Influenza: One Health in action

The application of the One Health approach in the management of five major zoonotic diseases using the World Bank domains: A scoping review

The international authorities, such as the Food and Agriculture Organization of the United Nations, World Health Organization, World Organization for Animal Health, United Nations Environment Programme, and World Bank, have endorsed the One Health concept as an effective approach to optimize the health of people, animals, and the environment. The One Health concept is considered as an integrated and unifying approach with the objective of sustainably balancing and optimizing the health of people, animals, and ecosystems. Despite variations in its definitions, the underlying principle remains consistent - recognizing the interconnected and interdependent health of humans, animals, and the environment, necessitating interdisciplinary collaboration to optimize health outcomes. The One Health approach has been applied in numerous countries for detecting, managing, and controlling diseases. Moreover, the concept has found application in various areas, including antimicrobial resistance, food safety, and ecotoxicology, with a growing demand. There is a growing consensus that the One Health concept and the United Nations Sustainable Development Goals mutually reinforce each other. The World Bank has recommended five domains as foundational building blocks for operationalising the One Health approach, which includes: i) One Health stakeholders, roles, and responsibilities; ii) financial and personal resources; iii) communication and information; iv) technical infrastructure; and v) governance. The domains provide a generalised overview of the One Health concept and guide to its application. We conducted a scoping review following the five-staged Arksey and O'Malley's framework. The objective of the review was to map and synthesise available evidence of application of the One Health approach to five major zoonotic diseases using the World Bank domains. Publications from the year 2004, marking the inception of the term 'One Health,' to 2022 were included. Information was charted and categorised against the World Bank domains identified as a priori. We included 1132 records obtained from three databases: Embase, Medline, and Global Health; as well as other sources. After excluding duplicates, screening for titles and abstracts, and full text screening, 20 articles that contained descriptions of 29 studies that implemented the One Health approach were selected for the review. We found that included studies varied in the extent to which the five domains were utilised. Less than half the total studies (45%) used all the five domains and none of the studies used all the sub-domains. The environmental sector showed an underrepresentation in the application of the One Health approach to zoonotic diseases as 14 (48%) studies in 10 articles did not mention it as a stakeholder. Sixty two percent of the studies mentioned receiving support from international partners in implementing the One Health approach and 76% of the studies were supported by international donors to conduct the studies. The review identified disparate funding mechanisms employed in the implementation of the One Health approach. However, there were limited discussions on plans for continuity and viability of these funding mechanisms in the future.

Vaccination decreases the risk of influenza A virus reassortment but not genetic variation in pigs

Although vaccination is broadly used in North American swine breeding herds, managing swine influenza is challenging primarily due to the continuous evolution of influenza A virus (IAV) and the ability of the virus to transmit among vaccinated pigs. Studies that have simultaneously assessed the impact of vaccination on the emergence of IAV reassortment and genetic variation in pigs are limited. Here, we directly sequenced 28 bronchoalveolar lavage fluid (BALF) samples collected from vaccinated and unvaccinated pigs co-infected with H1N1 and H3N2 IAV strains, and characterized 202 individual viral plaques recovered from 13 BALF samples. We identified 54 reassortant viruses that were grouped in 17 single and 16 mixed genotypes. Notably, we found that prime-boost vaccinated pigs had less reassortant viruses than nonvaccinated pigs, likely due to a reduction in the number of days pigs were co-infected with both challenge viruses. However, direct sequencing from BALF samples revealed limited impact of vaccination on viral variant frequency, evolutionary rates, and nucleotide diversity in any IAV coding regions. Overall, our results highlight the value of IAV vaccination not only at limiting virus replication in pigs but also at protecting public health by restricting the generation of novel reassortants with zoonotic and/or pandemic potential.

Swine influenza A viruses cause severe illness among pigs and financial losses on pig farms worldwide. These viruses can also infect humans and have caused deadly human pandemics in the past. Influenza A viruses are dangerous because viruses can be transferred between humans, birds and pigs. These co-infections can allow the viruses to swap genetic material. Viral genetic exchanges can result in new virus strains that are more dangerous or that can infect other types of animals more easily.

