Application of Multi-Criteria Decision Analysis Techniques for Informing Select Agent Designation and Decision Making

Future Issues in Global Health: Challenges and Conundrums

This perspective lays out the challenges and conundrums facing global health and discusses possible solutions applicable in the future. The world is facing numerous challenges that include those associated with globalization, climate change, emerging diseases, continuation of non-communicable diseases, reemerging communicable diseases, antimicrobial resistance (AMR), wars, terrorism, and humanitarian crises, among others. The recent challenges exaggerated by the COVID-19 pandemic have exposed vulnerabilities within healthcare systems, particularly in low- and middle-income countries (LMIC). The solutions must be interprofessional and multifarious with collaborative efforts and partnerships. One world order seems to be a far-fetched ideal utopian goal, but it can be a remedy for ensuring health for all. In the meantime, strengthening the World Health Organization's role in coordinating global health efforts and improving its capacity to respond to future health crises will be critical in ensuring that the vision of a unified, healthier world becomes a reality.

Monkeypox: A Viral Zoonotic Disease of Rising Global Concern

Monkeypox (mpox) is a rare viral zoonotic disease, endemic to Central and West Africa, caused by the monkeypox virus, an orthopoxvirus similar to the variola virus (smallpox). Although sporadic travel-associated cases have historically occurred outside Africa, in May 2022, mpox began spreading globally in multiple nonendemic countries across several continents. In 2024, there has been an increase in globally reported confirmed cases of mpox and deaths from mpox, making it a public health emergency of international concern. The reasons for the unusual global spread are under investigation but likely relate to increased travel and waning population immunity to orthopoxviruses. Transmission now appears to be mainly through close, intimate contact, especially among men who have sex with men. Mpox is usually a self-limited disease. Although limited approved antiviral treatments are available, such as tecovirimat, which the European Medicines Agency approved in January 2022 for the treatment of mpox, their widespread availability and effectiveness in the current outbreak remain to be investigated. Public health control measures include surveillance, case identification/isolation, contact tracing, and targeted vaccination of contacts at high risk of exposure. However, challenges remain in curtailing the current unprecedented outbreak. Critical knowledge gaps include animal reservoir(s) responsible for initial spillover events, viral mutations that may enhance transmissibility, optimal diagnostics for noninvasive specimens, effective antiviral therapies, next-generation vaccines providing longer-term immunity, and building global capacity for outbreak response. This review summarizes the current literature on mpox virology, epidemiology, pathogenesis, clinical manifestations, diagnostics, treatment, prevention, and public health control measures. Ongoing investigation and research are needed to better understand mpox’s evolving epidemiology, pathogenicity, transmissibility, and ecology to guide strategies for containing the outbreak and preventing future global emergence.

Fungal diversity in the soil Mycobiome: Implications for ONE health

Today, over 300 million individuals worldwide are afflicted by severe fungal infections, many of whom will perish. Fungi, as a result of their plastic genomes have the ability to adapt to new environments and extreme conditions as a consequence of globalization, including urbanization, agricultural intensification, and, notably, climate change. Soils and the impact of these anthropogenic environmental factors can be the source of pathogenic and non-pathogenic fungi and subsequent fungal threats to public health. This underscores the growing understanding that not only is fungal diversity in the soil mycobiome a critical component of a functioning ecosystem, but also that soil microbial communities can significantly contribute to plant, animal, and human health, as underscored by the One Health concept. Collectively, this stresses the importance of investigating the soil microbiome in order to gain a deeper understanding of soil fungal ecology and its interplay with the rhizosphere microbiome, which carries significant implications for human health, animal health and environmental health.

A simple undergraduate laboratory exercise for teaching the role of sentinel-level clinical microbiology testing in biological threat identification

Undergraduate students in the biomedical sciences are mostly unaware of how clinical microbiology laboratories handle suspected agents of bioterrorism or emerging infectious diseases. The Public Health Security Bioterrorism Preparedness and Response Act of 2002 requires the US Department of Health and Human Services (HHS) to maintain a list of microbes that pose serious biological threats to human health and safety, including Tier 1 agents with the potential for use in bioterrorism. The Laboratory Response Network (LRN), founded by the Centers for Disease Control and Prevention, the Federal Bureau of Investigation, and the Association of Public Health Laboratories, coordinates the response of sentinel, reference, and national laboratories to these biothreats. The sentinel laboratories, which comprise most hospital-based and commercial laboratories, are the first to encounter a suspicious agent. For this reason, the LRN has published a series of testing guidelines to assist the sentinel laboratories in deciding whether a microbial isolate should be considered potentially hazardous and thus sent to a reference or national laboratory for further characterization. Here, we describe a simple laboratory exercise that teaches sentinel-level testing requirements in the context of an applied setting of a potential outbreak of anthrax that would require a sentinel laboratory to recognize a potential threat, attempt to rule it out, and refer to a national laboratory for identification.

