Abstract: On September 20, 1999, Employee #1, a public school teacher, called in sick. Three days later, her family had her admitted to the hospital because of a persistent fever. At 12:35 p.m. on October 7, the hospital informed the school superintendent that Employee #1 had contracted Legionnaires' disease. Employee #1's school was ordered closed until Friday, October 15. The county public health officer was contacted and an outside consultant, Harding Lawson Associates, was hired to collect and sample the water for Legionella bacteria. On October 12, 1999, the county public health officer declared the school safe and for classes to resume. As of November 5, 1999, Employee #1 had not returned to work.