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Guidelines for Biosafety Laboratory Competency

CDC and the Association of Public Health Laboratories

Prepared by

Judy R. Delany, MS, MPH1

Michael A. Pentella, PhD2

Joyce A. Rodriguez, MS3

Kajari V. Shah, MS4

Karen P. Baxley5

David E. Holmes, PhD6

1Office of Surveillance, Epidemiology, and Laboratory Services, CDC

2University of Iowa, Iowa City, Iowa

3National Center for Environmental Health, CDC

4Association of Public Health Laboratories, Silver Spring, Maryland

5Office of Research Services, National Institutes of Health, Bethesda, Maryland

6Office of Safety, Health, and Environment, CDC

The material in this supplement originated in a multiagency, multisector workgroup that was sponsored by the Laboratory Science, Policy, and Practice Office, May Chu, PhD, Director, Office of Surveillance, Epidemiology and Laboratory Services, Stephen B. Thacker, MD, Director, and the Office of Safety, Health, and Environment, CDC, Paul J. Meechan, PhD, Director.

Corresponding preparer: Judy R. Delany, MS, MPH, Office of Surveillance, Epidemiology and Laboratory Services, CDC, 1600 Clifton Road., N.E., MS E-70, Atlanta, GA 30333. Telephone: 404-498-6488; Fax 404-498-6882; E-mail:


These guidelines for biosafety laboratory competency outline the essential skills, knowledge, and abilities required for working with biologic agents at the three highest biosafety levels (BSLs) (levels 2, 3, and 4). The competencies are tiered to a worker's experience at three levels: entry level, midlevel (experienced), and senior level (supervisory or managerial positions). These guidelines were developed on behalf of CDC and the Association of Public Health Laboratories (APHL) by an expert panel comprising 27 experts representing state and federal public health laboratories, private sector clinical and research laboratories, and academic centers. They were then reviewed by approximately 300 practitioners representing the relevant fields. The guidelines are intended for laboratorians working with hazardous biologic agents, obtained from either samples or specimens that are maintained and manipulated in clinical, environmental, public health, academic, and research laboratories.


Biosafety laboratories must ensure adequate safety conditions to avoid potential hazards associated with the handling of biologic materials, the manipulation of genomes, the creation of synthetic organisms, and the spread of multidrug-resistant bacteria, and threats of biologic terrorism. These guidelines define the essential competencies needed by laboratory personnel to work safely with biologic materials and other hazards that might be found in a biologic laboratory (e.g., those related to research animals, chemicals, radiologic materials, and the physical environment).

A successful laboratory safety program encompasses a continuous process of hazard recognition, risk assessment, and hazard mitigation. The risk for exposures, laboratory-acquired infections, and the unintended release of research or clinical materials to the environment should ultimately be reduced by ensuring the competency of laboratorians at all levels.

Competencies are measurable and include not only knowledge, skills, and abilities but also judgment and self-criticism (1,2). The establishment of competencies is the essential first step in developing training. Although the 2006 Pandemic All-Hazards Preparedness Act (PAHPA) legislation required the development of competency-based training curricula (3), an extensive national and international library search identified no existing set of competencies for laboratory biosafety to guide this development. This gap spurred the effort to develop such a set of competencies.


The primary purpose of these guidelines is to establish the behaviors and knowledge that laboratory workers at all levels should have to work safely with biologic materials. Other key issues addressed are the need for a well-designed workspace, knowledge of specific biologic agents and toxins, quality laboratory management practices, and an overall safety culture. This document provides essential competencies for incorporation into safety programs by laboratories that use biologic materials. These guidelines are designed for laboratorians practicing in the United States but also might have applicability for an international audience.


Several circumstances led to the development of biosafety competencies for practicing laboratorians. In 2006, PAHPA called for the assessment, development, delivery, and evaluation of competency-based training for biosafety in high containment laboratories (3). In 2008, CDC convened the Blue Ribbon Panel for issues of Clinical Laboratory Safety to address incidence of laboratory-acquired infection (4). Also in 2008, a Trans-Federal Task Force (5) was convened for federal agencies with laboratories to address biosafety and biosecurity in working with agents that pose a significant public health threat, whether they arise from nature, accidental exposure, or deliberate terrorist attacks. These efforts underscored the need to develop competency guidelines for laboratory biosafety.