Application of multi-criteria decision analysis techniques and decision support framework for informing plant select agent designation and decision making

The United States Department of Agriculture (USDA) Division of Agricultural Select Agents and Toxins (DASAT) established a list of biological agents (Select Agents List) that threaten crops of economic importance to the United States and regulates the procedures governing containment, incident response, and the security of entities working with them. Every 2 years the USDA DASAT reviews their select agent list, utilizing assessments by subject matter experts (SMEs) to rank the agents. We explored the applicability of multi-criteria decision analysis (MCDA) techniques and a decision support framework (DSF) to support the USDA DASAT biennial review process. The evaluation includes both current and non-select agents to provide a robust assessment. We initially conducted a literature review of 16 pathogens against 9 criteria for assessing plant health and bioterrorism risk and documented the findings to support this analysis. Technical review of published data and associated scoring recommendations by pathogen-specific SMEs was found to be critical for ensuring accuracy. Scoring criteria were adopted to ensure consistency. The MCDA supported the expectation that select agents would rank high on the relative risk scale when considering the agricultural consequences of a bioterrorism attack; however, application of analytical thresholds as a basis for designating select agents led to some exceptions to current designations. A second analytical approach used agent-specific data to designate key criteria in a DSF logic tree format to identify pathogens of low concern that can be ruled out for further consideration as select agents. Both the MCDA and DSF approaches arrived at similar conclusions, suggesting the value of employing the two analytical approaches to add robustness for decision making.

Regulating Select Agent Chimeras: Defining the Problem(s) Through the Lens of SARS-CoV-1/SARS-CoV-2 Chimeric Viruses

In late 2021, the US Centers for Disease Control and Prevention (CDC) posted an interim final rule (86 FR 64075) to the federal register regulating the possession, use, and transfer of SARS-CoV-1/SARS-CoV-2 chimeric viruses. In doing so, the CDC provided the reasoning that viral chimeras combining the transmissibility of SARS-CoV-2 with the pathogenicity and lethality of SARS-CoV-1 pose a significant risk to public health and should thus be placed on the select agents and toxins list. However, 86 FR 64075 lacked clarity in its definitions and scope, some of which the CDC addressed in response to public comments in the final rule, 88 FR 13322, in early 2023. To evaluate these regulatory actions, we reviewed the existing select agent regulations to understand the landscape of chimeric virus regulation. Based on our findings, we first present clear definitions for the terms "chimeric virus," "viral chimera," and "virulence factor" and provide a list of SARS-CoV-1 virulence factors in an effort to aid researchers and federal rulemaking for these agents moving forward. We then provide suggestions for a combination of similarity and functional characteristic cutoffs that the government could use to enable researchers to distinguish between regulated and nonregulated chimeras. Finally, we discuss current select agent regulations and their overlaps with 86 FR 64075 and 88 FR 13322 and make suggestions for how to address chimera concerns within and/or without these regulations. Collectively, we believe that our findings fill important gaps in current federal regulations and provide forward-looking philosophical and practical analysis that can guide future decisionmaking.

Chimeric Viruses Containing Select Agents: The Biology Behind Their Creation, Attenuation, and Exclusion From Regulation

The US Centers for Disease Control and Prevention (CDC), as part of the Federal Select Agent Program, and under the purview of 42 CFR §73.3, has the ability to regulate chimeric viruses that contain portions of pathogens that are part of the select agents and toxins list. In addition, the CDC is responsible for excluding pathogens from regulation, including chimeric viruses, that are sufficiently attenuated. Since 2003, the CDC has excluded over 20 chimeric viruses that contain portions of select agents. But in late 2021, the CDC proposed a regulatory first-the addition of a chimeric virus to the select agents and toxins list. To better understand the importance and applicability of this action, we surveyed the landscape of previous exclusions from select agent regulation. First, we reviewed the exclusion criteria used by the Intragovernmental Select Agents and Toxins Technical Advisory Committee in their advisement of the Federal Select Agent Program. We then reviewed the literature on chimeric viruses that contain portions of select agents and that have been excluded from regulation due to sufficient attenuation, focusing on chimeric alphaviruses and chimeric avian influenza viruses. By analyzing biological commonalities and patterns in the structure and methodology of the development of previously excluded chimeric viruses, we provide insight into how the CDC has used exclusion criteria in the past to regulate chimeric viruses. We conclude by contrasting previous exclusions with the recent addition of SARS-CoV-1/SARS-CoV-2 chimeric viruses to the select agents and toxins list, demonstrating that this addition strays from established, effective regulatory processes, and is thus a regulatory misstep.

