Adjusting the focus: A public health ethics approach to data research

This paper contends that a research ethics approach to the regulation of health data research is unhelpful in the era of population‐level research and big data because it results in a primary focus on consent (meta‐, broad, dynamic and/or specific consent). Two recent guidelines – the 2016 WMA Declaration of Taipei on ethical considerations regarding health databases and biobanks and the revised CIOMS International ethical guidelines for health‐related research involving humans – both focus on the growing reliance on health data for research. But as research ethics documents, they remain (to varying degrees) focused on consent and individual control of data use. Many current and future uses of health data make individual consent impractical, if not impossible. Many of the risks of secondary data use apply to communities and stakeholders rather than individual data subjects. Shifting from a research ethics perspective to a public health lens brings a different set of issues into view: how are the benefits and burdens of data use distributed, how can data research empower communities, who has legitimate decision‐making capacity? I propose that a public health ethics framework – based on public benefit, proportionality, equity, trust and accountability – provides more appropriate tools for assessing the ethical uses of health data. The main advantage of a public health approach for data research is that it is more likely to foster debate about power, justice and equity and to highlight the complexity of deciding when data use is in the public interest.     

耐药菌在人-动物-环境中的传播和遗传机制

我国细菌耐药现象十分普遍,多重耐药甚至泛耐药的菌株不断出现,给公共卫生和食品安全造成了重大威胁。随着人类活动以及农业畜牧业的发展,在物理和生物作用力之下,医疗行业和养殖业对环境产生了很大的负面影响,导致养殖动物及其相关环境中存在大量的耐药基因/耐药细菌。医疗行业、动物养殖、自然环境三者在耐药菌的传播和发展中是相互影响、互相作用的有机整体,耐药基因可以借助基因水平转移等方式在人、动物和环境中循环传播,增加了人类摄入耐药基因的风险。面对此类公共卫生问题,传统单一化的卫生工作系统已很难有效地解决这类挑战,急需多学科、多领域的合作来共同应对。文中对我国临床、动物和环境中的细菌耐药现状以及耐药菌在其中的传播和遗传机制进行了综述,以期为细菌耐药研究提供参考。     

Ethical Issues in Field Trials of Genetically Modified Disease‐Resistant Mosquitoes

Mosquito‐borne diseases take a tremendous toll on human populations, especially in developing nations. In the last decade, scientists have developed mosquitoes that have been genetically modified to prevent transmission of mosquito‐borne diseases, and field trials have been conducted. Some mosquitoes have been rendered infertile, some have been equipped with a vaccine they transmit to humans, and some have been designed to resist diseases. This article focuses on ethical issues raised by field trials of disease‐resistant, genetically modified mosquitoes. Some of these issues include: protecting the public and the environment from harm, balancing benefits and risks, collaborating with the local community, avoiding exploitation, and safeguarding the rights and welfare of research subjects. One of the most difficult problems involves protecting the welfare of community members who will be impacted by the release of mosquitoes but who are not enrolled in the study as research subjects. To address this concern, field trials should take place only when the targeted disease is a significant public health problem in an isolated area, the benefits of the trial for the community are likely to outweigh the risks, community leaders approve of the trial, and there are measures in place to protect the welfare of un‐enrolled community members, such as informing the community about the study and offering free treatment to people who contract mosquito‐borne diseases. Since the justification of any field trial depends on a careful examination of the scientific and ethical issues, proposed studies should be evaluated on a case‐by‐case basis.     

A Metapopulation Model to Assess the Capacity of Spread of Meticillin-Resistant Staphylococcus aureus ST398 in Humans

The emergence of the livestock-associated clone of meticillin-resistant Staphylococcus aureus (MRSA) ST398 is a serious public health issue throughout Europe. In The Netherlands a stringent ‘search-and-destroy’ policy has been adopted, keeping low the level of MRSA prevalence. However, reports have recently emerged of transmission events between humans showing no links to livestock, contradicting belief that MRSA ST398 is poorly transmissible in humans. The question regarding the transmissibility of MRSA ST398 in humans therefore remains of great interest. Here, we investigated the capacity of MRSA ST398 to spread into an entirely susceptible human population subject to the effect of a single MRSA-positive commercial pig farm. Using a stochastic, discrete-time metapopulation model, we explored the effect of varying both the probability of persistent carriage and that of acquiring MRSA due to contact with pigs on the transmission dynamics of MRSA ST398 in humans. In particular, we assessed the value and key determinants of the basic reproduction ratio (R ₀) for MRSA ST398. Simulations showed that the presence of recurrent exposures with pigs in risky populations allows MRSA ST398 to persist in the metapopulation and transmission events to occur beyond the farming community, even when the probability of persistent carriage is low. We further showed that persistent carriage should occur in less than 10% of the time for MRSA ST398 to conserve epidemiological characteristics similar to what has been previously reported. These results indicate that implementing control policy that only targets human carriers may not be sufficient to control MRSA ST398 in the community if it remains in pigs. We argue that farm-level control measures should be implemented if an eradication programme is to be considered.     