In early 2009, a CDC Steering Committee, comprising CDC's Associate Directors for Laboratory Science and representatives from the Office of Workforce and Career Development, met to discuss the need for development of core competencies for laboratorians to work safely in all levels of biosafety containment. The CDC Steering committee recommended that the Association of Public Health Laboratories (APHL) lead this effort and identified those agencies and groups that should be involved. Each group or agency identified was invited to nominate a representative to participate in an expert panel to define biosafety competencies for laboratory workers. To ensure inclusiveness, CDC and APHL selected as members of this panel* practitioners representing all levels of biosafety practice from federal and state public health, government-funded research, military, private clinical, reference, and academic laboratories as well as experts in biosafety and competency development.

The expert panel working group was guided by the previous development of applied epidemiology competencies that used the framework developed by the Council on Linkages between Academia and Public Health Practice (COL) (6--8). A 3-day meeting of the expert panel in June 2009 initiated the work, which was carried out by subgroups that focused on developing competencies based on level of expertise (entry, mid, senior, and management) and biosafety level (BSL-2, BSL-3, and BSL- 4). To ensure that terminology was as consistent and widely understood as possible, a Blooms' taxonomy of educational objective terms was used (1). A draft document was developed and shared among the group. Subgroups continued to work via teleconference and WebEx (Cisco Systems, San Jose, California) document review to determine content and context of competencies and subcompetencies for presentation to the larger panel. A first complete draft of three sets of competencies, one for each biosafety level, for four tiers of practice (entry, mid, senior, and management) was submitted for review to the CDC Steering Committee in October 2009. Upon recommendation from the CDC Steering Committee and other reviewers, the expert panel decided to reorganize the competencies from the COL framework to that presented in the biosafety guide developed by CDC and the National Institutes of Health (Biosafety in Microbiological and Biomedical Laboratories, 5th edition [BMBL]) (9). This decision was made to facilitate the use of the competencies by practicing laboratorians.

In January 2010, a second meeting of a subset of the expert panel was held to revise the competencies on the basis of the BMBL framework for review by the entire expert panel. In March 2010, after reviewing all the documents, the full panel met and decided to combine the management and senior levels because the competencies were similar. The panel also determined that, although the risks and controls are different, competencies are essentially the same across all biosafety levels, allowing one competency statement to be applied in various ways across the entire field. Thus, the final draft provided for national review included a single set of competencies for use at all BSL levels at three tiers of laboratory practice: entry level, midlevel, and senior level.

Validation Process

The structured process included ample opportunity for national input from practicing and academic laboratorians to comment on the laboratory biosafety competencies. This process included the development of a survey tool (, Palo Alto, California) designed to collect opinion regarding the competencies as stated and to solicit comments and suggested revisions from respondents. The survey was publicized for several weeks via the working group members, professional association electronic distribution lists, and APHL's website. The survey tool was released in April 2010 and was available for comment for 6 weeks. A total of 274 responses were received from laboratorians representing all biosafety levels and types of laboratories (Table 1). In addition, several organizations, including NIH and ABSA, convened internal review committees to provide comment. These groups submitted a single survey response accompanied by recommended revisions.

All comments were collated and reviewed by a panel member who summarized for the entire panel. The summary of comments included basic demographic information regarding survey respondents, including domain of practice (e.g., academic, public health, and clinical) as well as information on the competencies which received the most and the fewest comments (Table 2). In addition, the summary report included agreement by skill domain and subdomain areas of the competencies. In June 2010, the expert panel met to review and address recommendations and concerns cited by the national survey respondents. Overall ≥88% of the respondents agreed with the draft competencies as written. Comments and suggested revisions by the <12% of reviewers who expressed some disagreement with the draft document were collated and discussed. When issues with the draft document stemmed from an apparent lack of clarity in the document, the competencies were modified to be clearer. Concerns that were considered substantive and those that were shared by multiple reviewers were given top priority. These competencies were revised to address the reviewers' concerns. In addition, after response from the laboratory community, changes were made to the domain structure, consolidating some domains and making slight modifications in others. Because ≥88% of the respondents to the initial draft agreed with the competencies as written, and the competencies with substantive or frequent comments were clarified or modified, the panel decided not to repeat the survey process with the revised competencies.

