Ethical alternatives to experiments with novel potential pandemic pathogens

Gain-of-function research and model organisms in biology

So-called 'gain-of-function' (GOF) research is virological research that results in a virus substantially more virulent or transmissible than its wild antecedent. GOF research has been subject to ethical analysis in the past, but the methods of GOF research have to date been underexamined by philosophers in these analyses. Here, we examine the typical animal used in influenza GOF experiments, the ferret, and show how despite its longstanding use, it does not easily satisfy the desirable criteria for an animal model We then discuss the limitations of the ferret model, and how those epistemic limitations bear on ethical and policy questions around the risks and benefits of GOF research. We conclude with a reflection on how philosophy of science can contribute to ethical and policy debates around the risks, benefits and relative priority of life sciences research.

Source toxicity characteristics of short- and medium-chain chlorinated paraffin in multi-environmental media: Product source toxicity, molecular source toxicity and food chain migration control through silica methods

Short and medium-chain chlorinated paraffin (SCCP/MCCP) have been widely studied because of their extensive environmental hazards. In this study, product source toxicity, molecular source toxicity and food chain migration of SCCP and MCCP in multi-environmental media were comprehensively considered. The additive combination of SCCP and MCCP in the air, water and soil environment was adjusted, and PVC, PU and rubber products with the lowest source toxicity were screened. The source toxicity of SCCP and MCCP in the water environment was inhibited by design of the feed additive addition scheme (highest inhibition was 16.29 %), and the source toxicity of SCCP and MCCP in the soil environment was affected by different field management measures (highest inhibition was 38.22 %). A forage fertilizer addition plan, a cattle feed addition plan and a special population healthy complementary food regulation plan were developed to prevent the migration step by step and absorption of SCCP and MCCP in the terrestrial food chain. In addition, by means of density functional theory and analysis of key amino acid residues, the mechanism of toxicity difference between SCCP and MCCP was analyzed from the level of chemical interaction, and rationality of the inhibition scheme designed in this study was verified.

Reconsidering the need for gain-of-function research on enhanced potential pandemic pathogens in the post-COVID-19 era

The dual-use risk of infectious disease research using enhanced potential pandemic pathogens (ePPP), particularly gain-of-function (GOF) research, has been debated since 2011. As of now, research is supported on the condition that the research plan is reviewed and the actual experiment is supervised. However, the kinds of research conducted and what benefits they have brought to our society have not been adequately verified. Nevertheless, due to the COVID-19 pandemic that began at the end of 2019 and caused numerous deaths and wide economic disruption, the importance of infectious disease control from an international perspective has been recognized. Although complete control of the pandemic is still far off, positive signs include generating epidemiological trends based on genome analysis, therapeutic drug and vaccine development, clinical patient management, and public health policy interventions. In this context, the time has come to reconsider the true significance of GOF research on ePPP and the state of research governance in the post-COVID-19 era. In particular, the risks of such research are clearer than before, whereas its benefits seem less apparent. In this paper, we summarize the history of discussions on such GOF research, its significance in the light of the current COVID-19 pandemic, and the direction we shall take in the future.

Integrating evolutionary aspects into dual-use discussion: the cases of influenza virus and enterohemorrhagic Escherichia coli

Research in infection biology aims to understand the complex nature of host–pathogen interactions. While this knowledge facilitates strategies for preventing and treating diseases, it can also be intentionally misused to cause harm. Such dual-use risk is potentially high for highly pathogenic microbes such as Risk Group-3 (RG3) bacteria and RG4 viruses, which could be used in bioterrorism attacks. However, other pathogens such as influenza virus (IV) and enterohemorrhagic Escherichia coli (EHEC), usually classified as RG2 pathogens, also demonstrate high dual-use risk. As the currently approved therapeutics against these pathogens are not satisfactorily effective, previous outbreaks of these pathogens caused enormous public fear, media attention and economic burden. In this interdisciplinary review, we summarize the current perspectives of dual-use research on IV and EHEC, and further highlight the dual-use risk associated with evolutionary experiments with these infectious pathogens. We support the need to carry out experiments pertaining to pathogen evolution, including to gain predictive insights on their evolutionary trajectories, which cannot be otherwise achieved with stand-alone theoretical models and epidemiological data. However, we also advocate for increased awareness and assessment strategies to better quantify the risks-versus-benefits associated with such evolutionary experiments. In addition to building public trust in dual-use research, we propose that these approaches can be extended to other pathogens currently classified as low risk, but bearing high dual-use potential, given the particular pressing nature of their rapid evolutionary potential.

