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To the Editor: The unprecedented number of Ebola virus disease (EVD) cases in western Africa has compelled the world to consider experimental and off-label therapeutics to mitigate the current outbreak. For clinicians, approved drugs are an attractive solution because of known safety profiles and availability. Oral lamivudine (GlaxoSmithKline, Brentford, UK), a US Food and Drug Administration–approved anti-HIV drug, has been suggested as a possible antiviral agent against Ebola virus (EBOV). In September 2014, a Liberian physician, Dr. Gorbee Logan, reported positive results while treating EVD with lamivudine (1). Thirteen of 15 patients treated with lamivudine survived presumed EVD and were declared virus free. Clinical confirmation of EVD in these cases remains to be verified. Our laboratory had previously assessed this antiretroviral compound in drug screens against EBOV and observed no discernable antiviral activity. However, given the recent testimonials regarding lamivudine effectiveness in treating EBOV-infected patients in Africa, we conducted additional studies to determine whether our previous assertion that lamivudine lacked any direct antiviral activity was correct. Lamivudine is a nucleoside analog reverse transcription inhibitor of HIV and hepatitis B virus that acts as a synthetic cytidine analog. Incorporation of the active triphosphate form into viral DNA results in chain termination. Studies have demonstrated that lamivudine is a weak inhibitor of mammalian α, β, and γ DNA polymerases (2). Lamivudine would not be expected to inhibit the replication of a negative-strand RNA virus. The activity of lamivudine against EBOV infection was evaluated in a cell-based ELISA with 1995 isolate EBOV H. sapiens-tc/COD/1995/Kikwit (EBOV/Kik) (3). Three cell lines were tested: Vero E6 (African green monkey kidney, ATCC CRL-1586), Hep G2 (human hepatoma, ATCC HB-8065), and human monocyte-derived macrophages. Macrophages were generated by treating CD14+ cells for 7 days with macrophage colony–stimulating factor and conditioned medium. Cells were treated with compounds in 3-, 4-, or 8- point dose response curves with 2-fold dilutions starting at 80 µmol/L or 320 µmol/L oral lamivudine. Toremifene (T7204–5MG; Sigma-Aldrich, St. Louis, MO, USA) was used as a positive control for activity against EBOV and tested at 2-fold dilutions starting at 25 µmol/L. One hour after drug addition, the cells were infected at a multiplicity of infection of 0.5 or 1 with EBOV/Kik. Experiments were run on duplicate plates or the entire experiment was run on 2 separate days. At 48 hours after infection, cells were formalin-fixed and stained with a primary antibody against EBOV (antibodies against viral matrix protein or glycoprotein) and a secondary antibody (Alexa-488 or horseradish peroxidase). No direct antiviral effect for lamivudine was observed at concentrations ≤320 µmol/L in Vero E6 cells (Table). Because optimal efficacy of the drug requires phosphorylation, lack of activity may be caused by poor phosphorylation in Vero E6 cells (6). Therefore, we also assessed HepG2 cells and primary human monocyte–derived macrophages sensitive to EBOV infection. Toremifene was included as a positive control. Toremifene is a US Food and Drug Administration–approved drug that was reported to have direct antiviral activity in cell culture and to protect mice infected with mouse-adapted EBOV (3). As expected, toremifene inhibited EBOV at low micromolar concentrations (Table). Table Inhibitory effects of test compounds on Ebola virus replication* Finally, we assessed the antiviral activity of the compounds against a recent isolate prototype from the current outbreak, EBOV H. sapiens-tc/GIN/2014/Gueckedou-C05 (EBOV/Gue) to test whether inhibition of EBOV/Gue by lamivudine was different from that of the reference Kikwit strain. In contrast to a known active compound (toremifene), lamivudine showed no direct antiviral activity. The current data suggest that lamivudine does not directly inhibit EBOV RNA polymerase or replication of the virus. Systemic and off-target effects, while not previously described, might be possible. To address this possibility, we plan to assess lamivudine in the mouse model of EVD and will report these findings when available. However, on the basis of these in vitro tests, there is no foundation for recommending lamivudine for treatment of EVD in human patients.

One-sentence summary for table of contents: Training should include theoretical consideration of biocontainment principles, practical hands-on training, and mentored on-the-job experience., Construction of several new Biosafety Level 4 (BSL-4) laboratories and expansion of existing operations have created an increased international demand for well-trained staff and facility leaders. Directors of most North American BSL-4 laboratories met and agreed upon a framework for leadership and training of biocontainment research and operations staff. They agreed on essential preparation and training that includes theoretical consideration of biocontainment principles, practical hands-on training, and mentored on-the-job experiences relevant to positional responsibilities as essential preparation before a person’s independent access to a BSL-4 facility. They also agreed that the BSL-4 laboratory director is the key person most responsible for ensuring that staff members are appropriately prepared for BSL-4 operations. Although standardized certification of training does not formally exist, the directors agreed that facility-specific, time-limited documentation to recognize specific skills and experiences of trained persons is needed.