Farmers vaccinate their pigs to control the swine influenza A virus. The vaccines are regularly updated to match circulating virus strains. But the virus evolves rapidly to escape vaccine-induced immunity, and infections are common even in vaccinated pigs. Learning about how vaccination affects the evolution of influenza A viruses in pigs could help scientists prevent outbreaks on pig farms and avoid spillover pandemics in humans.

Li et al. show that influenza A viruses are less likely to swap genetic material in vaccinated and boosted pigs than in unvaccinated animals. In the experiments, Li et al. collected swine influenza A samples from the lungs of pigs that had received different vaccination protocols. Next, Li et al. used next-generation sequencing to identify new mutations in the virus or genetic swaps among different strains. In pigs infected with both the H1N1 and H3N2 strains of influenza, the two viruses began trading genes within a week. But less genetic mixing occurred in vaccinated and boosted pigs because they spent less time infected with both viruses than in unvaccinated pigs. The vaccination status of the pig did not have much effect on how many new mutations occurred in the viruses.

The experiments show that vaccinating and boosting pigs against influenza A viruses may protect against genetic swapping among influenza viruses. If future studies on pig farms confirm the results, the information gleaned from the study could help scientists improve farm vaccine protocols to further reduce influenza risks to animals and people.

A universal RT-qPCR assay for "One Health" detection of influenza A viruses

The mutual dependence of human and animal health is central to the One Health initiative as an integrated strategy for infectious disease control and management. A crucial element of the One Health includes preparation and response to influenza A virus (IAV) threats at the human-animal interface. The IAVs are characterized by extensive genetic variability, they circulate among different hosts and can establish host-specific lineages. The four main hosts are: avian, swine, human and equine, with occasional transmission to other mammalian species. The host diversity is mirrored in the range of the RT-qPCR assays for IAV detection. Different assays are recommended by the responsible health authorities for generic IAV detection in birds, swine or humans. In order to unify IAV monitoring in different hosts and apply the One Health approach, we developed a single RT-qPCR assay for universal detection of all IAVs of all subtypes, species origin and global distribution. The assay design was centred on a highly conserved region of the IAV matrix protein (MP)-segment identified by a comprehensive analysis of 99,353 sequences. The reaction parameters were effectively optimised with efficiency of 93–97% and LOD_95% of approximately ten IAV templates per reaction. The assay showed high repeatability, reproducibility and robustness. The extensive in silico evaluation demonstrated high inclusivity, i.e. perfect sequence match in the primers and probe binding regions, established as 94.6% for swine, 98.2% for avian and 100% for human H3N2, pandemic H1N1, as well as other IAV strains, resulting in an overall predicted detection rate of 99% on the analysed dataset. The theoretical predictions were confirmed and extensively validated by collaboration between six veterinary or human diagnostic laboratories on a total of 1970 specimens, of which 1455 were clinical and included a diverse panel of IAV strains.

Informing influenza pandemic preparedness using commercial poultry farmer knowledge, attitudes, and practices (KAP) surrounding biosecurity and self-reported avian influenza outbreaks in Nepal