The Social Risks of Science

Many instances of scientific research impose risks, not just on participants and scientists but also on third parties. This class of social risks unifies a range of problems previously treated as distinct phenomena, including so-called bystander risks, biosafety concerns arising from gain-of-function research, the misuse of the results of dual-use research, and the harm caused by inductive risks. The standard approach to these problems has been to extend two familiar principles from human subjects research regulations-a favorable risk-benefit ratio and informed consent. We argue, however, that these moral principles will be difficult to satisfy in the context of widely distributed social risks about which affected parties may reasonably disagree. We propose that framing these risks as political rather than moral problems may offer another way. By borrowing lessons from political philosophy, we propose a framework that unifies our discussion of social risks and the possible solutions to them.

Might SARS-CoV-2 Have Arisen via Serial Passage through an Animal Host or Cell Culture?: A potential explanation for much of the novel coronavirus' distinctive genome

Despite claims from prominent scientists that SARS-CoV-2 indubitably emerged naturally, the etiology of this novel coronavirus remains a pressing and open question: Without knowing the true nature of a disease, it is impossible for clinicians to appropriately shape their care, for policy-makers to correctly gauge the nature and extent of the threat, and for the public to appropriately modify their behavior. Unless the intermediate host necessary for completing a natural zoonotic jump is identified, the dual-use gain-of-function research practice of viral serial passage should be considered a viable route by which the novel coronavirus arose. The practice of serial passage mimics a natural zoonotic jump, and offers explanations for SARS-CoV-2's distinctive spike-protein region and its unexpectedly high affinity for angiotensin converting enzyme (ACE2), as well as the notable polybasic furin cleavage site within it. Additional molecular clues raise further questions, all of which warrant full investigation into the novel coronavirus's origins and a re-examination of the risks and rewards of dual-use gain-of-function research.

Dual-Use and Infectious Disease Research

Despite rapid advance in the prevention, diagnosis, and treatment, infectious diseases remain a central challenge for global health policy. In the twenty-first century, the life sciences—including microbiology, virology, and immunology—have been marshalled as key tools in the fight against infectious disease, and the promotion of global health. Rapid advance in these fields, however, has given rise to the “dual-use dilemma,” when one and the same piece of scientific research or technology has the capacity to help or harm humanity. While not unique to fields that address infectious disease, contemporary cases of dual-use research are largely identified in the context of the life sciences. In this chapter I outline the debate about dual-use research in the life sciences, in particular the ethics of dual-use research. After a historical overview of the dual-use dilemma in the twenty-first century, I examine ethical issues in attempting to trade off the risks and benefits of dual-use research. I address how we select alternative, less risky experiments; translational issues arising for dual-use research; and political commitments to realise the benefits and mitigate the risks arising from such research. I then discuss the governance of dual-use research, before concluding with a brief discussion on priority setting in infectious disease research as a path forward for policymakers.

Linking Biodiversity with Health and Well-being: Consequences of Scientific Pluralism for Ethics, Values and Responsibilities

This paper investigates the ethical implications of research at the interface between biodiversity and both human and animal health. Health and sanitary crises often lead to ethical debates, especially when it comes to disruptive interventions such as forced vaccinations, quarantine, or mass culling of domestic or wild animals. In such debates, the emergence of a "Planetary health ethics" can be highlighted. Ethics and accountability principles apply to all aspects of scientific research including its technological and engineering applications, regardless of whether they are considered "hard sciences", such as state-of-the-art technology in the fields of medicine, veterinary medicine, agronomy, or environment, or "soft", such as local or global governance, health, socio-ecosystems, and the environment. Ethical reflection in the interdisciplinary field of biodiversity and health requires the examination of relevant scientific domains, such as biology, ecology, evolution, human medicine, animal medicine, anthropology, and law, and their epistemology and representation as well as scientific pluralism, which is crucial to establish genuine interdisciplinarity. Navigating the ethics-scape necessitates going beyond the hierarchy of science by recognising that scientific knowledge has implications for both scientific and non-scientific perspectives on the study of nature. The example of a Nipah virus outbreak is used to illustrate how the so-called "modern epidemiological" approach often focuses on risk factors associated with individual behavioural characteristics or collective practices, whereas the so-called "eco-social" approach focuses on global, socio-economic, and environmental factors that are the contextual causes of the health problem affecting the community. "Modern epidemiologists" aim to "correct" individual or practice factors using a "minimal set" of ethics, whereas "eco-social" scientists have to act systemically, which requires integrated research that acknowledges scientific pluralism, avoids the hierarchy of sciences, but accepts the pluralism of ethics and values.

