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Individuals with diminished social connections are at higher risk of mental disorders, dementia, circulatory conditions and musculoskeletal conditions. However, evidence is limited by a disease-specific focus and no systematic examination of sex differences or the role of pre-existing mental disorders.
Methods
We conducted a cohort study using data on social disconnectedness (loneliness, social isolation, low social support and a composite measure) from the 2013 and 2017 Danish National Health Survey linked with register data on 11 broad categories of medical conditions through 2021. Poisson regression was applied to estimate incidence rate ratios (IRRs), incidence rate differences (IRDs), and explore sex differences and interaction with pre-existing mental disorders.
Results
Among 162,497 survey participants, 7.6%, 3.5% and 14.8% were classified as lonely, socially isolated and with low social support, respectively. Individuals who were lonely and with low social support had a higher incidence rate in all 11 categories of medical conditions (interquartile range [IQR] of IRRs, respectively 1.26–1.49 and 1.10–1.14), whereas this was the case in nine categories among individuals who were socially isolated (IQR of IRRs, 1.01–1.31). Applying the composite measure, the highest IRR was 2.63 for a mental disorder (95% confidence interval [CI], 2.38–2.91), corresponding to an IRD of 54 (95% CI, 47–61) cases per 10,000 person-years. We found sex and age differences in some relative and absolute estimates, but no substantial deviations from additive interaction with pre-existing mental disorders.
Conclusions
This study advances our knowledge of the risk of medical conditions faced by individuals who are socially disconnected. In addition to the existing evidence, we found higher incidence rates for a broad range of medical condition categories. Contrary to previous evidence, our findings suggest that loneliness is a stronger determinant for subsequent medical conditions than social isolation and low social support.
A preregistered analysis plan and statistical code are available at Open Science Framework (https://osf.io/pycrq).
Rather than leading to the emergence of a problem, some processes contribute to limiting their scope and impeding agenda-setting. These “nonproblems” are situations that could have led to social mobilizations or public intervention but end up neither being publicized nor subject to strong policy. We use occupational health in France to illustrate these mechanisms. The social invisibility of work-related ill-health is linked to the joint contribution of two processes. Firstly, from the perspective of research on ignorance and undone science, scientific knowledge is under-developed compared to other public health issues. And even available knowledge is rarely used by policy-makers. Secondly, policies use underestimated numbers from the occupational diseases compensation system. This specific configuration of knowledge/ignorance and official counting plays a central role in the production of occupational health issues as a nonproblem. Their invisibility contributes to the production of inertia and public inaction that characterize public policy in this field.
In 2020, COVID-19 modeling studies predicted rapid epidemic growth and quickly overwhelmed health systems in humanitarian and fragile settings due to preexisting vulnerabilities and limited resources. Despite the growing evidence from Bangladesh, no study has examined the epidemiology of COVID-19 in out-of-camp settings in Cox’s Bazar during the first year of the pandemic (March 2020-March 2021). This paper aims to fill this gap.
Methods
Secondary data analyses were conducted on case and testing data from the World Health Organization and the national health information system via the District Health Information Software 2.
Results
COVID-19 in Cox’s Bazar was characterized by a large peak in June 2020, followed by a smaller wave in August/September and a new wave from March 2021. Males were more likely to be tested than females (68% vs. 32%, P < 0.001) and had higher incidence rates (305.29/100 000 males vs. 114.90/100 000 female, P < 0.001). Mortality was significantly associated with age (OR: 87.3; 95% CI: 21.03-350.16, P < 0.001) but not sex. Disparities existed in testing and incidence rates among upazilas.
Conclusions
Incidence was lower than expected, with indicators comparable to national-level data. These findings are likely influenced by the younger population age, high isolation rates, and low testing capacity. With testing extremely limited, true incidence and mortality rates are likely higher, highlighting the importance of improving disease surveillance in fragile settings. Data incompleteness and fragmentation were the main study limitations.
Contemporary data relating to antipsychotic prescribing in UK primary care for patients diagnosed with severe mental illness (SMI) are lacking.
