After concern over the spread of Ebola grew in the U.S. this fall, many laboratorians spent hours online dutifully clicking through the Centers for Disease Control and Prevention (CDC) website, as well as reviewing guidance from other organizations, such as the World Health Organization (WHO), American Society for Microbiology (ASM), and others. What greeted laboratorians’ tired eyes was a patchwork of sometimes vague or even conflicting advice, leaving them with nagging questions about what was safe.
As the number of U.S. cases increased—from 2 in early August, to 9 by the beginning of November—CDC moved swiftly to offer extra help to hospitals and reassure the public. On October 20, the agency issued stricter guidelines for the personal protective equipment (PPE) that healthcare workers who treat patients with Ebola should wear. But for clinical labs, CDC has left the practical, detailed planning up to hospitals. Pressing laboratory-specific problems—such as which instruments to use, or how to decontaminate them—remain in the do-it-yourself category. At CLN press time, CDC’s recommendations for labs receiving samples from patients suspected of Ebola infection boiled down to following standard precautions, and as an added provision, using a certified class II biosafety cabinet or splash guard with PPE that protects skin and mucous membranes.
With the exception of phlebotomy, laboratorians are not exposed directly to patients; however, the laboratory’s instruments and environment create distinctive risks that are still not fully understood, noted Lance Peterson, MD, a clinical professor of pathology at the University of Chicago Pritzker School of Medicine. “The laboratory is unique in that we may need to be even more cautious in certain ways because we have the potential to create hazards that the patients themselves would not create,” he said. “There is every reason to believe that if you had a tube rupture in a centrifuge or other kind of aerosolization, such an exposure could lead to infection. So even though the virus is not aerosolized from the same standpoint as tuberculosis, if you create an aerosol in the laboratory, that risk is quite real.” A leading expert on infection control, Peterson is also director of the microbiology and infectious disease research program for the NorthShore University HealthSystem in Evanston, Illinois.
Looking for Answers
After Liberian national Thomas Eric Duncan became the first person in the U.S. diagnosed with the Ebola virus on September 30, anxiety soared in hospitals. AACC on October 7 held a webinar about laboratory practices for managing suspected Ebola specimens with CDC Medical Officer Nancy Cornish, MD. During the webinar, which attracted some 1,600 participants, Cornish enumerated the CDC resources that explain in great detail how laboratories should carry out precautions against infectious agents.
A number of agencies and offices in the federal government have promulgated standards related to infectious agents over the years, including CDC’s National Institute for Occupational Safety and Health (NIOSH) and Healthcare Infection Control Practices Advisory Committee (HICPAC), as well as the Occupational Safety and Health Administration (OSHA) (See Box, below). However, Cornish advised that labs not depend solely on the government’s infection control library, but confer as well with experts about their specific circumstances. She warned that some of those answers could be surprising. “Laboratories should consult with an industrial hygienist, as well as instrument manufacturers,” Cornish said. “In one case, we asked a manufacturer how an instrument could be decontaminated, and the representative responded: incinerate it.”
Also speaking during the webinar, Yale University Laboratory Medicine Professor Sheldon Campbell, MD, emphasized that labs would face continued uncertainty and the need for ongoing risk assessment. “Laboratories should plan for what’s reasonable right now, then reassess risk periodically,” he said. “To reconcile conflicts among guidance documents, you have to assess risk in your own setting and patient population, and recognize that zero risk is unattainable.”
Early Lessons Learned From Emory
Staffed by physicians, nurses, and laboratory technologists who volunteered for special duty, Emory University Hospital’s Serious Communicable Disease Unit in Atlanta has become known for treating the first two patients with Ebola in the U.S. Emory in 2002 established this specialized isolation unit in collaboration with CDC to care for patients with unidentified or highly contagious infectious diseases. In a Lab Medicine paper published in September, nine members of Emory’s laboratory medicine department outlined the laboratory testing protocols used to treat these patients (Lab Med 2014;45:e109–11).