Infectious Disease Threats in the Twenty-First Century: Strengthening the Global Response

The world has developed an elaborate global health system as a bulwark against known and unknown infectious disease threats. The system consists of various formal and informal networks of organizations that serve different stakeholders; have varying goals, modalities, resources, and accountability; operate at different regional levels (i.e., local, national, regional, or global); and cut across the public, private-for-profit, and private-not-for-profit sectors. The evolving global health system has done much to protect and promote human health. However, the world continues to be confronted by longstanding, emerging, and reemerging infectious disease threats. These threats differ widely in terms of severity and probability. They also have varying consequences for morbidity and mortality, as well as for a complex set of social and economic outcomes. To various degrees, they are also amenable to alternative responses, ranging from clean water provision to regulation to biomedical countermeasures. Whether the global health system as currently constituted can provide effective protection against a dynamic array of infectious disease threats has been called into question by recent outbreaks of Ebola, Zika, dengue, Middle East respiratory syndrome, severe acute respiratory syndrome, and influenza and by the looming threat of rising antimicrobial resistance. The concern is magnified by rapid population growth in areas with weak health systems, urbanization, globalization, climate change, civil conflict, and the changing nature of pathogen transmission between human and animal populations. There is also potential for human-originated outbreaks emanating from laboratory accidents or intentional biological attacks. This paper discusses these issues, along with the need for a (possibly self-standing) multi-disciplinary Global Technical Council on Infectious Disease Threats to address emerging global challenges with regard to infectious disease and associated social and economic risks. This Council would strengthen the global health system by improving collaboration and coordination across organizations (e.g., the WHO, Gavi, CEPI, national centers for disease control, pharmaceutical manufacturers, etc.); filling in knowledge gaps with respect to (for example) infectious disease surveillance, research and development needs, financing models, supply chain logistics, and the social and economic impacts of potential threats; and making high-level, evidence-based recommendations for managing global risks associated with infectious disease.

Infectious Disease Threats in the Twenty-First Century: Strengthening the Global Response

The world has developed an elaborate global health system as a bulwark against known and unknown infectious disease threats. The system consists of various formal and informal networks of organizations that serve different stakeholders; have varying goals, modalities, resources, and accountability; operate at different regional levels (i.e., local, national, regional, or global); and cut across the public, private-for-profit, and private-not-for-profit sectors. The evolving global health system has done much to protect and promote human health. However, the world continues to be confronted by longstanding, emerging, and reemerging infectious disease threats. These threats differ widely in terms of severity and probability. They also have varying consequences for morbidity and mortality, as well as for a complex set of social and economic outcomes. To various degrees, they are also amenable to alternative responses, ranging from clean water provision to regulation to biomedical countermeasures. Whether the global health system as currently constituted can provide effective protection against a dynamic array of infectious disease threats has been called into question by recent outbreaks of Ebola, Zika, dengue, Middle East respiratory syndrome, severe acute respiratory syndrome, and influenza and by the looming threat of rising antimicrobial resistance. The concern is magnified by rapid population growth in areas with weak health systems, urbanization, globalization, climate change, civil conflict, and the changing nature of pathogen transmission between human and animal populations. There is also potential for human-originated outbreaks emanating from laboratory accidents or intentional biological attacks. This paper discusses these issues, along with the need for a (possibly self-standing) multi-disciplinary Global Technical Council on Infectious Disease Threats to address emerging global challenges with regard to infectious disease and associated social and economic risks. This Council would strengthen the global health system by improving collaboration and coordination across organizations (e.g., the WHO, Gavi, CEPI, national centers for disease control, pharmaceutical manufacturers, etc.); filling in knowledge gaps with respect to (for example) infectious disease surveillance, research and development needs, financing models, supply chain logistics, and the social and economic impacts of potential threats; and making high-level, evidence-based recommendations for managing global risks associated with infectious disease.

