In July 2019, the United States Army Medical Research Institute of Infectious Disease (USAMRIID) ceased research operations after failing to meet biosafety requirements. USAMRIID is the lead research institute and only biosafety level (BSL) 4 laboratory for the Department of Defense that conducts medical biological research on high-risk pathogens. To better understand the implications of USAMRIID having their operations discontinued, it is critical to identify what a BSL is and how each level is designated.
The United States is home to several types of laboratories
that conduct medical research on a variety of infectious biological agents to
promote the development of new diagnostic tests, medical countermeasures, and
treatments. To promote safe medical research practices in laboratories studying
infectious agents, the Centers for Disease Control and Prevention (CDC) and the
National Institutes of Health have established four BSLs. The levels consist of
requirements that have identified as protective measures needed in the
laboratory setting to ensure the proper management of infectious agents to avoid
accidental exposure or release into the environment.
The BSL designations, ranked from lowest to the highest level of containment, are BSL-1, BSL-2, BSL-3, and BSL-4. The BSL designations outline specific safety and facility requirements to achieve the appropriate biosafety and biocontainment. The BSL is assigned based on the type of infectious agent on which the research is being conducted. The CDC has designed an infographic to help visualize the differences between each level. Each level builds on the previous level, adding additional requirements.
- Biosafety Level 1 (BSL-1): Conducts
research on agents that are not known to consistently cause disease in healthy
adults (e.g., Bacillus subtilis, Naegleria gruberi, and non-pathogenic E.
coli species). This type of BSL laboratory follows standard microbiological
practices and requires the fewest precautions due to the agents posing minimal
risk to laboratory personnel. A BSL-1 laboratory is not isolated from general
builds or human traffic. This level is found in undergraduate and secondary
educational training and teaching laboratories.
- Biosafety Level 2 (BSL-2): Conducts
research on indigenous agents that are present in the community and associated
with human disease posing a moderate-risk (e.g., HIV, hepatitis B virus, and Salmonella species). This level is
appropriate for research on any human-derived blood, bodily fluids, tissues, or
human cells in which the presence of an infectious agent may be unknown. Access
to a BSL-2 laboratory is restricted to trained personnel while research is
being conducted. This level is found in clinical, diagnostic, and teaching
Level 3 (BSL-3): Conducts research on indigenous or exotic agents with
potential for respiratory transmission, which may cause serious or potentially
lethal infection (e.g., Mycobacterium tuberculosis, Francisella tularensis, St. Louis encephalitis
virus). Due to the type of agents being handled, access is controlled in a
BSL-3 laboratory with a corridor that has two self-closing separating access
from the lab. This laboratory is also housed in a building with special
engineering safety features. This level is found in clinical,
diagnostic, teaching, and research laboratories.
- Biosafety Level 4 (BSL-4): Conducts
research on dangerous and exotic agents with a high-risk of causing
life-threatening disease, the possibility of aerosol transmission, and no known
treatment or therapy (e.g., Marbug virus, Congo-Crimean virus, Ebola virus). Entry into the BSL-4
laboratory is secure and limited, monitoring all persons in the facility with a
logbook. Laboratory personnel are required to complete a clothing change prior
to entry and shower on exit. This laboratory is customarily in a separate building
or isolated area with complex engineering safety features, such as filtered
ventilation systems and strict waste management requirements to prevent the
release of an agent. The construction of the build forms a sealed
internal shell for maximum containment. This level is found in select research laboratories.
implications of having the BSL-3 and BSL-4 laboratories at USAMRIID suspended
due to biosafety issues affect the Laboratory Response Network,
thereby potentially straining the nation’s biopreparedness infrastructure. USAMRIID is one of three
national laboratories responsible for specialized characterization of organisms
and select agents. Adherence to BSL requirements is paramount to maximize the
safety of laboratory personnel, the community, and ultimately the nation. Since
mid-August, there have been no updates regarding the discontinued research
operations at USAMRIID.
Note: This summary is neither extensive nor exhaustive of the requirements for each BSL. For additional information about BSL requirements, please see the Biosafety in Microbiological and Biomedical Laboratories guide by the U.S. Department of Health and Human Services.
Frankie Catalfumo is an epidemiologist with experience leading emergency preparedness and response operations in support of the federal government and international agencies relating to emerging infectious diseases and natural disasters. During his career, he has supported the Centers for Disease Control and Prevention, the Department of Defense, and the Pan American Health Organization to strengthen and enhance global health security.