Aims
To describe contemporary patterns of antipsychotic prescribing in UK primary care for patients diagnosed with SMI.
Method
Cohort study of patients with an SMI diagnosis (i.e. schizophrenia, bipolar disorder, other non-organic psychoses) first recorded in primary care between 2000 and 2017 derived from Clinical Practice Research Datalink. Patients were considered exposed to antipsychotics if prescribed at least one antipsychotic in primary care between 2000 and 2019. We compared characteristics of patients prescribed and not prescribed antipsychotics; calculated annual prevalence rates for antipsychotic prescribing; and computed average daily antipsychotic doses stratified by patient characteristics.
Results
Of 309 378 patients first diagnosed with an SMI in primary care between 2000 and 2017, 212,618 (68.7%) were prescribed an antipsychotic between 2000 and 2019. Antipsychotic prescribing prevalence was 426 (95% CI, 420–433) per 1000 patients in the year 2000, reaching a peak of 550 (547–553) in 2016, decreasing to 470 (468–473) in 2019. The proportion prescribed antipsychotics was higher among patients diagnosed with schizophrenia (81.0%) than with bipolar disorder (64.6%) and other non-organic psychoses (65.7%). Olanzapine, quetiapine, risperidone and aripiprazole accounted for 78.8% of all antipsychotic prescriptions. Higher mean olanzapine equivalent total daily doses were prescribed to patients with the following characteristics: schizophrenia diagnosis, ethnic minority status, male gender, younger age and greater relative deprivation.
Conclusions
Antipsychotic prescribing is dominated by olanzapine, quetiapine, risperidone and aripiprazole. We identified potential disparities in both the receipt and prescribed doses of antipsychotics across subgroups. To inform efforts to optimise prescribing and ensure equity of care, further research is needed to understand why certain groups are prescribed higher doses and are more likely to be treated with long-acting injectable antipsychotics compared with others.
Migraine and post-traumatic stress disorder (PTSD) are both twice as common in women as men. Cross-sectional studies have shown associations between migraine and several psychiatric conditions, including PTSD. PTSD is disproportionally common among patients in headache clinics, and individuals with migraine and PTSD report greater disability from migraines and more frequent medication use. To further clarify the nature of the relationship between PTSD and migraine, we conducted bidirectional analyses of the association between (1) migraine and incident PTSD and (2) PTSD and incident migraine.
Methods
We used longitudinal data from 1989–2020 among the 33,327 Nurses’ Health Study II respondents to the 2018 stress questionnaire. We used log-binomial models to estimate the relative risk of developing PTSD among women with migraine and the relative risk of developing migraine among individuals with PTSD, trauma-exposed individuals without PTSD, and individuals unexposed to trauma, adjusting for race, education, marital status, high blood pressure, high cholesterol, alcohol intake, smoking, and body mass index.
Results
Overall, 48% of respondents reported ever experiencing migraine, 82% reported experiencing trauma and 9% met the Diagnostic and Statistical Manual of Mental Disorders-5 criteria for PTSD. Of those reporting migraine and trauma, 67% reported trauma before migraine onset, 2% reported trauma and migraine onset in the same year and 31% reported trauma after migraine onset. We found that migraine was associated with incident PTSD (adjusted relative risk [RR]: 1.26, 95% confidence interval [CI]: 1.14–1.39). PTSD, but not trauma without PTSD, was associated with incident migraine (adjusted RR: 1.20, 95% CI: 1.14–1.27). Findings were consistently stronger in both directions among those experiencing migraine with aura.
Conclusions
Our study provides further evidence that migraine and PTSD are strongly comorbid and found associations of similar magnitude between migraine and incident PTSD and PTSD and incident migraine.