Structure-Guided Identification of a Nonhuman Morbillivirus with Zoonotic Potential

Morbilliviruses infect a broad range of mammalian hosts, including ruminants, carnivores, and humans. The recent eradication of rinderpest virus (RPV) and the active campaigns for eradication of the human-specific measles virus (MeV) have raised significant concerns that the remaining morbilliviruses may emerge in so-called vacated ecological niches. Seeking to assess the zoonotic potential of nonhuman morbilliviruses within human populations, we found that peste des petits ruminants virus (PPRV)-the small-ruminant morbillivirus-is restricted at the point of entry into human cells due to deficient interactions with human SLAMF1-the immune cell receptor for morbilliviruses. Using a structure-guided approach, we characterized a single amino acid change, mapping to the receptor-binding domain in the PPRV hemagglutinin (H) protein, which overcomes this restriction. The same mutation allowed escape from some cross-protective, human patient, anti-MeV antibodies, raising concerns that PPRV is a pathogen with zoonotic potential. Analysis of natural variation within human and ovine SLAMF1 also identified polymorphisms that could correlate with disease resistance. Finally, the mechanistic nature of the PPRV restriction was also investigated, identifying charge incompatibility and steric hindrance between PPRV H and human SLAMF1 proteins. Importantly, this research was performed entirely using surrogate virus entry assays, negating the requirement for in situ derivation of a human-tropic PPRV and illustrating alternative strategies for identifying gain-of-function mutations in viral pathogens.IMPORTANCE A significant proportion of viral pandemics occur following zoonotic transmission events, where animal-associated viruses jump species into human populations. In order to provide forewarnings of the emergence of these viruses, it is necessary to develop a better understanding of what determines virus host range, often at the genetic and structural levels. In this study, we demonstrated that the small-ruminant morbillivirus, a close relative of measles, is unable to use human receptors to enter cells; however, a change of a single amino acid in the virus is sufficient to overcome this restriction. This information will be important for monitoring this virus's evolution in the field. Of note, this study was undertaken in vitro, without generation of a fully infectious virus with this phenotype.

The Silver Lining in Gain-of-Function Experiments with Pathogens of Pandemic Potential

Half a decade after the contentious "gain-of-function" (GOF) debate of 2012 that followed experimentation showing that highly pathogenic avian influenza virus could become mammalian transmissible, it is possible to reflect on the arguments for and against this type of research. In this essay we argue that GOF-type experiments have already produced important information not available from any other source while also providing information on pathogenesis and the requirements for optimizing strains for vaccine production. We analyze the moral arguments against GOF and find them less compelling for a variety of reasons ranging from the uncertainty of risk-benefit analysis to the reduced likelihood of accidents given the enhanced biosafety and biosecurity protocols currently in place. In our view the most important consequence of the GOF debate is that it brought renewed attention to biosafety protocols and ushered innovation in answering the relevant biological questions with greater safety. We conclude that GOF experiments should go forward provided that necessary biosafety and biosecurity conditions are in place.

A Hospital-Based Committee of Moral Philosophy to Revive Ethics

The Méditerranée Infection Foundation's primary goal is supporting a research hospital for the treatment of infectious diseases in Marseille. The main objective of this innovative center is to understand the mechanisms of contagion and face them. The Foundation will include a committee on moral philosophy that will accompany and supervise biomedical research. This is not a conventional ethics committee, frequently giving rise to a board's bureaucratic excesses, which might slow down creative biomedical clinical research without necessarily restricting abuses. Moral philosophy, however, can handle contemporary biomedical issues. In all its diversity, this discipline is able to enrich the debate on medical issues, thanks to many philosophical currents such as deontological ethics and consequentialism. The purpose of this committee is therefore to advance reflection on the bioethical issues encountered in biomedical research in infectious diseases, while respecting the precepts of moral philosophy.

A New Approach to Evaluating the Risk-Benefit Equation for Dual-Use and Gain-of-Function Research of Concern

In the twenty-first century, biology faces a problem that has previously vexed other disciplines such as physics, namely the prospect that its knowledge domain could be used to generate biological agents with altered properties that enhanced their weapon potential. Biological weapons bring the additional dimension that these could be self-replicating, easy to manufacture and synthesized with commonly available expertise. This resulted in increasing concern about the type of research done and communicated, despite the fact that such research often has direct societal benefits, bringing the dual-use dilemma to biology. The conundrum of dual use research of concern was crystallized by the so-called "gain-of-function" type of experiments in which avian influenza viruses were endowed with new properties in the laboratory such as increased virulence and the capacity for mammalian transmission. After more than a decade of intensive discussion and controversy involving biological experiments with dual-use potential, there is no consensus on the issue except for the need to carry out such experiments in the safest conditions possible. In this essay, we review the topic with the hindsight of several years and suggest that instead of prescribing prohibitions and experimental limitations the focus should be on the importance of scientific questions at hand. We posit that the importance of a scientific question for medical and scientific progress provides a benchmark to determine the acceptable level of risk in biological experimentation.

