Is Pollution the Primary Driver of Infectious Syndemics?

Syndemics, the adverse interaction of two or more coterminous diseases or other negative health conditions, have probably existed since human settlement, plant and animal domestication, urbanization, and the growth of social inequality beginning about 10-12,000 years ago. These dramatic changes in human social evolution significantly increased opportunities for the spread of zoonotic infectious diseases in denser human communities with increased sanitation challenges. In light of a growing body of research that indicates that anthropogenic air pollution causes numerous threats to health and is taking a far greater toll on human life and wellbeing than had been reported, this paper proposes the possibility that air pollution is now the primary driver of infectious disease syndemics. In support of this assertion, this paper reviews the growth and health impacts of air pollution, the relationship of air pollution to the development and spread of infectious diseases, and reported cases of air pollution-driven infectious disease syndemics, and presents public health recommendations for leveraging the biosocial insight of syndemic theory in responding to infectious disease.

Conceptualizing COVID-19 syndemics: A scoping review.

Background: COVID-19's heavy toll on human health, and its concentration within specific at-risk groups including the socially vulnerable and individuals with comorbidities, has made it the focus of much syndemic discourse. Syndemic theory recognizes that social factors create the conditions that support the clustering of diseases and that these diseases interact in a manner that worsens health outcomes. Syndemics theory has helped to facilitate systems-level approaches to disease as a biosocial phenomenon and guide prevention and treatment efforts. Despite its recognized value, reviews of syndemics literature have noted frequent misuse of the concept limiting its potential in guiding appropriate interventions. Objective: To review how the term 'syndemic' is defined and applied within peer-reviewed literature in relation to COVID-19. Design: A scoping review of definitions within COVID-19 literature published between January 1, 2020 to May 15, 2023 was conducted. Searches took place across six databases: Academic Search Premier, CINAHL, JSTOR, MEDLINE/Pubmed, PsycINFO and Scopus. PRISMA-ScR guidelines were followed. Results: Content analysis revealed that COVID-19 has varied clustered configurations of communicable-non-communicable diseases and novel communicable disease interactions. Spatial analysis was presented as a new strategy to evidence syndemic arrangements. However, syndemics continue to be regarded as universal, with continued misunderstanding and misapplication of the concept. Conclusion: This review found that current applications of syndemics remain problematic. Recommendations are made on the design of syndemic studies. A syndemic framework offers an opportunity for systems-level thinking that considers the full complexity of human-disease interactions and is useful to inform future pandemic preparations and responses.

Are There Global Syndemics?

In this article, we address the nature of syndemics and whether, as some have asserted, these epidemiological phenomena are global configurations. Our argument that syndemics are not global rests on recognition that they are composed of social/environment contexts, disease clusters, demographics, and biologies that vary across locations. These points are illustrated with the cases of syndemics involving COVID-19, diabetes mellitus, and HIV/AIDS. We draw on theoretical discourse from epidemiology, biology, and anthropology to present what we believe is a more accurate framework for thinking about syndemics with shared elements.

Deadly Companions: COVID-19 and Diabetes in Mexico.

In this commentary, I assess the adverse syndemic interactions between COVID-19 and diabetes mellitus. This syndemic is of major concern for a country like Mexico which has seen a steady rise in the percentage of its population suffering these diseases. Mexico now has one of the highest rates of diabetes in the world and a rapidly growing COVID-19 caseload.

In the shadow of HIV & TB: A commentary on the COVID epidemic in South Africa.

While COVID-19 has become a global pandemic that has spread to all regions of the globe, local historic, health, and socio-environmental factors shape the epidemiological contours, response, and social challenges present within each affected nation. Thus, while countries like China, Italy, Iran, Brazil, and the United States have all been hard hit by the pandemic, there are critical differences across these nations in a number of variables (e.g. demographic features, health histories, healthcare systems, infection case rates, case fatality rates, national responses). In other words, within the global pandemic there are multiple importantly distinct national epidemics. Overcoming the grave threats to public health presented by COVID-19 requires both international cooperation and country-specific efforts that reflect local histories, needs, and resources. Already concerns are being expressed among health officials about how COVID-19 might be devastating in Africa. Currently, South Africa has the highest number of diagnosed COVID-19 cases on the continent and has been identified as being at high risk in the pandemic. This paper examines the public health response to the COVID-19 threat, how the prior and ongoing HIV and TB epidemics shape the COVID-19 epidemic and influence the response, and the potential ramifications of the response.