Ebola virus (EBOV) causes acute hemorrhagic fever that is fatal in up to 90% of cases in both humans and nonhuman primates. No vaccines or treatments are available for human use. We evaluated the effects in nonhuman primates of vaccine strategies that had protected mice or guinea pigs from lethal EBOV infection. The following immunogens were used: RNA replicon particles derived from an attenuated strain of Venezuelan equine encephalitis virus (VEEV) expressing EBOV glycoprotein and nucleoprotein; recombinant Vaccinia virus expressing EBOV glycoprotein; liposomes containing lipid A and inactivated EBOV; and a concentrated, inactivated whole-virion preparation. None of these strategies successfully protected nonhuman primates from robust challenge with EBOV. The disease observed in primates differed from that in rodents, suggesting that rodent models of EBOV may not predict the efficacy of candidate vaccines in primates and that protection of primates may require different mechanisms. bola virus (EBOV) and Marburg virus (MBGV), which make up the family Filoviridae, cause severe hemorrhagic

A global outbreak of severe acute respiratory syndrome (SARS) caused by a novel coronavirus began in March 2003. The rapid emergence of SARS and the substantial illness and death it caused have made it a critical public health issue. Because no effective treatments are available, an intensive effort is under way to identify and test promising antiviral drugs. Here, we report that recombinant human interferon (IFN)-β 1a potently inhibits SARS coronavirus replication in vitro.

For the past 2 years, a team of investigators from the Centers for Disease Control and Prevention (CDC) has collaborated with scientists from the National Institutes of Health (NIH), the Food and Drug Administration, the Department of Defense (DOD), academic centers, and international partners to undertake a research agenda on variola virus, the etiologic agent of smallpox. Objectives of the program derive from a 1999 Institute of Medicine report that addressed the scientific needs for live variola virus (1). Progress in addressing these objectives has been peer reviewed annually by both a select committee organized by CDC and the World Health Organization (WHO) Advisory Committee on Variola Virus Research (2,3). A summary of accomplishments from the first year’s efforts was published in 2001 (4). The events of September 11, 2001, coupled with the use of Bacillus anthracis as a bioterrorist weapon of mass destruction, have substantially increased concerns that variola virus may be similarly used and have added a sense of urgency to production of a new smallpox vaccine and to carrying out the smallpox research agenda. This report provides an update on progress during 2001.

DOI: 10.3201/eid1507.081523, Directors of all major BioSafety Level 4 (BSL-4) laboratories in the United States met in 2008 to review the current status of biocontainment laboratory operations and to discuss the potential impact of a proposed 2-person security rule on maximum-containment laboratory operations. Special attention was paid to the value and risks that would result from a requirement that 2 persons be physically present in the laboratory at all times. A consensus emerged indicating that a video monitoring system represents a more efficient, economical standard; provides greater assurance that pathogens are properly manipulated; and offers an increased margin of employee safety and institutional security. The 2-person security rule (1 to work and 1 to observe) may decrease compliance with dual responsibilities of safety and security by placing undue pressure on the person being observed to quickly finish the work, and by placing the observer in the containment environment unnecessarily.

To facilitate rapid, unbiased, differential diagnosis of infectious diseases, we designed GreeneChipPm, a panmicrobial microarray comprising 29,455 sixty-mer oligonucleotide probes for vertebrate viruses, bacteria, fungi, and parasites. Methods for nucleic acid preparation, random primed PCR amplification, and labeling were optimized to allow the sensitivity required for application with nucleic acid extracted from clinical materials and cultured isolates. Analysis of nasopharyngeal aspirates, blood, urine, and tissue from persons with various infectious diseases confirmed the presence of viruses and bacteria identified by other methods, and implicated Plasmodium falciparum in an unexplained fatal case of hemorrhagic feverlike disease during the Marburg hemorrhagic fever outbreak in Angola in 2004–2005.