Guiding Principles

Culture of Safety

No regulation or guideline can ensure safe practices. Individual and organizational attitudes regarding safety will influence all aspects of safe practice, including willingness to report concerns, response to incidents, and communication of risk. Each organization should strive to develop a culture of safety that is open and nonpunitive, encourages questions, and is willing to be self-critical. Persons and organizations must be committed to safety, be aware of risks, behave in ways that enhance safety, and be adaptable. Scientists understand that practices should be refined as observations are made, hypotheses tested, findings published, and technical progress achieved. The same holds true for safety in the laboratory, which should evolve as experience is gained and as laboratory activities change. As laboratorians gain more knowledge over time concerning how to recognize and control hazards, the level of risk that is considered acceptable should become smaller, with the goal of moving continuously to eliminate or reduce risk to the lowest reasonably achievable level.

Laboratorians have both the responsibility to report concerns to management and the right to express concerns without fear of reprisal. Similarly, management has the responsibility to address concerns raised from any direction. A continuous process of hazard recognition, risk assessment, and hazard mitigation practices ensures that management and laboratory workers alike are aware of the issues and work together to maintain the highest standard of safety (10,11).


Although these guidelines address many hazards that might be encountered in a laboratory, they cannot be the sole resource used to develop a safety program. Similarly, if a laboratory does not use certain identified hazards (e.g., animals or radiologic materials), then those competencies will not be applicable. Ensuring that an effective safety culture exists in an organization requires the structuring of several components covered in this document. These include facilities, protocols, engineering controls, personal protective equipment, knowledge of risks being handled (agent- or toxin-specific), communications and signage, decontamination and waste management. The value of these guidelines is that they serve as a resource tool for education and training, which is the most effective way to build a safety culture.

Many laboratory-associated activities (e.g., shipping, animal housing, and manufacturing) were not included in this document. Depending on the nature of the work, these activities might be included when assessing safety competencies. A primary resource regarding safe use of biologic materials used across many fields is BMBL (9), which defines biosafety levels and describes safe practices, engineering, and controls for each biosafety level. The four domains specified in the following guidelines reflect the pattern established in the BMBL.

Broad Application

Biologic science is applicable to a wide range of activities. Biologic materials are used in private and government-supported research, clinical settings, academic and research institutions, diagnostic and drug development, animal science, agricultural development, and many adjunct areas, including nanotechnology and biochemistry. The competencies described in this document are broad enough to be considered for use in developing laboratory safety criteria in all fields that use biologic materials, but the guidelines are not intended to be all-inclusive. Federal, state, local, and institutional regulations, policies, and guidelines that address safety and security concerns also should be consulted while developing a site-specific safety program.

Competencies and Skill Domains

A competency is a measurable, documentable factor that involves not only skills that can be taught and developed but also the judgment and ability to recognize the limitations of the work environment and one's own skills and the skills of others in the laboratory. The verbs selected for each level of competency follow Bloom's Taxonomy (1), a standard construction for competency development, wherever appropriate. The verbs used correlate to an increasing level of skill, judgment, and responsibility at each of the three professional levels of practitioners. The specialized terms used in this document have been defined (Appendix A). Competencies are not tasks; however, a list of tasks can be developed by using these competencies as a guideline. The overall framework for the competency guidelines comprises four skill domains that follow the pattern established in BMBL: potential hazards, hazard controls, administrative controls, and emergency response and preparedness (Box); these competencies are outlined in detail (Appendix B).

Continuum of the Competencies

The competencies should be viewed as a matrix of varying levels of responsibility that are based on experience and risk. Novices to the field begin at the entry level but should have the education and experience appropriate to understand and apply the principles of biologic safety relevant to their field of work. As a person gains experience, he or she might advance to a midlevel position and eventually to a senior-level position within a specific biosafety level. Depending on the size, scope, and mission of the organization, titles and roles can vary (Table 3).

Risks associated with each biosafety level increase from BSL-2 through BSL-4 (9), and each increased level requires additional practices and engineering controls to mitigate those risks. Therefore, a laboratorian who is competent to work at a senior level with BSL-2 agents must begin again at the entry level to build competencies when starting to work with BSL-3 agents, and similarly for starting to work with BSL-4 agents. The amount of time required to become competent in each domain at each biosafety level will vary widely depending on the scope of the work and a person's knowledge, skills, abilities, opportunity for experience, and judgment.