Ethical and Philosophical Considerations for Gain-of-Function Policy: The Importance of Alternate Experiments

The Department of Health and Human Services Framework for Guiding Funding Decisions about Proposed Research Involving Enhanced Potential Pandemic Pathogens (PPPs) contains a series of principles for governing the funding and conduct of gain-of-function (GOF) research resulting in the creation of PPPs. In this article, I address one of these principles, governing the replacement of GOF research with alternate experiments. I argue that the principle fails to address the way that different experiments can promote the same values as those promoted by GOF research resulting in PPPs. I then address some objections to this claim, and provide policy recommendations moving forward.

Why Do Exceptionally Dangerous Gain-of-Function Experiments in Influenza?

This chapter makes the case against performing exceptionally dangerous gain-of-function experiments that are designed to create potentially pandemic and novel strains of influenza, for example, by enhancing the airborne transmissibility in mammals of highly virulent avian influenza strains. This is a question of intense debate over the last 5 years, though the history of such experiments goes back at least to the synthesis of viable influenza A H1N1 (1918) based on material preserved from the 1918 pandemic. This chapter makes the case that experiments to create potential pandemic pathogens (PPPs) are nearly unique in that they present biosafety risks that extend well beyond the experimenter or laboratory performing them; an accidental release could, as the name suggests, lead to global spread of a virulent virus, a biosafety incident on a scale never before seen. In such cases, biosafety considerations should be uppermost in the consideration of alternative approaches to experimental objectives and design, rather than being settled after the fact, as is appropriately done for most research involving pathogens. The extensive recent discussion of the magnitude of risks from such experiments is briefly reviewed. The chapter argues that, while there are indisputably certain questions that can be answered only by gain-of-function experiments in highly pathogenic strains, these questions are narrow and unlikely to meaningfully advance public health goals such as vaccine production and pandemic prediction. Alternative approaches to experimental influenza virology and characterization of existing strains are in general completely safe, higher throughput, more generalizable, and less costly than creation of PPP in the laboratory and can thereby better inform public health. Indeed, virtually every finding of recent PPP experiments that has been cited for its public health value was predated by similar findings using safe methodologies. The chapter concludes that the unique scientific and public health value of PPP experiments is inadequate to justify the unique risks they entail and that researchers would be well-advised to turn their talents to other methodologies that will be safe and more rewarding scientifically.

Seasonality in risk of pandemic influenza emergence

Influenza pandemics can emerge unexpectedly and wreak global devastation. However, each of the six pandemics since 1889 emerged in the Northern Hemisphere just after the flu season, suggesting that pandemic timing may be predictable. Using a stochastic model fit to seasonal flu surveillance data from the United States, we find that seasonal flu leaves a transient wake of heterosubtypic immunity that impedes the emergence of novel flu viruses. This refractory period provides a simple explanation for not only the spring-summer timing of historical pandemics, but also early increases in pandemic severity and multiple waves of transmission. Thus, pandemic risk may be seasonal and predictable, with the accuracy of pre-pandemic and real-time risk assessments hinging on reliable seasonal influenza surveillance and precise estimates of the breadth and duration of heterosubtypic immunity.

