Biocontainment Units: Moving to the Next Phase of Evolution

Interest and belief in the concept of “containment care” for highly hazardous communicable diseases has evolved over several decades, since the establishment of the specialized isolation facility at the US Army Medical Research Institute of Infectious Diseases (USAMRIID) in the early 1970s. Multiple factors have influenced the evolution in clinical management guidelines of such diseases over time, as we have discussed previously. ¹ The army's original unit was modeled after and included engineering controls analogous to those in a Biosafety Level-4 (BSL-4) laboratory. Three biocontainment units derived from that model were active in the United States prior to the 2013-2016 Ebola outbreak in West Africa: University of Nebraska's Biocontainment Unit (NBU, Omaha, NE), Emory University's Serious Communicable Disease Unit (SCDU, Atlanta, GA), and the National Institute of Allergy and Infectious Diseases' Special Clinical Studies Unit (SCSU, Bethesda, MD).

Healthcare facilities in the United States had previously cared safely for cases of Marburg and Lassa viruses,^2,3 sometimes without knowledge of the diagnosis until after the patient was discharged or had died. However, medical evacuation of cases of Ebola virus disease (EVD) to the United States during the 2013-2016 West Africa Ebola outbreak, and the nosocomial spread to 2 nurses caring for an imported case, ⁴ appears to have led to a permanent change in perception in the medical community and US government regarding the optimal venue in which to manage patients infected with Ebola and other highly hazardous communicable pathogens.

During the West African outbreak, given the challenge of managing EVD patients in a conventional healthcare facility, ⁵ the Centers for Disease Control and Prevention (CDC) developed a 3-tiered system for the care of patients suspected of or confirmed as having EVD. ⁶ A few dozen institutions, including 1 in each of the Department of Health and Human Services' (HHS) 10 regions, would develop biocontainment units similar to those described above. ⁷ These Ebola treatment centers (ETCs) would be able to care for a patient with EVD throughout the continuum of disease. Other hospitals, known as Ebola assessment hospitals, would have the ability to receive and isolate a patient with possible EVD and care for that patient safely for up to 96 hours while awaiting transport of the patient to an Ebola treatment center. Remaining hospitals would be designated “frontline facilities” and would be expected to identify, triage, and isolate an EVD patient safely, pending transfer of the patient to more robust care. At the same time, the National Ebola Training and Education Center (NETEC) was founded, with funding from the Assistant Secretary of Preparedness and Response and the CDC (both in HHS) and led by the 3 nongovernment facilities that had cared successfully for Ebola victims during the West Africa outbreak: the University of Nebraska, Emory University, and New York's Bellevue hospital. ⁸ The NETEC assumed the mission of training and advising the member institutions of this 3-tiered system. In addition, a research network (the Special Pathogens Research Network, or SPRN) that includes the 10 regional facilities was established under the NETEC as a proactive measure to conduct research on, and optimize the use of, countermeasures during future outbreaks.

In 2005, representatives from the 4 specialized isolation units in existence at the time published a consensus document ⁹ that defined a “biocontainment patient care unit” as a clinical facility “designed to minimize nosocomial transmission of highly contagious and hazardous diseases by incorporating engineering and safety measures used in biosafety level (BSL) 3 and 4 containment laboratories.”^9(p352) Such measures included “negative air pressure ventilation systems for entire units, disinfectant pass-through boxes, restricted access, and other infrastructure and administrative controls not typically found in routine clinical settings.”^9(p352) Furthermore, the group made recommendations on optimal standards that should be applied when designing such a unit. Facilities in Europe have offered similar ideas on standards for such units as well as infection control practices for highly pathogenic infectious diseases.^10,11

The capabilities of different facilities around the globe vary considerably and continue to evolve. ¹² A 2018 meeting held in Bethesda, Maryland, brought together representatives from US, European, and Asian biocontainment units to share their diverse experiences managing patients requiring high-level isolation. We believe that was a useful next step in the ongoing dissemination of knowledge and biocontainment process improvement.

Since the West Africa outbreak, in addition to the 10 regional NETEC-SPRN centers in the United States, many other large medical centers have established their own biocontainment units. We thus believe that the concept of biocontainment unit care has reached a level of maturity and diversity such that it is time to reconsider the establishment of certain consensus recommendations for the operation of such units, along the lines of the 2005 consensus meeting. This process could begin in the United States, but it might also be applicable internationally. Consensus targets might include the reassessment of specific capabilities and engineering controls required to achieve designation as a biocontainment unit, as well as the pathogens and diseases that might warrant care in such units.

We are not proposing formal surveys as might be conducted by the Joint Commission or inspections such as those conducted by the CDC of facilities conducting research on select agents. In fact, the NETEC has successfully demonstrated its ability to conduct evaluations of units on a voluntary basis; these evaluations include peer-to-peer on-site observations of operations, infection control practices, capability gaps, and administrative controls and serve a quality improvement and assistance, rather than a regulatory, function. The NETEC has no regulatory or oversight mandate. We are recommending, however, that the time is right for reconsidering and defining those basic capabilities that a facility should possess in order to be designated a biocontainment unit.

Under our proposal, individual institutions would have the flexibility, and in fact would be encouraged, to develop their units beyond such a core baseline according to their own needs. Moreover, we advocate for expanding and formalizing a program of assistance, evaluation, and quality improvement nationally and, perhaps, internationally.

In summary, we propose the expansion of a national consortium/partnership among facilities with biocontainment units along similar lines already established by the NETEC. In addition to meeting certain baseline criteria established by the consortium to earn the designation as a biocontainment unit, membership in the consortium would carry with it an expectation of information sharing about unit capabilities, as well as any experience gained from managing patients. Thus, all members would participate in an iterative process that ultimately would be expected to improve readiness, patient care, and infection prevention and control practices.