Commonly occurring mental health disorders have been well studied in terms of epidemiology, presentation, risk factors and management. However, rare or uncommon mental health disorders and events are harder to study. One way to do this is active surveillance. This article summarises how the Royal College of Psychiatrists Child and Adolescent Psychiatry Surveillance System was developed, as well as the key studies that have used the system and their impact, to make the case for a wider international surveillance unit for child and adolescent psychiatry. Keeping this surveillance active in different populations across the globe will add to existing knowledge and understanding of these uncommon disorders and events. This will in turn help in developing better frameworks for the identification and management for these disorders and events. It will also facilitate the sharing of ideas regarding current methodology, ethics, the most appropriate means of evaluating units and their potential applications.
Assessing the risk of subsequent self-harm after hospitalisation for COVID-19 is critical for mental health care planning during and after the pandemic.
Aims
This study aims to compare the risk of admission to hospital for self-harm within 12 months following a COVID-19 hospitalisation during the first half of 2020, with the risk following hospitalisations for other reasons.
Method
Using the French administrative healthcare database, logistic regression models were employed to analyse data from patients admitted to hospitals in metropolitan France between January and June 2020. The analysis included adjustments for sociodemographic factors, psychiatric history and the level of care received during the initial hospital stay.
Results
Of the 96 313 patients hospitalised for COVID-19, 336 (0.35%) were subsequently admitted for self-harm within 12 months, compared to 20 135 (0.72%) of 2 797 775 patients admitted for other reasons. This difference remained significant after adjusting for sociodemographic factors (adjusted odds ratio (aOR) = 0.66, 95% CI: 0.59–0.73), psychiatric disorder history (aOR = 0.65, 95% CI: 0.58–0.73) and the level of care received during the initial hospital stay (aOR = 0.70, 95% CI: 0.63–0.78). History of psychiatric disorders and intensive care were strongly correlated with increased risk, while older age was inversely associated with self-harm admissions.
Conclusions
Hospitalisation for COVID-19 during the early pandemic was linked to a lower risk of subsequent self-harm than hospitalisation for other reasons. Clinicians should consider psychiatric history and intensive care factors in evaluating the risk of future suicide.
Between February and April 2018, Salmonella typhimurium within a unique 5-single nucleotide polymorphism (SNP) address was isolated from 28 cases with links to a small rural area of Northeast England, with five cases prospectively identified by whole genome sequencing (WGS). Infections had a severe clinical picture with ten cases hospitalized (36%), two cases with invasive disease, and two deaths reported. Interviews determined that 24 cases (86%) had been exposed to a local independent butcher’s shop (Butcher A).
A case-control study using controls recruited by systematic digit dialling established that cases were 68 times more likely to have consumed cooked meat from Butcher A (Adjusted OR 68.1; 95% CI: 1.9–2387.6; P = 0.02). Salmonella typhimurium genetically highly related to 28 of the outbreak cases was also isolated from a sample of cooked meat on sale in the premises.
Epidemiological and microbiological investigations suggest this outbreak was likely associated with the consumption of ready-to-eat foods supplied by the implicated butcher. A relatively large number of cases were involved despite the rurality of the food business, with cases resident across the Northeast and Yorkshire identified using WGS, demonstrating the benefit of timely sequencing information to community outbreak investigations.
We investigated associations between ‘healthy dietary pattern’ scores, at ages 36, 43, 53 and 60-64 years, and body composition at age 60-64 among participants from the MRC National Survey of Health and Development (NSHD). Principal component analyses of dietary data (food diaries) at age 60-64 were used to calculate diet scores (healthy dietary pattern scores) at each age. Higher scores indicated healthier diets (higher consumption of fruit, vegetables and wholegrain bread). Linear regression was used to investigate associations between diet scores at each age and height-adjusted dual-energy x-ray absorptiometry-measured fat and lean mass measures at age 60-64. Analyses, adjusting for sex and other potential confounders (age, smoking history, physical activity and occupational class), were implemented among 692 men and women. At age 43, 53 and 60-64, higher diet scores were associated with lower fat mass index (FMI) and android: gynoid fat mass ratio; for example, in fully-adjusted analyses, a standard deviation (SD) increase in diet score at age 60-64 was associated with a difference in mean FMI of -0.18 SD (95% CI: -0.25, -0.10). In conditional analyses, higher diet scores at ages 43, 53 and 60-64 (than expected from diet scores at younger ages) were associated with lower FMI and android: gynoid fat mass ratio in fully-adjusted analyses. Diet scores at age 36 had weaker associations with the outcomes considered. No associations regarding appendicular lean mass index were robust after full adjustment. This suggests that improvements in diet through adulthood are linked to beneficial effects on adiposity in older age.