What constitutes a syndemic? Methods, contexts, and framing from 2019.

PURPOSE OF REVIEW: The purpose of this review is to describe what methods were used for 60 articles on HIV syndemics in 2019, where they took place, what syndemic clusters emerged, and why this matters. RECENT FINDINGS: Most articles published in 2019 used regression analyses, and fewer used higher level modeling techniques, frequencies and descriptive, longitudinal cohort study, and social network analysis. Some employed ethnography, qualitative interviews, or were simply reviews. Most syndemic co-factors were substance abuse, risky sexual behavior, depression, intimate partner violence, stigma, sexually transmitted infections, and trauma and non-communicable diseases. Half of the studies were conducted in the United States and mostly in urban areas. Other contexts were Canada, Kenya, Uganda, Liberia, Nigeria, South Africa, and Botswana, Jamaica, Dominican Republic, India, Indonesia, China, Peru, and Romania. SUMMARY: Most recommendations suggested that people living with HIV need interventions that address other factors situated within their life, such as their mental health, social stigma, experiences of trauma and intimate partner violence, and social stigma and sexual risk taking. Many took an intersectoral approach and emphasized the need to consider the various factors that shape experiences with HIV, from sex, sexuality, class, race and ethnicity, and past trauma.

Whither syndemics?: Trends in syndemics research, a review 2015-2019.

As originally conceived, syndemics refers to complex epidemics involving two types of adverse interaction - the clustering and interactions of two or more diseases or health conditions (the biological-biological interface) and social environmental factors (the biological-social interface). The theory has been widely applied in the fields of medicine, public health and anthropology, but how the concept is conceptualised and investigated in new syndemics literature remains unclear. This paper offers a scoping review of recent syndemics literature aiming to address the question: Where have scholars taken the syndemics concept? Five bibliographic databases were searched for titles containing 'syndemic[s]' revealing 334 records. A total of 143 journal articles, 23 book chapters, 21 commentaries, 2 books and 5 dissertations were assessed. Citations were classified into five categories: syndemics (n = 22), potential syndemics (n = 34), socially determined heightened burden of disease (n = 29), harmful disease cluster (n = 32) and additive adverse conditions (n = 71). The limited number of citations meeting the definition of a syndemic arrangement highlights the challenges related to describing and empirically supporting the biological-biological and biological-social relationships. Nevertheless, there is value in retaining the original, holistic, biosocial meaning of syndemics to identify and detail the casual pathways and mechanisms of interactions.

Syndemics and the biosocial conception of health.

The syndemics model of health focuses on the biosocial complex, which consists of interacting, co-present, or sequential diseases and the social and environmental factors that promote and enhance the negative effects of disease interaction. This emergent approach to health conception and clinical practice reconfigures conventional historical understanding of diseases as distinct entities in nature, separate from other diseases and independent of the social contexts in which they are found. Rather, all of these factors tend to interact synergistically in various and consequential ways, having a substantial impact on the health of individuals and whole populations. Specifically, a syndemics approach examines why certain diseases cluster (ie, multiple diseases affecting individuals and groups); the pathways through which they interact biologically in individuals and within populations, and thereby multiply their overall disease burden, and the ways in which social environments, especially conditions of social inequality and injustice, contribute to disease clustering and interaction as well as to vulnerability. In this Series, the contributions of the syndemics approach for understanding both interacting chronic diseases in social context, and the implications of a syndemics orientation to the issue of health rights, are examined.

The spread of Zika and the potential for global arbovirus syndemics.