Avian influenza (AI) is a global health obstacle of critical concern as novel viruses are capable of initiating a pandemic. Recent spillover events of AI into human populations have occurred at human-poultry food system interfaces. As Nepal's poultry sector transitions to more intensified commercial production systems, it is important to examine the epidemiology of AI and the knowledge, attitudes and practices (KAP) of poultry sector workers. We conducted a cross-sectional KAP study utilizing a structured survey to interview 150 commercial poultry farmers in Chitwan District, Nepal. All commercial poultry farmers had knowledge of AI previous to the study and the majority farmers were able to identify farm-farm and poultry-human transmission mechanisms of AI. Farmers had more knowledge surrounding poultry AI symptoms as compared to human AI symptoms. Most farmers believe that AI is serious, contagious and a threat to everyone, yet only half believe it can be prevented. Individual-level personal protective equipment (PPE) uptake, such as facemask, glove and boot usage, on the enrolled farms was low and farm-level biosecurity practices varied greatly. Nine commercial poultry farms (6%) self-reported having an HPAI outbreak and 60 farms (40%) self-reported having an LPAI outbreak in the past 5 years. Layer farms had higher odds (OR: 5.4, 95% CI: 2.3–12.8) of self-reported LPAI as compared broiler farms. Poultry sector farmers face multiple obstacles when attempting to report AI to government authorities such as the fear of flock culling and the perceived lack of monetary compensation for culling. Our study provides updated KAP surrounding AI of farmers and self-reported AI farm-level epidemiology in Nepal's highest density commercial poultry production district. Commercial poultry farmers are fairly knowledgeable on AI, but do not take further protective practice efforts to implement their knowledge and prevent AI. Due to the potential role that human-poultry interfaces may play in AI emergence, it is critical to collaborate with the commercial poultry industry when planning and conducting AI pandemic preparedness mechanisms.

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Farmers had more knowledge surrounding poultry avian influenza symptoms as compared to human avian influenza symptoms.

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Farmer personal protective equipment (PPE) uptake, such as facemask, glove and boot usage, was low.

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6% of poultry farms self-reported having an HPAI outbreak and 40% self-reported having an LPAI outbreak in the past 5 years.

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Layer farms had higher odds of self-reported LPAI as compared broiler farms.

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Poultry farmers fear potential flock culling and lack of monetary compensation for culling when reporting avian influenza.

Subtype Diversity of Influenza A Virus in North American Waterfowl: a Multidecade Study

The discovery in 1976 of waterfowl as the primary reservoir of influenza A viruses (IAVs) has since spurred decades of waterfowl surveillance efforts by researchers dedicated to understanding the ecology of IAV and its subsequent threat to human and animal health. Here, we employed a multidecade, continental-scale approach of surveillance data to understand trends of seasonal IAV subtype diversity. Between 1976 and 2015, IAVs were detected in 8,427 (10.8%) of 77,969 samples from migratory waterfowl throughout the Central and Mississippi Migratory Flyways in the United States and Canada. A total of 96 hemagglutinin (HA)/neuraminidase (NA) subtype combinations were isolated, which included most HA (H1 to H14) and all 9 NA subtypes. We observed an annual trend of high influenza prevalence, involving a few dominant subtypes, on northern breeding grounds during summer with progressively lowered influenza prevalence, comprised of a highly diverse profile of subtypes, as waterfowl migrate toward southern wintering grounds. Isolates recovered during winter had the highest proportion of mixed and rare HA/NA combinations, indicating increased opportunity for reassortment of IAVs. In addition, 70% of H5 and 49% of H7 IAV isolates were recovered from samples collected during fall and spring, respectively; these are subtypes that can have significant implications for public health and agriculture sectors. Annual cyclical dominance of subtypes on northern breeding grounds is revealed through the longitudinal nature of this study. Our novel findings exhibit the unrealized potential for discovery using existing IAV surveillance data.IMPORTANCE Wild aquatic birds are the primary natural reservoir of influenza A viruses (IAVs) and are therefore responsible for the dispersal and maintenance of IAVs representing a broad range of antigenic and genetic diversity. The aims of IAV surveillance in waterfowl not only relate to understanding the risk of spillover risk to humans, but also to improving our understanding of basic questions related to IAV evolution and ecology. By evaluating several decades of surveillance data from wild aquatic birds sampled along North American migratory flyways, we discovered an annual trend of increasing subtype diversity during southbound migration, peaking on southern wintering grounds. Winter sampling revealed the highest proportion of mixed and rare infections that suggest higher opportunity for spillover. These findings allow improvements to surveillance efforts to robustly capture IAV diversity that will be used for vaccine development and cultivate a more thorough understanding of IAV evolution and persistence mechanisms.