VIM‐1 carbapenemase‐producing Escherichia coli in gulls from southern France

Acquired carbapenemases currently pose one of the most worrying public health threats related to antimicrobial resistance. A NDM‐1‐producing Salmonella Corvallis was reported in 2013 in a wild raptor. Further research was needed to understand the role of wild birds in the transmission of bacteria resistant to carbapenems. Our aim was to investigate the presence of carbapenem‐resistant Escherichia coli in gulls from southern France. In 2012, we collected 158 cloacal swabs samples from two gull species: yellow‐legged gulls (Larus michahellis) that live in close contact with humans and slender‐billed gulls (Chroicocephalus genei) that feed at sea. We molecularly compared the carbapenem‐resistant bacteria we isolated through culture on selective media with the carbapenem‐susceptible strains sampled from both gull species and from stool samples of humans hospitalized in the study area. The genes coding for carbapenemases were tested by multiplex PCR. We isolated 22 carbapenem‐resistant E. coli strains from yellow‐legged gulls while none were isolated from slender‐billed gulls. All carbapenem‐resistant isolates were positive for bla_VIM‐1 gene. VIM‐1‐producing E. coli were closely related to carbapenem‐susceptible strains isolated from the two gull species but also to human strains. Our results are alarming enough to make it urgently necessary to determine the contamination source of the bacteria we identified. More generally, our work highlights the need to develop more bridges between studies focusing on wildlife and humans in order to improve our knowledge of resistant bacteria transmission routes.     

On being the right size: the impact of population size and stochastic effects on the evolution of drug resistance in hospitals and the community

The evolution of drug resistant bacteria is a severe public health problem, both in hospitals and in the community. Currently, some countries aim at concentrating highly specialized services in large hospitals in order to improve patient outcomes. Emergent resistant strains often originate in health care facilities, but it is unknown to what extent hospital size affects resistance evolution and the resulting spillover of hospital-associated pathogens to the community. We used two published datasets from the US and Ireland to investigate the effects of hospital size and controlled for several confounders such as antimicrobial usage, sampling frequency, mortality, disinfection and length of stay. The proportion of patients acquiring both sensitive and resistant infections in a hospital strongly correlated with hospital size. Moreover, we observe the same pattern for both the percentage of resistant infections and the increase of hospital-acquired infections over time. One interpretation of this pattern is that chance effects in small hospitals impede the spread of drug-resistance. To investigate to what extent the size distribution of hospitals can directly affect the prevalence of antibiotic resistance, we use a stochastic epidemiological model describing the spread of drug resistance in a hospital setting as well as the interaction between one or several hospitals and the community. We show that the level of drug resistance typically increases with population size: In small hospitals chance effects cause large fluctuations in pathogen population size or even extinctions, both of which impede the acquisition and spread of drug resistance. Finally, we show that indirect transmission via environmental reservoirs can reduce the effect of hospital size because the slow turnover in the environment can prevent extinction of resistant strains. This implies that reducing environmental transmission is especially important in small hospitals, because such a reduction not only reduces overall transmission but might also facilitate the extinction of resistant strains. Overall, our study shows that the distribution of hospital sizes is a crucial factor for the spread of drug resistance.     

Prioritising Healthcare Workers for Ebola Treatment: Treating Those at Greatest Risk to Confer Greatest Benefit

The Ebola epidemic in Western Africa has highlighted issues related to weak health systems, the politics of drug and vaccine development and the need for transparent and ethical criteria for use of scarce local and global resources during public health emergency. In this paper we explore two key themes. First, we argue that independent of any use of experimental drugs or vaccine interventions, simultaneous implementation of proven public health principles, community engagement and culturally sensitive communication are critical as these measures represent the most cost‐effective and fair utilization of available resources. Second, we attempt to clarify the ethical issues related to use of scarce experimental drugs or vaccines and explore in detail the most critical ethical question related to Ebola drug or vaccine distribution in the current outbreak: who among those infected or at risk should be prioritized to receive any new experimental drugs or vaccines? We conclude that healthcare workers should be prioritised for these experimental interventions, for a variety of reasons.     