Viral Haemorrhagic Fevers is a compact and highly readable monograph written by Collin Howard, an authoritative and veteran virologist with hands-on practical experience in this field. This volume is highly satisfying on a variety of levels. Self-contained chapters deal with each of the 4 taxonomic viral families (Flaviviridae, Arenaviridae, Bunyaviridae, and Filoviridae), which make up the category of viral hemorrhagic fever agents. The properties of each virus family are presented in terms of molecular virology and replication strategy, followed by the epidemiology, clinical presentation, and treatment options. Cross-referencing to other chapters is kept to a minimum, enhancing the readability of the text. The information is reasonably current, with the exception of the current Marburg outbreak in Angola. For each virus, the author offers his candid assessment of the available treatment options. My only quibble is that I do not share his pessimism that effective vaccines will not be developed and distributed in the near future. The author made a conscious decision to avoid encyclopedic referencing to enhance readability. On occasion, this results in bold statements that the specialist might wish had been referenced. One example is the discussion of Whitewater Arroyo virus and its probable (but contentious) role in 3 fatal cases of hemorrhagic fever from 1999 to 2000. Another is a statement that infection of endothelial cells is a critical event in the pathogenesis of Ebola virus, which, to my knowledge, has never been adequately documented. The text is enhanced by electron micrographs of representative agents, photographs of rodent reservoirs in their native habitat, maps of geographic distributions, and schematic representations of genome organization and replication strategies. The legend to Figure 2 in the Filovirus chapter compares Marburg and Ebola viruses, but only 1 image (which I recognize to be Marburg) is displayed. The author states that this book was directed "primarily at healthcare workers, clinicians, and microbiologists wishing to gain a rapid overview of these widely varying agents." This book should appeal to that audience, and also to a wider audience of persons interested in the public health ramifications of these serious viral diseases in their geographic niches as well as their potential to cause disease in industrialized nations, either when imported by returning travelers or deliberately released in an act of terrorism. These aspects of viral hemorrhagic fever agents are discussed in both the introductory and concluding chapters of the book. A nice touch was the inclusion of a short annotated bibliography of books for the lay audience dealing with the history of these agents, plus a second list of specialized textbooks of more interest to the practicing virologist. Other appendices list useful Web sites and a capsule explanation of how biocontainment facilities are designed to deal with these fearsome pathogens. There is something for everyone in this book; I will keep my copy handy, next to my desk.

Microbe: Are We Ready for the Next Plague? by Alan Zelicoff and Michael Bellomo is a comprehensive, yet succinct, account of the threat to public health posed by microbial pathogens. What distinguishes this book from the surfeit of recent books hyping the threat of bioterrorism are its balanced perspective and elucidation of naturally emerging disease threats, such as severe acute respiratory syndrome (SARS) or West Nile virus, as exotic entities requiring a rapid and effective response; Mother Nature is quite the bioterrorist herself. Early recognition that an event has occurred is key to containment of the nascent epidemic. The authors provide sufficient basic science background to bring the uninitiated up to speed on a variety of exotic and recently introduced microbes in engagingly titled chapters such as "The Birds that Fell from the Sky" (West Nile), "Corona of Death" (SARS), and "Something in the Water" (Cryptosporidium). In addition, they describe hantavirus pulmonary syndrome, mad cow disease, and Legionnaires' disease in the context of recent public health emergencies. The authors also explain why both smallpox and anthrax are more than abstract concerns as agents of bioterrorism, on the basis of weaponization history, intrinsic attributes, and realistic scenarios. An account of the 1970 smallpox outbreak, which occurred in Aralsk, Kazakhstan, as a consequence of open air testing of a smallpox weapon by the Soviets is an eye-opener; there should be no doubts about capability and intent after reading this story. The scenarios are well chosen and informative; they highlight the importance of early recognition that "something has happened" and breaking the disease cycle close to the index case. The unifying theme of the book is the importance of syndrome-based surveillance in achieving this goal. The authors dismiss BIOWATCH (air-monitoring devices to detect and identify microbes in aerosol clouds) as a well-intended but expensive "work in progress," to put it charitably. BIOSENSE is a national surveillance system that they say has not been implemented in any substantive way. I reluctantly find myself in agreement with these assessments and receptive to their suggestions to implement an emerging diseases reporting system based on syndromic reporting. Healthcare providers recognize syndromes, not microbial diseases. How long did it take to recognize monkeypox in 2003? The hantavirus associated with lethal pulmonary syndrome in New Mexico in 1993 was recognized only when the pattern emerged among previously healthy young adults living in rustic conditions on a Navajo reservation. The authors describe a product they dub Syndromic Reporting Information System (SYRIS) as a "beta test" product that has been deployed on a limited, regional basis and promises to provide a near instantaneous map of syndromic reports and to comply with all Centers for Disease Control and Prevention requirements for electronic reporting systems. Like most good ideas, simplicity is central to the SYRIS concept; it is likely to succeed because participating doctors, nurses, and veterinarians (most of the exotic pathogens are zoonoses) can report syndromic occurrences in 15 seconds or less and will be rewarded with instantaneous feedback and tailored reports and alarms. While this section does read a bit like an infomercial, the concept is sound and worthy of serious consideration by public health officials and policy makers. This book is the best of its genre and is recommended for anyone interested in understanding and managing the risks associated with emerging microbial threats.