Factors that enable effective One Health collaborations - A scoping review of the literature

Advocates for a One Health approach recognize that global health challenges require multidisciplinary collaborative efforts. While past publications have looked at interdisciplinary competency training for collaboration, few have identified the factors and conditions that enable operational One Health. Through a scoping review of the literature, a multidisciplinary team of researchers analyzed peer-reviewed publications describing multisectoral collaborations around infectious disease-related health events. The review identified 12 factors that support successful One Health collaborations and a coordinated response to health events across three levels: two individual factors (education & training and prior experience & existing relationships), four organizational factors (organizational structures, culture, human resources and, communication), and six network factors (network structures, relationships, leadership, management, available & accessible resources, political environment). The researchers also identified the stage of collaboration during which these factors were most critical, further organizing into starting condition or process-based factors. The research found that publications on multisectoral collaboration for health events do not uniformly report on successes or challenges of collaboration and rarely identify outputs or outcomes of the collaborative process. This paper proposes a common language and framework to enable more uniform reporting, implementation, and evaluation of future One Health collaborations.

Is there really such a thing as "one health"? Thinking about a more than human world from the perspective of cultural anthropology

Today's era of globalization is characterized by intensified interspecies encounters, growing ecological concerns and the (re-)emergence of infectious diseases, manifesting themselves in the interplay of medical and biological, but also social, cultural and political processes. One health approaches – which combine multidisciplinary efforts to stimulate collaborations between different health professionals such as veterinarians, medical practitioners, biologists, and public health professionals – can be understood as a response to this complex interconnectedness. Integrating a social science perspective might prove beneficial to this endeavor. This essay locates the one health discussion on disease ecologies in a more than human world within recent developments in cultural and medical anthropology that focus on the entanglements between health and a multitude of animals, plants or microbes, as they are characteristic of a globalized modernity. The paper aims to examine the social dimensions of human–animal-disease-interactions, claiming that disease is a biocultural phenomenon and that social factors generally play a crucial role in the emergence, spread and management of (infectious) disease. Consequently, it will be argued that there is a need to rethink our objects of inquiry and any given assumptions of human health, the human body or the constitution of “the global” as such. Incorporating the social sciences into one health approaches can help address topics such as consumption patterns, human–animal behavior or environmental conflicts in a novel way and on a grander scale than ever before. Yet, a greater sensitivity to context may entail some skepticism about the idea of one health – not in spite of the complex entanglements between humans, environments, animals and pathogens, but precisely because of them.

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Microbial globalization processes are neither unidirectional nor homogenous.

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Human and microbial social worlds are mutually correlated.

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Infectious diseases are a product of both, biological and social relations.

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Anthropological studies might help to situate and contextualize this interaction.

Promoting translational research in human and veterinary medical virology

Translational research serves as a bench-to-field "translation" of basic scientific research into practical diagnostic procedures and therapies useful in human and veterinary clinical services. The productivity of translational research involving infectious diseases relevant to both human and animal health (e.g., influenza diagnosis and epidemiology using emerging molecular detection and identification methods) can be maximized when both human and veterinary medical virology disciplines are integrated. Influenza viruses are continually evolving through site-specific mutation and segment reassortment, and these processes occur in all potential carrier species - including birds, humans, and many agriculturally important animals. This evolutionary plasticity occasionally allows "novel" influenzas to move from animal hosts to humans, potentially causing destructive pandemics; therefore, a rapid laboratory technique that can detect and identify "novel" influenza viruses is clinically and epidemiologically desirable. A technique-focused translational research approach is pursued to enhance detection and characterization of emerging influenza viruses circulating in both humans and other animal hosts. The PLEX-ID System, which incorporates multi-locus PCR and electrospray ionization/mass spectrometry, uses deliberately nonspecific primers that amplify all known variants (all H/N subtypes) of influenza virus, including human, other mammalian, and avian influenzas, and is therefore likely to generate analyzable amplicons from any novel influenza that might emerge in any host. Novel technology development and implementation such as the PLEX-ID System forms a key component of human and veterinary medical virology translational research.