Gain-of-Function Research: Ethical Analysis

Gain-of-function (GOF) research involves experimentation that aims or is expected to (and/or, perhaps, actually does) increase the transmissibility and/or virulence of pathogens. Such research, when conducted by responsible scientists, usually aims to improve understanding of disease causing agents, their interaction with human hosts, and/or their potential to cause pandemics. The ultimate objective of such research is to better inform public health and preparedness efforts and/or development of medical countermeasures. Despite these important potential benefits, GOF research (GOFR) can pose risks regarding biosecurity and biosafety. In 2014 the administration of US President Barack Obama called for a "pause" on funding (and relevant research with existing US Government funding) of GOF experiments involving influenza, SARS, and MERS viruses in particular. With announcement of this pause, the US Government launched a "deliberative process" regarding risks and benefits of GOFR to inform future funding decisions-and the US National Science Advisory Board for Biosecurity (NSABB) was tasked with making recommendations to the US Government on this matter. As part of this deliberative process the National Institutes of Health commissioned this Ethical Analysis White Paper, requesting that it provide (1) review and summary of ethical literature on GOFR, (2) identification and analysis of existing ethical and decision-making frameworks relevant to (i) the evaluation of risks and benefits of GOFR, (ii) decision-making about the conduct of GOF studies, and (iii) the development of US policy regarding GOFR (especially with respect to funding of GOFR), and (3) development of an ethical and decision-making framework that may be considered by NSABB when analyzing information provided by GOFR risk-benefit assessment, and when crafting its final recommendations (especially regarding policy decisions about funding of GOFR in particular). The ethical and decision-making framework ultimately developed is based on the idea that there are numerous ethically relevant dimensions upon which any given case of GOFR can fare better or worse (as opposed to there being necessary conditions that are either satisfied or not satisfied, where all must be satisfied in order for a given case of GOFR to be considered ethically acceptable): research imperative, proportionality, minimization of risks, manageability of risks, justice, good governance (i.e., democracy), evidence, and international outlook and engagement. Rather than drawing a sharp bright line between GOFR studies that are ethically acceptable and those that are ethically unacceptable, this framework is designed to indicate where any given study would fall on an ethical spectrum-where imaginable cases of GOFR might range from those that are most ethically acceptable (perhaps even ethically praiseworthy or ethically obligatory), at one end of the spectrum, to those that are most ethically problematic or unacceptable (and thus should not be funded, or conducted), at the other. The aim should be that any GOFR pursued (and/or funded) should be as far as possible towards the former end of the spectrum.

Mechanistic Models of Infectious Disease and Their Impact on Public Health

From the 1930s through the 1940s, Lowell Reed and Wade Hampton Frost used mathematical models and mechanical epidemic simulators as research tools and to teach epidemic theory to students at the Johns Hopkins Bloomberg School of Public Health (then the School of Hygiene and Public Health). Since that time, modeling has become an integral part of epidemiology and public health. Models have been used for explanatory and inferential purposes, as well as in planning and implementing public health responses. In this article, we review a selection of developments in the history of modeling of infectious disease dynamics over the past 100 years. We also identify trends in model development and use and speculate as to the future use of models in infectious disease dynamics.

Influenza A virus transmission via respiratory aerosols or droplets as it relates to pandemic potential

Many respiratory viruses of humans originate from animals. For instance, there are now eight paramyxoviruses, four coronaviruses and four orthomxoviruses that cause recurrent epidemics in humans but were once confined to other hosts. In the last decade, several members of the same virus families have jumped the species barrier from animals to humans. Fortunately, these viruses have not become established in humans, because they lacked the ability of sustained transmission between humans. However, these outbreaks highlighted the lack of understanding of what makes a virus transmissible. In part triggered by the relatively high frequency of occurrence of influenza A virus zoonoses and pandemics, the influenza research community has started to investigate the viral genetic and biological traits that drive virus transmission via aerosols or respiratory droplets between mammals. Here we summarize recent discoveries on the genetic and phenotypic traits required for airborne transmission of zoonotic influenza viruses of subtypes H5, H7 and H9 and pandemic viruses of subtypes H1, H2 and H3. Increased understanding of the determinants and mechanisms of respiratory virus transmission is not only key from a basic scientific perspective, but may also aid in assessing the risks posed by zoonotic viruses to human health, and preparedness for such risks.

The ethics of biosafety considerations in gain-of-function research resulting in the creation of potential pandemic pathogens

This paper proposes an ethical framework for evaluating biosafety risks of gain-of-function (GOF) experiments that create novel strains of influenza expected to be virulent and transmissible in humans, so-called potential pandemic pathogens (PPPs). Such research raises ethical concerns because of the risk that accidental release from a laboratory could lead to extensive or even global spread of a virulent pathogen. Biomedical research ethics has focused largely on human subjects research, while biosafety concerns about accidental infections, seen largely as a problem of occupational health, have been ignored. GOF/PPP research is an example of a small but important class of research where biosafety risks threaten public health, well beyond the small number of persons conducting the research.We argue that bioethical principles that ordinarily apply only to human subjects research should also apply to research that threatens public health, even if, as in GOF/PPP studies, the research involves no human subjects. Specifically we highlight the Nuremberg Code's requirements of 'fruitful results for the good of society, unprocurable by other methods', and proportionality of risk and humanitarian benefit, as broad ethical principles that recur in later documents on research ethics and should also apply to certain types of research not involving human subjects. We address several potential objections to this view, and conclude with recommendations for bringing these ethical considerations into policy development.