Asymptomatic Clostridium difficile Colonisation and Onward Transmission

Introduction

Combined genotyping/whole genome sequencing and epidemiological data suggest that in endemic settings only a minority of Clostridium difficile infection, CDI, is acquired from other cases. Asymptomatic patients are a potential source for many unexplained cases.

Methods

We prospectively screened a cohort of medical inpatients in a UK teaching hospital for asymptomatic C. difficile carriage using stool culture. Electronic and questionnaire data were used to determine risk factors for asymptomatic carriage by logistic regression. Carriage isolates were compared with all hospital/community CDI cases from the same geographic region, from 12 months before the study to 3 months after, using whole genome sequencing and hospital admission data, assessing particularly for evidence of onward transmission from asymptomatic cases.

Results

Of 227 participants recruited, 132 provided ≥1 stool samples for testing. 18 participants were culture-positive for C. difficile, 14/132(11%) on their first sample. Independent risk factors for asymptomatic carriage were patient reported loose/frequent stool (but not meeting CDI criteria of ≥3 unformed stools in 24 hours), previous overnight hospital stay within 6 months, and steroid/immunosuppressant medication in the last 6 months (all p≤0.02). Surprisingly antibiotic exposure in the last 6 months was independently associated with decreased risk of carriage (p = 0.005). The same risk factors were identified excluding participants reporting frequent/loose stool. 13/18(72%) asymptomatically colonised patients carried toxigenic strains from common disease-causing lineages found in cases. Several plausible transmission events to asymptomatic carriers were identified, but in this relatively small study no clear evidence of onward transmission from an asymptomatic case was seen.

Conclusions

Transmission events from any one asymptomatic carrier are likely to be relatively rare, but as asymptomatic carriage is common, it may still be an important source of CDI, which could be quantified in larger studies. Risk factors established for asymptomatic carriage may help identify patients for inclusion in such studies.     

A Reservoir of Drug-Resistant Pathogenic Bacteria in Asymptomatic Hosts

The population genetics of pathogenic bacteria has been intensively studied in order to understand the spread of disease and the evolution of virulence and drug resistance. However, much less attention has been paid to bacterial carriage populations, which inhabit hosts without producing disease. Since new virulent strains that cause disease can be recruited from the carriage population of bacteria, our understanding of infectious disease is seriously incomplete without knowledge on the population structure of pathogenic bacteria living in an asymptomatic host. We report the first extensive survey of the abundance and diversity of a human pathogen in asymptomatic animal hosts. We have found that asymptomatic swine from livestock productions frequently carry populations of Salmonella enterica with a broad range of drug-resistant strains and genetic diversity greatly exceeding that previously described. This study shows how agricultural practice and human intervention may lead and influence the evolution of a hidden reservoir of pathogens, with important implications for human health.     

Public transport as a reservoir of methicillin‐resistant staphylococci

Aims: The aim of this study was to explore the occurrence of methicillin‐resistant staphylococci in a large urban public transport system. Methods and Results: Samples were taken from hand rails, which passengers hold onto when they are standing. In total, 1400 swabs taken from 55 vehicles (trolleybuses, trams and buses) were examined. As many as 30·1% samples were positive for the presence of methicillin‐resistant coagulase‐negative staphylococci (MRCoNS), but none for methicillin‐resistant Staphylococcus aureus (MRSA). MRCoNS were isolated from all 55 vehicles. Nearly 50% of MRCoNS isolates displayed resistance not only to beta‐lactams, but at least to two or more other classes of antimicrobials as well. Conclusions: This study demonstrated widespread occurrence of MRCoNS on hand rails in public transport vehicles. MRSA was not detected. Significance and Impact of the Study: The recovery of methicillin‐resistant staphylococci from public transport system implies a potential risk for transmission of these bacteria in an out‐hospital environment.     

