The four states require health-care providers to report pesticide-related illness to designated state agencies. State surveillance programs collect data on acute pesticide illness cases from various sources (e.g., physicians, poison control centers, workers compensation systems, and state and local government agencies) and classify cases based on the strength of evidence for pesticide exposure, health effects, and their causal relationship.6 CDC obtained data for the California cases from the California Department of Pesticide Regulation (CDPR), and data for the other three states from the Sentinel Event Notification System for Occupational Risks (SENSOR)-Pesticides program.* Case categories of definite, probable, possible, and suspicious from SENSOR-Pesticides and definite, probable, and possible from CDPR were included in the data analysis. An antimicrobial pesticide-related illness was defined as any acute adverse health effect resulting from exposure to an antimicrobial pesticide product. Health-care facilities were defined as hospitals, nursing and personal-care facilities, medical clinics, and other health service settings involving patient care.† Home health-care services were excluded. Data were analyzed for demographics, occupation, health effects, severity,‡ outcomes (e.g., hospitalization and lost work time), pesticide toxicity, active ingredients, and nature of exposure (e.g., type of activity, type of exposure, and PPE use).