Mercury vapor in the air can be very toxic. Families have been poisoned from mercury spills in the home which have not been properly cleaned up.
Children are at highest risk.
The small amount of mercury in fever thermometers, thermostats and fluorescent bulbs is not likely to cause serious health problems, but it should be cleaned up. The vacuum will put mercury vapor into the air and increase the likelihood of human exposure. It will break up the mercury into smaller beads and spread them around. Divert from drains, cracks and crevices. Keep children and others away from spill area to prevent the spread of contamination.