Clinical Laboratory Worker Exposures to Select Agents: A Collaborative Approach

BACKGROUND: Biological agents that pose a severe threat to human and animal health are included in the Federal Select Agent (SA) Program. Laboratory worker exposures to SAs continue to occur, despite published safety guidelines. We describe lessons learned from three events that occurred in Minnesota in 2015. METHODS: Brucellosis and melioidosis are reportable to the Minnesota Department of Health (MDH); suspect isolation of the agents is submittable to the MDH Public Health Laboratory (PHL), and when confirmed, to the SA Program. Identifying possible worker exposure is required by the SA Program. Follow-up, including post-exposure prophylaxis (PEP) and monitoring for seroconversion, was performed per CDC guidelines. MDH PHL and epidemiology staff worked with clinical laboratory leadership and Infection Prevention (IP) staff to assess exposures and assign risk levels. MDH epidemiology provided PEP recommendations to the IP and Employee Health (EH) Nurse. EH facilitated PEP prescriptions. Standardized surveys were used to track PEP compliance and symptom occurrence. MDH epidemiology coordinated blood draws following the serologic monitoring schedule, and with PHL staff, coordinated collection of serum samples for shipment to CDC, where serologic testing was performed. RESULTS: Brucella suis was isolated from a patient in Clinical Lab A, and a second patient in Lab B; Burkholderia pseudomallei was isolated from a third patient in Lab A. Examining the isolates on an open bench, subculturing, and preparing specimens for identification exposed laboratorians. In Lab A, B. suis isolation resulted in 11 high risk and 7 low risk exposures; B. pseudomallei isolation resulted in 6 low risk exposures; 2 laboratorians were exposed to both isolates. In Lab B, B. suis isolation resulted in 4 high risk and 5 low risk exposures. Serologic and symptom monitoring was recommended for all exposed laboratorians; 1 laboratorian, exposed to both bacteria, declined serologic monitoring. Thirty laboratorians agreed to serologic monitoring, 5 missed 1 blood draw. No seroconversions occurred. Symptom monitoring was completed by all exposed laboratorians; no concerning symptoms were reported. PEP was recommended and completed for 15 high risk exposures. Based on lessons learned, clinical laboratories modified lab procedures to decrease risk of exposure.   CONCLUSIONS:  SA exposures are complicated, requiring the coordination of multiple departments and agencies. Completing recommended guidelines for PEP and serologic and symptom monitoring can be difficult. Strong relationships between health departments, clinical laboratory leadership, IP staff, EH staff, exposed workers, and CDC is critical for successful completion of recommendations and preventing illness.