It is estimated that over a million people die each year from infectious diseases of zoonotic origin and hundreds of millions suffer from these pervasive threats to human well-being. In light of the emergent global concern over the Zika virus, evidence that it has not one but two competent mosquito vector species in the Aedes family, and that both can be co-infected with other pathogens including dengue and chikungunya, this paper examines research suggesting the prospect of significant twenty-first-century outbreaks of arbovirus syndemics. Uniting the concepts 'synergy' with 'epidemic', a syndemics approach recognises that diseases in a population occur neither independent of social and ecological conditions, nor in isolation from other diseases. Assessment of the potential for arbovirus syndemics entails a review of the human role in the global spread of Aedes mosquitoes, the socio-environmental conditions of Aedes diffusion, the increasing likelihood of co-transmission of arbovirus diseases, evidence of co-infection and concern about the adverse health effects of arbovirus syndemic interaction, and the need for an appropriate environment-sensitive framework for effective public health responses. Called Planetary Health, this emergent framework confronts conceptual, knowledge, and governance challenges created by the dramatic shifts in environments, climates, people, vectors, and pathogens in the world.

"I Feel Suffocated:" Understandings of Climate Change in an Inner City Heat Island.

Global climate change is contributing to a range of adverse environmental and weather shifts, including more intense and more frequent heatwaves and an intensification of the urban heat island effect. These changes are known to produce a set of significant and differentially distributed health problems, with a particularly high burden among poor and marginalized populations. In this article, we report findings from a qualitative study of community knowledge, attitudes, health and other concerns, and behavioral responses regarding mounting urban temperatures and related environmental health issues among Latinos living in the city of Hartford, CT in northeast United States. Findings suggest the need for enhanced participation in knowledge dissemination and preparedness planning based on the coproduction of knowledge about climate change and community responses to it. The special role of anthropology in such efforts is highlighted.

Ectoparasitic Syndemics: Polymicrobial Tick-borne Disease Interactions in a Changing Anthropogenic Landscape.

Based on an assessment of the available research, this article uses syndemic theory to suggest the role of adverse bio-social interactions in increasing the total disease burden of tick-borne infections in local populations. Given the worldwide distribution of ticks, capacity for coinfection, the anthropogenic role in environmental changes that facilitate tick dissemination and contact, evidence of syndemic interaction in tick-borne diseases, and growing impact of ticks on global health, tick-borne syndemics reveal fundamental ways in which human beings are not simply agents of environmental change but objects of that change as well.

Individuals Are Continents; or, Why It's Time to Retire the Island Approach to Addiction.

Individuals are not island isolates. This is an old insight that finds expression in indigenous worldviews, ancient philosophies, religious doctrine, and modern social theories. Even so, science remains encumbered by the false dichotomies and reductionism inherited from the capitalist revolution and reinforced by the fragmentation of modern life. This same heritage encumbers addiction research and efforts to devise effective interventions. It does so because the island concept at its core filters out the most decisive factors contributing to addiction. We therefore recommend its replacement with what we call the continental concept of the individual, which conceives of society and the natural environment as extensions of individual corporeal bodies. Such a theoretical reorientation has significant implications for intervention research and practice. More specifically, it radically expands the scope of what constitutes a valid intervention in the first place. We call this reorientation the continental approach to drug addiction.

Factors associated with hepatitis B vaccine series completion in a randomized trial for injection drug users reached through syringe exchange programs in three US cities.

BACKGROUND: Hepatitis B virus (HBV) is a vaccine preventable infection yet vaccination rates are low among injection drug users (IDUs) despite the high risk of infection and longstanding recommendations to promote vaccination. We sought to improve vaccination rates by reaching IDUs through syringe exchange programs (SEPs) in three U.S. cities. METHODS: IDUs were randomized in a trial comparing the standard HBV vaccination schedule (0, 1, and 6 months) to an accelerated schedule (0, 1, and 2 months) and participation data were analyzed to identify determinants of completion of the three-dose vaccine series. Independent variables explored included sociodemographics, injection and syringe access behaviors, assessment of health beliefs, HBV-associated knowledge, and personal health status. RESULTS: Covariates associated with completion of the three-dose vaccine series were accelerated vaccine schedule (aOR 1.92, 95% CI 1.34, 2.58, p = <0.001), older age (aOR 1.05, 95% CI 1.03, 1.07, p = <0.001), and poorer self-rated health score (aOR 1.26, 95% CI 1.05, 1.5, p = 0.02). Completion was less likely for those getting syringes from SEP customers than for SEP customers (OR 0.33, 95% CI 0.19, 0.58, p = <0.001). CONCLUSIONS: SEPs should offer hepatitis vaccination in a manner that minimizes time between first and last visits by accelerating the dosing schedule. Public health interventions should target younger, less healthy, and non-SEP customer participants. Other health interventions at SEPs may benefit from similar approaches that reach out beyond regular SEP customers.

