Factors of interest. One of the most helpful tools available for performing a microbiological risk assessment is the risk group for the microbiological agent. A good starting point is review of the pathogen safety data sheet for the organism or toxin. However, simple reference to the risk group for a particular agent is insufficient in the conduct of a risk assessment. Other factors that should be considered, as appropriate, include: Pathogenicity of the agent, including drug resistance. Other factors that affect pathogenicity include potency of any toxins produced, presence of enzymes that help the agent avoid host defenses, oncogenicity, and allergenicity of the agent or its by- products Infectious dose. Potential outcome of exposure including the morbidity and mortality rate. Host range. Natural route of infection, including vectors. Excretion of microorganisms via urine, feces, or aerosols. Stability of the agent in the environment. Origin of the agent, endemicity. Any genetic manipulation of the organism that may extend the host range of the agent or alter the agent’s sensitivity to known, effective treatment regimens, (gain of function). Presence of a suitable host (human, animal, or plant). Local availability of effective prophylaxis or therapeutic interventions. Information available from animal studies and reports of laboratory-acquired infections or clinical reports. In addition to the risk group, factors affecting the use of the organism need to be considered in order to determine a risk management plan. Such factors include: Concentration of the agent and volume of concentrated material to be manipulated. Laboratory activities planned (e.g. sonication, aerosolization, centrifugation). Other routes of infection, resulting from laboratory manipulations (parenteral, airborne, ingestion). Experience, skill level, and health status of at-risk personnel. Use of animals. Location of the activities (e.g., laboratory, field, or animal facility). Preventative measures available including sanitary precautions, control of animal reservoirs or arthropod vectors, and movement of people or animals. On the basis of the information ascertained during the risk assessment, a risk management plan can be formulated. Appropriate engineering controls, administrative controls, and work practices can be developed. A biosafety containment level can be assigned to the planned work, appropriate personal protective equipment selected, and standard operatin...