The COVID-19 pandemic has disproportionately affected women's mental health. However, most evidence has focused on mental illbeing outcomes, and there is little evidence on the mechanisms underlying this unequal impact.
Aims
To investigate gender differences in the long-term trajectories of life satisfaction, how these were affected during the pandemic and the role of time-use differences in explaining gender inequalities.
Method
We used data from 6766 (56.2% women) members of the 1970 British Cohort Study (BCS70). Life satisfaction was prospectively assessed between the ages of 26 (1996) and 51 (2021) years, using a single question with responses ranging from 0 (lowest) to 10 (highest). We analysed life satisfaction trajectories with piecewise latent growth curve models, and investigated whether gender differences in the change in the life satisfaction trajectories with the pandemic were explained by self-reported time spent doing different paid and unpaid activities.
Results
Women had consistently higher life satisfaction than men before the pandemic (Δintercept,unadjusted = 0.213, 95% CI 0.087–0.340; P = 0.001) and experienced a more accelerated decline with the pandemic onset (Δquad2,unadjusted = −0.018, 95% CI −0.026 to −0.011; P < 0.001). Time-use differences did not account for the more accelerated decrease in women's life satisfaction levels with the pandemic (Δquad2,adjusted = −0.016, 95% CI −0.031 to −0.001; P = 0.035).
Conclusions
Our study shows pronounced gender inequalities in the impact of the pandemic on the long-term life satisfaction trajectories of adults in their 50s, with women losing their pre-pandemic advantage over men. Self-reported time-use differences did not account for these inequalities. More research is needed to tackle gender inequalities in population mental health.
There is evidence that social contagion plays a role in shaping the clinical presentation of some psychiatric symptoms, particularly affecting features that vary over time and culture. Some symptoms can increase so rapidly in prevalence that they become ‘epidemic’. The mechanism involves a spread through peers and/or the media. Within broader domains of psychopathology, this process draws from a ‘symptom pool’ that can determine which specific symptoms will appear. This article illustrates these mechanisms by focusing on non-suicidal self-injury (NSSI), a syndrome that has been subject to social contagion and whose prevalence may have increased among adolescents.
Observational studies consistently report associations between tobacco use, cannabis use and mental illness. However, the extent to which this association reflects an increased risk of new-onset mental illness is unclear and may be biased by unmeasured confounding.
Methods
A systematic review and meta-analysis (CRD42021243903). Electronic databases were searched until November 2022. Longitudinal studies in general population samples assessing tobacco and/or cannabis use and reporting the association (e.g. risk ratio [RR]) with incident anxiety, mood, or psychotic disorders were included. Estimates were combined using random-effects meta-analyses. Bias was explored using a modified Newcastle–Ottawa Scale, confounder matrix, E-values, and Doi plots.
Results
Seventy-five studies were included. Tobacco use was associated with mood disorders (K = 43; RR: 1.39, 95% confidence interval [CI] 1.30–1.47), but not anxiety disorders (K = 7; RR: 1.21, 95% CI 0.87–1.68) and evidence for psychotic disorders was influenced by treatment of outliers (K = 4, RR: 3.45, 95% CI 2.63–4.53; K = 5, RR: 2.06, 95% CI 0.98–4.29). Cannabis use was associated with psychotic disorders (K = 4; RR: 3.19, 95% CI 2.07–4.90), but not mood (K = 7; RR: 1.31, 95% CI 0.92–1.86) or anxiety disorders (K = 7; RR: 1.10, 95% CI 0.99–1.22). Confounder matrices and E-values suggested potential overestimation of effects. Only 27% of studies were rated as high quality.
