Rats and mice are often found living in and under school buildings. Rodents contaminate stored food with their droppings and urine, and spread the deadly hantavirus pulmonary syndrome, an infectious disease linked to more than 27 recent deaths in the United States. Fire ants build their nests on school grounds. These nests often contain more than 100,000 ants. During recess and physical education classes, children are often stung when they step into nests while playing.
Fire ants can inflict hundreds of painful stings to children.
More than half of the U.S. population, including children, is allergic to poison ivy, poison oak and poison sumac. Contact with each of these plants causes severe skin irritation, intense itching and burning, as well as blistering. A Wisconsin school district banned the use of herbicides to control poison ivy and other weeds. The decision was later reversed when a student had to undergo a 22-day course of steroids to treat a poison ivy rash. Other weeds, such as crabgrass and dandelions, can cause injury when children trip over them on playgrounds and sports fields.