Laboratory safety is a collaborative effort that, to be successful, should include participation of all persons involved. The appropriate breadth of collaboration depends on the hazards in use in a given laboratory. Internal groups necessary for collaboration might include human resources, facility engineering, occupational and environmental health and safety, biosafety, security, occupational medicine, risk management, and emergency preparedness personnel. External collaborators should include first responders (e.g., fire, police, and emergency medical personnel) and hospitals or other health-care facilities that receive patients.

Regularly soliciting input from laboratorians who work directly with biologic materials is critical. Often laboratorians recommend possible work changes that might increase safety directly or indirectly through developing more efficient methods. Ideally, an organization can assess and implement these practices while keeping documentation current.

Intended Use

These guidelines define the expected essential competencies for working safely with biologic and other hazardous laboratory materials. Laboratory personnel can use this information to enhance their existing comprehensive safety programs. Each organization must tailor its comprehensive safety program to address the organization's specific needs and use all available resources. Different organizations might find different uses for these guidelines, depending on their structure and guidelines already in existence. The application of these guidelines will vary widely depending on the field (e.g., agriculture, industry, research, academia, military, health-care, clinical, or professional organizations). Their intended use will also vary by category of user, which might include the following persons and responsibilities:

  • practitioners
    --- assess current skills and establish goals,
    --- plan training and educational needs,
    --- meet biosafety competencies relevant to each step of an advancing career path
  • employers
    --- develop training plans for employees,
    --- establish the safety portions of position descriptions and job qualifications,
    --- assess the capability of an organization to operate safely with biologic materials;
  • educators in sciences and safety --- develop coursework to meet the needs of biologic laboratory safety --- incorporate the elements of these competencies into existing curricula (5).

These guidelines should be read in full before beginning to apply their contents. The competency development and review process indicated that words often have different meanings to persons in different fields and minimizing the overlap between the sections of the document and other regulatory and guidance documents requires a comprehensive effort. Unless otherwise noted, the definitions of the terms used in this report (Appendix A) were created by the working group or represent nuances or modifications to compiled online dictionaries or BMBL.


CDC and APHL intend to disseminate these guidelines broadly throughout a variety of professional organizations and newsletters, including, but not limited to, scientific, educational, safety, and public health. The competencies will be presented at meetings of public health practitioners and biologic safety professionals (e.g., ABSA). The guidelines also will be maintained on CDC's website ( and on APHL's website (


These guidelines outline the essential expectations for behaviors and knowledge of laboratory workers necessary to work safely with biologic materials at all levels of the profession in the life sciences. The development of these guidelines is a first step toward defining comprehensive safety competencies in biologic laboratories. These guidelines reflect a range of past experiences and will be reviewed periodically and refined as additional experience is gained. The guidelines can be used as a resource to develop educational goals, training standards, safety assessments, professional development, and certification. Every organization using these competencies should regularly review and improve its practices and documents with an eye toward continual reduction of the risks involved in working with biologic and other hazardous laboratory materials. Training is not limited to the initial instruction received at the start of a laboratory worker's employment but is continuous and refreshed periodically. Some professions or organizations that were contributors to these guidelines, including AALAS and the Council of State and Territorial Epidemiologists, also have addressed biologic safety practices (12,13).


These guidelines are based in part on contributions provided by the more than 300 practitioners who reviewed these guidelines and by Kathleen Miner, PhD, School of Public Health, Emory University, Atlanta, Georgia; Roderick Frazier, DSc, Ritchard Parry, MS, Laboratory Science, Policy, and Practice Program Office, Office of Surveillance, Epidemiology and Laboratory Services, CDC.