The prevalence of antimicrobial‐resistant Escherichia coli in sympatric wild rodents varies by season and host

Aims: To investigate the prevalence and temporal patterns of antimicrobial resistance in wild rodents with no apparent exposure to antimicrobials. Methods and Results: Two sympatric populations of bank voles and wood mice were trapped and individually monitored over a 2‐ year period for faecal carriage of antimicrobial‐resistant Escherichia coli. High prevalences of ampicillin‐, chloramphenicol‐, tetracycline‐ and trimethoprim‐resistant E. coli were observed. A markedly higher prevalence of antimicrobial‐resistant E. coli was found in wood mice than in bank voles, with the prevalence in both increasing over time. Superimposed on this trend was a seasonal cycle with a peak prevalence of resistant E. coli in mice in early‐ to mid‐summer and in voles in late summer and early autumn. Conclusions: These sympatric rodent species had no obvious contact with antimicrobials, and the difference in resistance profiles between rodent species and seasons suggests that factors present in their environment are unlikely to be drivers of such resistance. Significance and Impact of the Study: These findings suggest that rodents may represent a reservoir of antimicrobial‐resistant bacteria, transmissible to livestock and man. Furthermore, such findings have implications for human and veterinary medicine regarding antimicrobial usage and subsequent selection of antimicrobial‐resistant organisms.     

Ethical issues surrounding controlled human infection challenge studies in endemic low-and middle-income countries

Controlled human infection challenge studies (CHIs) involve intentionally exposing research participants to, and/or thereby infecting them with, micro-organisms. There have been increased calls for more CHIs to be conducted in low- and middle-income countries (LMICs) where many relevant diseases are endemic. This article is based on a research project that identified and analyzed ethical and regulatory issues related to endemic LMIC CHIs via (a) a review of relevant literature and (b) qualitative interviews involving 45 scientists and ethicists with relevant expertise. In this article we argue that though there is an especially strong case for conducting CHIs in endemic (LMIC) settings, certain ethical issues related to the design and conduct of such studies (in such settings) nonetheless warrant particularly careful attention. We focus on ethical implications of endemic LMIC CHIs regarding (a) potential direct benefits for participants, (b) risks to participants, (c) third-party risks, (d) informed consent, (e) payment of participants, and (f) community engagement. We conclude that there is a strong ethical rationale to conduct (well-designed) CHIs in endemic LMICs, that certain ethical issues warrant particularly careful consideration, and that ethical analyses of endemic LMIC CHIs can inform current debates in research ethics more broadly.     

Application of Ethical Principles to Research using Public Health Data in The Global South: Perspectives from Africa

Existing ethics guidelines, influential literature and policies on ethical research generally focus on real‐time data collection from humans. They enforce individual rights and liberties, thereby lowering need for aggregate protections. Although dependable, emerging public health research paradigms like research using public health data (RUPD) raise new challenges to their application. Unlike traditional research, RUPD is population‐based, aligned to public health activities, and often reliant on pre‐collected longitudinal data. These characteristics, when considered in relation to the generally lower protective ethico‐legal frameworks of the Global South, including Africa, highlight ethical gaps. Health and demographic surveillance systems are examples of public health programs that accommodate RUPD in these contexts. We set out to explore the perspectives of professionals with a working knowledge of these systems to determine practical ways of appropriating the foundational principles of health research to advance the ever growing opportunities in RUPD. We present their perspectives and in relation to the literature and our ethical analysis, make context relevant recommendations. We further argue for the development of a framework founded on the discussions and recommendations as a minimum base for achieving optimal ethics for optimal RUPD in the Global South.     

‘To be,or not to be’—The dilemma of ‘silent’ antimicrobial resistance genes in bacteria

Antimicrobial resistance is a serious threat to public health that dramatically undermines our ability to treat bacterial infections. Microorganisms exhibit resistance to different drug classes by acquiring resistance determinants through multiple mechanisms including horizontal gene transfer. The presence of drug resistance genotypes is mostly associated with corresponding phenotypic resistance against the particular antibiotic. However, bacterial communities harbouring silent antimicrobial resistance genes—genes whose presence is not associated with a corresponding resistant phenotype do exist. Under suitable conditions, the expression pattern of such genes often revert and regain resistance and could potentially lead to therapeutic failure. We often miss the presence of silent genes, since the current experimental paradigms are focused on resistant strains. Therefore, the knowledge on the prevalence, importance and mechanism of silent antibiotic resistance genes in bacterial pathogens are very limited. Silent genes, therefore, provide an additional level of complexity in the war against drug-resistant bacteria, reminding us that not only phenotypically resistant strains but also susceptible strains should be carefully investigated. In this review, we discuss the presence of silent antimicrobial resistance genes in bacteria, their relevance and their importance in public health.     