According to a co-author of the article, Colleen Kraft, MD, medical director of the Emory Medical Laboratories microbiology section, the challenges the team faced can translate to other labs. Kraft advised a high level of caution and preparedness for any laboratory handling specimens from patients suspected of Ebola infection. “Based on our experience, I do not think that testing for patients with Ebola should be done in a central lab. There are enough guidelines, such as from WHO and the Australian Department of Health, that state that if you have Ebola virus in a line where you’re running other samples, you need to decontaminate that line. So a separate, enclosed lab is safest,” Kraft said. “I know that this could be an unpopular opinion, but patients with Ebola have extremely high viral loads and the handling of these specimens is critical.”
As part of the team caring for patients with Ebola at Emory, Kraft worked 60 hours per week in the unit, in addition to her regular full-time job. Her main message for labs: expect the unexpected. “Our team performed drills for 12 years, and we still didn’t really grasp how much work it would be until we were dealing with the real thing,” she said. “Caring for these patients takes an immense amount of personnel, containment practices, and training. And we’re also always watching each other to make sure that there is no safety protocol breach. This isn’t a casual investment.”
The Rush to Point-of-Care Testing
Based on reports from laboratories around the country posted on AACC listervs and from telephone interviews with CLN, it appears that many have already drawn up plans for treating patients suspected of having Ebola using only point-of-care (POC) instruments, both to limit transporting infectious samples and to avoid dealing with decontamination of complex and expensive central laboratory analyzers. Both ASM and New York State Department of Health guidelines suggest considering this option. CDC does not recommend limiting testing to POC, but assures labs that they can handle specimens safely following standard OSHA guidelines and using proper PPE.
Peterson recommended the New York State guideline as a practical starting point for labs. “Each laboratory will have to modify this and determine whether they will perform point-of-care testing at the patient bedside or carefully transfer specimens to one or two contained areas in the laboratory. We’re going to do the second,” he said. “But we are not going to put these specimens on the line. We will use several bench-top instruments that are locked shut so there is no potential aerosolization.” A key issue is how much the lab realistically can decontaminate, he added.
So far, manufacturers have been cautious when it comes to Ebola. One company circulated a letter to customers stating that while its “diagnostic instruments are generally designed to prevent formation of sample aerosols during testing, [the manufacturer] cannot provide assurance that dispersion of infectious disease agents, including Ebola virus, is completely prevented during specimen testing or if an instrument malfunctions or is misused.”
Patti Jones, PhD, clinical director of the chemistry and metabolic disease labs at Children’s Medical Center of Dallas and professor of pathology and medical laboratory science at UT Southwestern Medical Center, explained her lab’s plans as follows. Staff will use handheld POC instruments in patient rooms. However, healthcare workers working in a buddy system will use full isolation PPE—including powered air purifying respirators—with a multi-step system for donning and doffing. The POC instrument will be used for electrolytes, blood urea nitrogen, creatinine, ionized calcium, and blood gases. Other testing will be performed on a benchtop instrument in a special mini-lab.
Children’s Medical Center was designated as the hospital in Dallas where any infected children would be cared for after CDC discovered that eight had been in contact with Thomas Eric Duncan. The hospital created an isolation zone by clearing an intensive care unit wing with two negative-pressure patient rooms and a room two doors away to serve as the mini-lab.
Jones also noted that the primary handheld POC instrument the hospital chose was not FDA-cleared for performing prothrombin time testing outside of Coumadin monitoring, so her laboratory performed an extensive validation in order to be able to use it for patients with Ebola. “Doing this causes the test to be designated as high-complexity under CLIA,” Jones explained. “Therefore, only those individuals with appropriate licensure, training, and competency will be performing the test.”
Practice Your Plan
Experts agreed that laboratories should not be working alone, and that simply getting a plan on paper is not enough. “My advice is to get ahold of New York state guidance and then work with your emergency and infection control departments to identify two or three core people who will make the decision on who is a high-risk person,” Peterson said.
Practice is also essential, Peterson emphasized, especially to pick up on any roadblocks not specified in the plan. For example, Emory and other hospitals were surprised when waste disposal vendors balked at offering service. “You must practice your plan because those specimens are going to show up in the laboratory. It’s going to happen,” Peterson said.
A realistic and straightforward plan is also key, Campbell emphasized during the AACC webinar. “A simple plan that’s well-implemented by trained staff is better than a complex plan that’s badly implemented.”
AACC has curated a list of Ebola resources online, including guidance documents, fact sheets, an on-demand webinar, and a members-only Ebola listserv.
www.aacc.org/health-and-science-policy/ebola