Gain-of-Function Research and the Relevance to Clinical Practice

The ongoing moratorium on gain-of-function (GOF) research with highly pathogenic avian influenza virus, severe acute respiratory syndrome coronavirus, and Middle East respiratory syndrome coronavirus has drawn attention to the current debate on these research practices and the potential benefits and risks they present. While much of the discussion has been steered by members of the microbiology and policy communities, additional input from medical practitioners will be highly valuable toward developing a broadly inclusive policy that considers the relative value and harm of GOF research. This review attempts to serve as a primer on the topic for the clinical community by providing a historical context for GOF research, summarizing concerns about its risks, and surveying the medical products that it has yielded.

Mapping influenza transmission in the ferret model to transmission in humans

The controversy surrounding 'gain-of-function' experiments on high-consequence avian influenza viruses has highlighted the role of ferret transmission experiments in studying the transmission potential of novel influenza strains. However, the mapping between influenza transmission in ferrets and in humans is unsubstantiated. We address this gap by compiling and analyzing 240 estimates of influenza transmission in ferrets and humans. We demonstrate that estimates of ferret secondary attack rate (SAR) explain 66% of the variation in human SAR estimates at the subtype level. Further analysis shows that ferret transmission experiments have potential to identify influenza viruses of concern for epidemic spread in humans, though small sample sizes and biological uncertainties prevent definitive classification of human transmissibility. Thus, ferret transmission experiments provide valid predictions of pandemic potential of novel influenza strains, though results should continue to be corroborated by targeted virological and epidemiological research.

DOI:http://dx.doi.org/10.7554/eLife.07969.001

Every year, thousands of people develop influenza (flu). After being infected by the influenza virus, the immune systems of most people adapt to fight off the virus if it is encountered again. However, there are many different strains of influenza, and new strains constantly evolve. Therefore, although someone may have developed resistance to one previously encountered strain, they can still become ill if another strain infects them.

Different strains of the influenza virus have different abilities to spread between people and make them ill. One way that scientists assess whether a particular strain of influenza is a threat to people is by studying ferrets, which develop many of the same flu symptoms as humans. However, questions have been raised over how accurately ferret studies reflect whether a particular virus strain will spread between humans.

Controversy has also arisen over experiments in which ferrets are infected with genetically engineered strains of influenza that mimic how a strain that has evolved in birds could adapt to cause a pandemic in humans. In 2014, the United States government suggested that such research should be temporarily stopped until more is known about the risks and usefulness of these studies. Now, Buhnerkempe, Gostic et al. have compared the results of 240 ferret and human studies that aimed to assess how easily strains of influenza spread. Specifically, the studies looked at how often a healthy ferret or human became ill when exposed to an animal or human infected with a particular strain of influenza.

The results of the ferret transmission studies matched well with transmission patterns observed in human studies. Ferret studies that assessed how the influenza virus is transmitted through the air via sneezes and coughs were particularly good at predicting how the virus spreads in humans. But Buhnerkempe, Gostic et al. caution that ferret studies are not always accurate, partly because they involve small numbers of animals, which can skew the results. There also needs to be more effort to standardize the procedures and measurements used in ferret studies.

Still, the analysis suggests that overall, ferret studies are a useful tool for making an initial prediction of which influenza strains may cause a pandemic in humans, which can then be verified using other methods.

DOI:http://dx.doi.org/10.7554/eLife.07969.002

Modeling human influenza infection in the laboratory

Influenza is the leading cause of death from an infectious cause. Because of its clinical importance, many investigators use animal models to understand the biologic mechanisms of influenza A virus replication, the immune response to the virus, and the efficacy of novel therapies. This review will focus on the biosafety, biosecurity, and ethical concerns that must be considered in pursuing influenza research, in addition to focusing on the two animal models - mice and ferrets - most frequently used by researchers as models of human influenza infection.

Fitness Inference from Short-Read Data: Within-Host Evolution of a Reassortant H5N1 Influenza Virus

We present a method to infer the role of selection acting during the within-host evolution of the influenza virus from short-read genome sequence data. Linkage disequilibrium between loci is accounted for by treating short-read sequences as noisy multilocus emissions from an underlying model of haplotype evolution. A hierarchical model-selection procedure is used to infer the underlying fitness landscape of the virus insofar as that landscape is explored by the viral population. In a first application of our method, we analyze data from an evolutionary experiment describing the growth of a reassortant H5N1 virus in ferrets. Across two sets of replica experiments we infer multiple alleles to be under selection, including variants associated with receptor binding specificity, glycosylation, and with the increased transmissibility of the virus. We identify epistasis as an important component of the within-host fitness landscape, and show that adaptation can proceed through multiple genetic pathways.