Application of multi-criteria decision analysis techniques and decision support framework for informing select agent designation for agricultural animal pathogens

The United States Department of Agriculture (USDA), Division of Agricultural Select Agents and Toxins (DASAT) established a list of biological agents and toxins (Select Agent List) that potentially threaten agricultural health and safety, the procedures governing the transfer of those agents, and training requirements for entities working with them. Every 2 years the USDA DASAT reviews the Select Agent List, using subject matter experts (SMEs) to perform an assessment and rank the agents. To assist the USDA DASAT biennial review process, we explored the applicability of multi-criteria decision analysis (MCDA) techniques and a Decision Support Framework (DSF) in a logic tree format to identify pathogens for consideration as select agents, applying the approach broadly to include non-select agents to evaluate its robustness and generality. We conducted a literature review of 41 pathogens against 21 criteria for assessing agricultural threat, economic impact, and bioterrorism risk and documented the findings to support this assessment. The most prominent data gaps were those for aerosol stability and animal infectious dose by inhalation and ingestion routes. Technical review of published data and associated scoring recommendations by pathogen-specific SMEs was found to be critical for accuracy, particularly for pathogens with very few known cases, or where proxy data (e.g., from animal models or similar organisms) were used to address data gaps. The MCDA analysis supported the intuitive sense that select agents should rank high on the relative risk scale when considering agricultural health consequences of a bioterrorism attack. However, comparing select agents with non-select agents indicated that there was not a clean break in scores to suggest thresholds for designating select agents, requiring subject matter expertise collectively to establish which analytical results were in good agreement to support the intended purpose in designating select agents. The DSF utilized a logic tree approach to identify pathogens that are of sufficiently low concern that they can be ruled out from consideration as a select agent. In contrast to the MCDA approach, the DSF rules out a pathogen if it fails to meet even one criteria threshold. Both the MCDA and DSF approaches arrived at similar conclusions, suggesting the value of employing the two analytical approaches to add robustness for decision making.

The development and use of decision support framework for informing selection of select agent toxins with modelling studies to inform permissible toxin amounts

Many countries have worked diligently to establish and implement policies and processes to regulate high consequence pathogens and toxins that could have a significant public health impact if misused. In the United States, the Antiterrorism and Effective Death Penalty Act of 1996 (Public Law 104-132, 1996), as amended by the Bioterrorism Preparedness and Response Act of 2002 (Public Law 107-188, 2002) requires that the Department of Health and Human Services (HHS) [through the Centers for Disease Control and Prevention (CDC)] establish a list of bacteria, viruses, and toxins that have the potential to pose a severe threat to public health and safety. Currently, this list is reviewed and updated on a biennial basis using input from subject matter experts (SMEs). We have developed decision support framework (DSF) approaches to facilitate selection of select toxins and, where toxicity data are known, conducted modelling studies to inform selection of toxin amounts that should be excluded from select agent regulations. Exclusion limits allow laboratories to possess toxins under an established limit to support their research or teaching activities without the requirement to register with the Federal Select Agent Program. Fact sheets capturing data from a previously vetted SME workshop convened by CDC, literature review and SME input were developed to assist in evaluating toxins using the DSF approach. The output of the DSF analysis agrees with the current select toxin designations, and no other toxins evaluated in this study were recommended for inclusion on the select agent and toxin list. To inform the selection of exclusion limits, attack scenarios were developed to estimate the amount of toxin needed to impact public health. Scenarios consisted of simulated aerosol releases of a toxin in high-population-density public facilities and the introduction of a toxin into a daily consumable product supply chain. Using published inhalation and ingestion median toxic dose (TD₅₀) and median lethal dose (LD₅₀) values, where available, a range of toxin amounts was examined to estimate the number of people exposed to these amounts in these scenarios. Based on data generated by these models, we proposed toxin exclusion values corresponding to levels below those that would trigger a significant public health response (i.e., amounts estimated to expose up to ten people by inhalation or one hundred people by ingestion to LD₅₀ or TD₅₀ levels of toxin in the modeled scenarios).