  1. Bloom BS. Taxonomy of educational objectives, handbook I: the cognitive domain. New York, NY: David McKay Co Inc.; 1956.
  2. Merriam SB, Caffarella RS, Baumgartner LM. Self-directed learning. In: Learning in adulthood: a comprehensive guide. 3rd ed. San Francisco, CA: Jossey-Bass; 2007.
  3. Congressional Research Service. Pandemic and All-Hazards Preparedness Act, S.3678. Washington, DC: Congressional Research Service; 2006. Available at Accessed March 22, 2011.
  4. Miller JM. Guidelines for safe work practices in human and animal medical diagnostic laboratories. MMWR 2011. In press.
  5. US Department of Health and Human Services, US Department of Agriculture. Report of the Trans-Federal Task Force on Optimizing Biosafety and Biocontainment Oversight. Washington, DC: Agriculture Research Service; 2009. Available at Accessed March 22, 2011.
  6. Birkhead G, Jac D, Miner K, Lemmings, J, Koo D. Developing competencies for applied epidemiology: from process to product. Public Health Rep 2008(Suppl 1);123:73.
  7. Birkhead G, Koo D. Professional competencies for applied epidemiologists: a roadmap to a more effective epidemiologic workforce. Journal of Public Health Management and Practice 2006;12:501--4.
  8. Public Health Foundation, Council on Linkages Between Academia and Public Health Practice. Core competencies for public health professionals. Washington, DC: Public Health Foundation; 2010. Available at Accessed March 22, 2011.
  9. Chosewood LC, Wilson DE, eds. Biosafety in microbiological and biomedical laboratories. 5th ed. Washington, DC: US Department of Health and Human Services, CDC, National Institutes of Health; 2009.
  10. Occupational Safety and Health Administration. Safety and Health Management Systems eTools. Washington, DC: US Department of Labor, Occupational Safety and Health Administration; 2010. Available at Accessed March 22, 2011.
  11. Swarz G, ed. Safety culture and effective safety management. Chapter 2. Chicago, IL: National Safety Council; 2000.
  12. American Association of Laboratory Animal Science. Biosafety officers and animal facility directors indicate interest in the AALAS Animal Biocontainment Training Program. JAALAS 2009;48:440--1.
  13. CDC, Council of State and Territorial Epidemiologists. Development of applied epidemiology competencies. Atlanta, GA: Council of State and Territorial Epidemiologists; US Department of Health and Human Services, CDC; 2010. Available at Accessed March 22, 2011.

* A list of the members of the expert panel appears on page 23.

Organizations and agencies included the American Association for Laboratory Animal Science (AALAS), American Biological Safety Association (ABSA), American Clinical Laboratory Association, American Society of Microbiology, Association of Public Health Laboratories, Eagleson Institute, Emory University, Frontline Foundation, Food and Drug Administration, Georgia State University, National Institutes of Health, Occupational Safety and Health Administration, University of Texas Medical Branch, U.S. Department of Agriculture, and U.S. Department of Defense.

TABLE 1. Number and percentage of survey respondents, by selected demographic characteristics --- Biosafety Level (BSL) Competency Survey, United States, 2010




Job classification

Entry-level laboratorian



Mid-level laboratorian



Senior-level laboratorian



Biosafety professional



BSL level










Domain of practice

Local or state public health



Federal agency






Academic research









TABLE 2. Percentage of domain responses --- Biosafety Level (BSL) Competency Survey, United States, 2010

Three skill domains with fewest comments

Approval %

Hazard controls: engineering controls --- equipment (primary barriers)


Emergency preparedness and response: emergency response drills and exercises


Emergency preparedness and response: exposure prevention and hazard mitigation


Three skill domains with most comments

Approval %

Potential hazards: biologic materials


Hazard controls: decontamination and laboratory waste management


Potential hazards: radiologic materials


Agreement by domain

Agreement %

Potential hazards



Research animals


Biologic materials


Chemical materials


Radiologic materials


Physical environment


Hazard controls

Personal protective equipment (primary barriers)


Engineering controls --- equipment (primary barriers)


Facilities --- (secondary barrier) BSL-2 & BSL-3


Decontamination and laboratory waste management


Administrative controls

Hazard communication and signage


Guideline and regulation compliance


Safety program management


Medical surveillance


Risk assessment


Risk associated with laboratory procedures


Emergency preparedness and response

Emergencies and incident response


Exposure prevention and hazard mitigation


Emergency response drills and exercises


BOX. Competency domains framework

Domain I:

Potential hazards

Biologic materials

Research animals

Chemical materials

Radiologic materials

Physical environment

Domain II:

Hazard controls

Personal protective equipment

Engineering controls -- equipment (primary barriers)

Engineering controls -- facility (secondary barriers)

Decontamination and waste control management

Domain III:

Administrative controls

Hazard communication and signage

Guidelines and regulatory compliance

Safety program management

Occupational health -- medical surveillance

Risk management

Domain IV:

Emergency preparedness and response

Emergencies and incident response

Exposure prevention and hazard mitigation

Emergency response -- exercises and drills

TABLE 3. Roles of biosafety laboratory personnel, by field and level --- Biosafety Level Competency Survey, United States, 2010


Entry level


Senior level

Academia or research

Technician, research associate, or specialist

Principal investigator, laboratory manager, postdoctoral student, or senior or staff scientist

Principal investigator or branch or division manager

Clinical setting

Laboratory scientist or medical technologist

Chief/lead scientist or medical technologist, laboratory specialist, or laboratory manager

Laboratory manager, chief technologist, or hospital or clinic director

Biosafety Laboratory Competencies Working Group

Expert Panel Members

Conveners: Judy R. Delany, MS, MPH, Office of Surveillance, Epidemiology and Laboratory Services, CDC, Atlanta, Georgia, Eva J. Perlman, MPH, Association of Public Health Laboratories, Silver Spring, Maryland.

Project Manager: Kajari V. Shah, MPH, National Center for Public Health Laboratory Leadership, Association of Public Health Laboratories, Silver Spring, Maryland.

Facilitators: Reed Deschler, MA, AlignOrg Solutions and Pandora Ray, MPH, National Center for Public Health Laboratory Leadership, Association for Public Health Laboratories, Silver Spring, Maryland.

Expert Panel Members: Karen P. Baxley, Office of Research Services, National Institutes of Health, Bethesda, Maryland; Eric Blank, DrPH, Missouri State Public Health Laboratory (retired), Jefferson City, Missouri; Karen B. Byers, MS, Dana Farber Cancer Institute, Boston, Massachusetts; Nicole Duffee, DVM, PhD, American Association for Laboratory Animal Science, Memphis, Tennessee; Anne-Sophie Brocard, PhD, Dept of Pathology University of Texas Medical Branch, Galveston, Texas; Norman Crouch, PhD, State Public Health Laboratory, Minnesota Department of Health, Minneapolis, Minnesota (retired); Eilyn N. Fabregas, MS, US Department of Agriculture and Agricultural Research Service, Beltsville Agricultural Research Center, Beltsville, Maryland; Richard J. Green, MSc, Frontline Foundation, Atlanta, Georgia; David Holmes, PhD, Office of Safety, Health, and Environment, CDC, Atlanta, Georgia; Bill Homovec, MPH, American Clinical Laboratory Association, Burlington, North Carolina; Peter C. Iwen, PhD, Nebraska Public Health Laboratory and Professor, Pathology and Microbiology, University of Nebraska Medical Center, Omaha, Nebraska; Sean G. Kaufman, MPH, Center for Public Health Preparedness and Research, Rollins School of Public Health, Emory University, Atlanta, Georgia; Kathleen Keyes, National Center for Emerging and Zoonotic Infectious Diseases, CDC, Atlanta, Georgia; Wendi L Kuhnert, PhD, National Center For Immunization and Respiratory Diseases, CDC, Atlanta, Georgia; Clete Lewis, Quest Diagnostics, Inc., Madison, New Jersey; Tod J. Merkel, PhD, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland; Richard J. Muller, Jr., Georgia State University, Atlanta, Georgia; Michael Pentella, PhD, Iowa State Hygienic Laboratory, College of Public Health, University of Iowa, Iowa City, Iowa; Dee Pettit, PhD, Division of Consolidated Laboratory Services, Richmond, Virginia; Nathaniel Powell, DVM, National Center for Preparedness, Detection, and Control of Infectious Diseases, CDC, Atlanta, Georgia; Joyce Rodriguez, MS, National Center for Environmental Health, CDC, Atlanta, Georgia; Anthony Sanchez, PhD, National Center for Emerging and Zoonotic Infectious Diseases, CDC, Atlanta, Georgia; Mary Ann Sondrini, Eagleson Institute, Sanford, Maine; Richard Y. Wang, DO, National Center for Environmental Health, CDC, Atlanta, Georgia; Yun F (Wayne) Wang, MD, PhD, Grady Memorial Hospital, Emory University School of Medicine, Atlanta, Georgia; Dionne Williams, MPH, Directorate of Enforcement Programs, Occupational Safety and Health Administration, District of Columbia; Catherine Wilhelmsen, DVM, PhD, Army Medical Research Institute for Infectious Diseases, US Department of Defense, Fredricks, MD.

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