The syndemics of childhood diarrhoea: a biosocial perspective on efforts to combat global inequities in diarrhoea-related morbidity and mortality.

Diarrhoea remains the second leading cause of death in children under 5 years. Moreover, morbidity as a result of diarrhoea is high particularly in marginalised communities. Frequent bouts of diarrhoea have deleterious and irreversible effects on physical and cognitive development. Children are especially vulnerable given their inability to mount an active immune response to pathogen exposure. Biological limitations are exacerbated by the long-term effects of poverty, including reduced nutrition, poor hygiene and deprived home environments. Drawing from available literature, this paper uses syndemic theory to explore the role of adverse biosocial interactions in increasing the total disease burden of enteric infections in low-resources populations and assesses the limitations of recent global calls to action. The syndemic perspective describes situations in which adverse social conditions, including inequality, poverty and other forms of political and economic oppression, play a critical role in facilitating disease-disease interactions. Given the complex micro- and macro-nature of childhood diarrhoea, including interactions between pathogens, disease conditions and social environments, the syndemic perspective offers a way forward. While rarely the focus of health interventions, technologically advanced biomedical strategies are likely to be more effective if coupled with interventions that address the social conditions of disparity.

Development, coinfection, and the syndemics of pregnancy in Sub-Saharan Africa.

Notable among gaps in the achievement of the global health Millennium Development Goals (MDG) are shortcomings in addressing maternal health, an issue addressed in the fifth MDG. This shortfall is particularly acute in Sub-Saharan Africa (SSA), where over half of all maternal deaths occur each year. While there is not as yet a comprehensive understanding of the biological and social causes of maternal death in SSA, it is evident that poverty, gendered economic marginalization, social disruptions, hindered access to care, unevenness in the quality of care, illegal and clandestine abortions, and infections are all critical factors. Beyond these factors, this paper presents a review of the existing literature on maternal health in SSA to argue that syndemics constitute a significant additional source of maternal morbidity and mortality in the region. Increasing focus on the nature, prevention, and treatment of syndemics, as a result, should be part and parcel of improving maternal health in SSA.

The social context and meaning of virginity loss among African American and Puerto Rican young adults in Hartford.

We describe virginity loss experiences of inner-city minority youth to understand the meaning attributed to first sex and the social and structural factors that contribute to early sexual debut. We interviewed 62 18-25-year-old African American and Puerto Rican Hartford men and women about their sexual and romantic life histories. Transcripts were coded in ATLAS.ti and analyzed for themes about virginity and sexual debut. We found different conceptions of virginity as a stigma to be lost, a normal part of growing up, and a gift to be given. The normative experience was consensual, early, and unplanned sexual debut. Inner-city minority youth have similar feelings, motivations, and experiences of sexual debut as non-ethnic youth reported in the literature except they are far younger. We discuss structural factors that affect inner-city sexual scripts for early sexual debut and identify it as a health inequity.

Criminalization of HIV transmission and exposure: research and policy agenda.

More than half of US jurisdictions have laws criminalizing knowing exposure to or transmission of HIV, yet little evidence supports these laws' effectiveness in reducing HIV incidence. These laws may undermine prevention efforts outlined in the US National HIV/AIDS Strategy, in which the United States has invested substantial federal funds. Future research should include studies of (1) the impact of US HIV exposure laws on public health systems and practices; (2) enforcement of these laws, including arrests, prosecutions, convictions, and sentencing; (3) alternatives to HIV exposure laws; and (4) direct and opportunity costs of enforcement. Policy efforts to mitigate potential negative impacts of these laws could include developing prosecutorial guidelines, modernized statutes, and model public health policies and protocols.