets. Chickenpox chiefly attacks children
under ten. The incubation period is two to
three weeks. One attack normally gives
immunity for life. The temperature rises and
spots (later inflamed blisters) develop on
the torso, then on the face and limbs. The
sufferer recovers within a week, but remains
infectious until the last scab disappears.