Mandatory HIV antibody testing policies: an ethical analysis

Widespread mandatory testing for the human immunodeficiency virus (HIV) has been proposed by some as a way to curb the transmission of the virus. O'Brien examines the possible uses and limits of HIV testing to determine in what instances the potential public health benefits of testing outweigh its burdens and limitations. She subjects proposals for mandatory testing of three populations -- hospital patients, surgery patients, and prisoners -- to ethical analysis, and then formulates ethical guidelines for rational and morally defensible HIV antibody testing policies in hospital and prison settings.     

Evaluating the risks of public health programs: Rational antibiotic use and antimicrobial resistance

Existing ethical frameworks for public health provide insufficient guidance on how to evaluate the risks of public health programs that compromise the best clinical interests of present patients for the benefit of others. Given the relevant similarity of such programs to clinical research, we suggest that insights from the long‐standing debate about acceptable risk in clinical research can helpfully inform and guide the evaluation of risks posed by public health programs that compromise patients’ best clinical interests. We discuss how lessons learned regarding the ethics of risk in one context can be fruitfully transferred to the other, using the example of a so‐called ‘rational antibiotic use’ guideline that limits antimicrobial prescribing in order to curb antimicrobial resistance.     

Collection, use, and protection of population-based birth defects surveillance data in the united states

Birth defects surveillance systems collect population-based birth defects data from multiple sources to track trends in prevalence, identify risk factors, refer affected families to services, and evaluate prevention efforts. Strong state and federal public health and legal mandates are in place to govern the collection and use of these data. Despite the prima facie appeal of "opt-in" and similar strategies to those who view data collection as a threat to privacy, the use of these strategies in lieu of population-based surveillance can severely limit the ability of public health agencies to accurately access the health status of a group within a defined geographical area. With the need for population-based data central to their mission, birth defects programs around the country take their data stewardship role seriously, recognizing both moral and legal obligations to protect the data by employing numerous safeguards. Birth defects surveillance systems are shaped by the needs of the community they are designed to serve, with the goal of preventing birth defects or alleviating the burdens associated with them.     

Ethics and drug resistance

This paper reviews the dynamics behind, and ethical issues associated with, the phenomenon of drug resistance. Drug resistance is an important ethical issue partly because of the severe consequences likely to result from the increase in drug resistant pathogens if more is not done to control them. Drug resistance is also an ethical issue because, rather than being a mere quirk of nature, the problem is largely a product of drug distribution. Drug resistance results from the over-consumption of antibiotics by the wealthy; and it, ironically, results from the under-consumption of antibiotics, usually by the poor or otherwise marginalized. In both kinds of cases the phenomenon of drug resistance illustrates why health (care)--at least in the context of infectious disease--should be treated as a (global) public good. The point is that drug resistance involves 'externalities' affecting third parties. When one patient develops a resistant strain of disease because of her over- or under-consumption of medication, this more dangerous malady poses increased risk to others. The propriety of free-market distribution of goods subject to externalities is famously dubious--given that the 'efficiency' rationale behind markets assumes an absence of externalities. Market failure in the context of drug resistance is partly revealed by the fact that no new classes of antibiotics have been developed since 1970. I conclude by arguing that the case of drug resistance reveals additional reasons--to those traditionally appealed to by bioethicists--for treating health care as something special when making policy decisions about its distribution.     

Aggressive Chemotherapy and the Selection of Drug Resistant Pathogens

Drug resistant pathogens are one of the key public health challenges of the 21^st century. There is a widespread belief that resistance is best managed by using drugs to rapidly eliminate target pathogens from patients so as to minimize the probability that pathogens acquire resistance de novo. Yet strong drug pressure imposes intense selection in favor of resistance through alleviation of competition with wild-type populations. Aggressive chemotherapy thus generates opposing evolutionary forces which together determine the rate of drug resistance emergence. Identifying treatment regimens which best retard resistance evolution while maximizing health gains and minimizing disease transmission requires empirical analysis of resistance evolution in vivo in conjunction with measures of clinical outcomes and infectiousness. Using rodent malaria in laboratory mice, we found that less aggressive chemotherapeutic regimens substantially reduced the probability of onward transmission of resistance (by >150-fold), without compromising health outcomes. Our experiments suggest that there may be cases where resistance evolution can be managed more effectively with treatment regimens other than those which reduce pathogen burdens as fast as possible.