Biosecurity and Open-Source Biology: The Promise and Peril of Distributed Synthetic Biological Technologies

In this article, we raise ethical concerns about the potential misuse of open-source biology (OSB): biological research and development that progresses through an organisational model of radical openness, deskilling, and innovation. We compare this organisational structure to that of the open-source software model, and detail salient ethical implications of this model. We demonstrate that OSB, in virtue of its commitment to openness, may be resistant to governance attempts.

Dual-use decision making: relational and positional issues

Debates about dual-use research often turn on the potential for scientific research to be used to benefit or harm humanity. This dual-use potential is conventionally understood as the product of the magnitude of the harms and benefits of dual-use research, multiplied by their likelihood. This account, however, neglects important social aspects of the use of science and technology. In this paper, I supplement existing conceptions of dual-use potential to account for the social context of dual-use research. This account incorporates relational and positional concerns that feature in the success or failure of dual-use. I then defend this account against foreseeable objections.

Gain-of-function experiments: time for a real debate

The debate on whether to allow experiments that increase the transmission and/or pathogenicity of potential pandemic pathogens has recently gained renewed attention, particularly as a result of studies on influenza viruses. Here, five experts discuss the benefits and risks associated with these gain-of-function experiments, and how the ongoing debate affects the scientific community and the general public.

According to the WHO, dual use research of concern (DURC) is “life sciences research that is intended for benefit, but which might easily be misapplied to do harm”. Recent studies, particularly those on influenza viruses, have led to renewed attention on DURC, as there is an ongoing debate over whether the benefits of gain-of-function (GOF) experiments that result in an increase in the transmission and/or pathogenicity of potential pandemic pathogens (PPPs) are outweighed by concerns over biosecurity and biosafety. In this Viewpoint article, proponents and opponents of GOF experiments discuss the benefits and risks associated with these studies, as well as the implications of the current debate for the scientific community and the general public, and suggest how the current discussion should move forward.

Improving pandemic influenza risk assessment

Assessing the pandemic risk posed by specific non-human influenza A viruses is an important goal in public health research. As influenza virus genome sequencing becomes cheaper, faster, and more readily available, the ability to predict pandemic potential from sequence data could transform pandemic influenza risk assessment capabilities. However, the complexities of the relationships between virus genotype and phenotype make such predictions extremely difficult. The integration of experimental work, computational tool development, and analysis of evolutionary pathways, together with refinements to influenza surveillance, has the potential to transform our ability to assess the risks posed to humans by non-human influenza viruses and lead to improved pandemic preparedness and response.

An avian H7N1 gain-of-function experiment of great concern

Inappropriately named gain-of-function influenza research seeks to confer airborne transmission on avian influenza A viruses that otherwise cause only dead-end infections in humans. A recent study has succeeded in doing this with a highly pathogenic ostrich H7N1 virus in a ferret model without loss of virulence. If transposable to humans, this would constitute a novel virus with a case fatality rate ~30 greater than that of Spanish flu. A commentary from three distinguished virologists considered the benefits of this work to outweigh potential risks. I beg to disagree with conclusions in both papers, for the underlying science is not as strong as it appears.

Why has Not There been More Research of Concern?

Amid the renewed concern in the last several years about the potential for life science research to facilitate the spread of disease, a central plank of the policy response has been to enact processes for assessing the risks and benefits of "research of concern." The recent controversy regarding a proposed redaction of work on the modification of a H5N1 avian influenza virus is perhaps the most prominent such instance. And yet, a noteworthy feature of this case is its exceptionalness. In the last 10 years, life science publishers, funders, and labs have rarely identified any research as "of concern," let alone proposed censors. This article takes this experience with risk assessment as an invitation for reflection. Reasons for the low number of instances of concern are related to how the biosecurity dimensions of the life sciences are identified, how they are described, how the assessments of benefits and risks are undertaken, how value considerations do and do not enter into assessments, as well as the lack of information on the outcomes of reviews. This argument builds on such considerations to examine the limitations and implications of the risk-benefit experiment of concern framing, the politics of expertise as well as the prospects for alternative responses.