Conclusions
Both substances were associated with psychotic disorders and tobacco use was associated with mood disorders. There was no clear evidence of an association between cannabis use and mood or anxiety disorders. Limited high-quality studies underscore the need for future research using robust causal inference approaches (e.g. evidence triangulation).
It is widely recognized that the COVID-19 pandemic exerted an impact on the mental health of the general population, but epidemiological evidence is surprisingly sparse. We aimed to explore the association between serologically confirmed SARS-CoV-2 infection and psychological distress – assessed by symptoms of depression, anxiety and stress – in the general adult population in southern Switzerland, a region widely affected by the pandemic. We also investigated whether this association varied over time and between pandemic waves from late 2020 through 2021.
Methods
We used data from 305 adults who participated in the Corona Immunitas Ticino prospective seroprevalence study in southern Switzerland, including results of the serological tests of SARS-CoV-2 infection collected in June 2021, and explored associations with depression, anxiety and stress scores as measured by the 21-item Depression, Anxiety and Stress Scale at three time points between December 2020 and August 2021, accounting for socio-demographic and health characteristics.
Results
In our sample, 84.3% of the participants (mean age of 51.30 years, SD = ±.93) were seronegative at baseline. Seropositive (i.e., infected) participants had a decreasing probability of being depressed and anxious through the COVID-19 pandemic waves compared to the seronegative (non-infected) participants. Further, seropositivity at baseline was also associated with more rapid decline in depressive, anxiety and stress symptomatology, and younger age and the presence of chronic diseases were independently associated with mild anxiety (OR = .97; P = 0.013; 95% CI = 0.95, 0.99; OR = 3.47; P = 0.001; 95% CI = 1.71, 7.04) and stress (OR = .96; P = 0.003; 95% CI = .94, .99; OR = 2.56; P = 0.010; 95% CI = 1.25, 5.22).
Conclusions
Our results suggest that the MH consequences of the pandemic may not be due to the SARS-CoV-2 infection per se, but to fears associated with the risk of infection, and to the pandemic uncertainties.
Although natural hazards (e.g., tropical cyclones, earthquakes) disproportionately affect developing countries, most research on their mental health impact has been conducted in high-income countries. We aimed to summarize prevalences of mental disorders in Global South populations (classified according to the United Nations Human Development Index) affected by natural hazards.
Methods
To identify eligible studies for this meta-analysis, we searched MEDLINE, PsycINFO and Web of Science up to February 13, 2024, for observational studies with a cross-sectional or longitudinal design that reported on at least 100 adult survivors of natural hazards in a Global South population and assessed mental disorders with a validated instrument at least 1 month after onset of the hazard. Main outcomes were the short- and long-term prevalence estimates of mental disorders. The project was registered on the International Prospective Register of Systematic Reviews (CRD42023396622).
Results
We included 77 reports of 75 cross-sectional studies (six included a non-exposed control group) comprising 82,400 individuals. We found high prevalence estimates for post-traumatic stress disorder (PTSD) in the general population (26.0% [95% CI 18.5–36.3]; I2 = 99.0%) and depression (21.7% [95% CI 10.5–39.6]; I2 = 99.2%) during the first year following the event, with similar prevalences observed thereafter (i.e., 26.0% and 23.4%, respectively). Results were similar for regions with vs. without recent armed conflict. In displaced samples, the estimated prevalence for PTSD was 46.5% (95% CI 39.0–54.2; k = 6; I2 = 93.3). We furthermore found higher symptom severity in exposed, versus unexposed, individuals. Data on other disorders were scarce, apart from short-term prevalence estimates of generalised anxiety disorder (15.9% [95% CI 4.7–42.0]; I2 = 99.4).
Conclusions
Global South populations exposed to natural hazards report a substantial burden of mental disease. These findings require further attention and action in terms of implementation of mental health policies and low-threshold interventions in the Global South in the aftermath of natural hazards. However, to accurately quantify the true extent of this public health challenge, we need more rigorous, well-designed epidemiological studies across diverse regions. This will enable informed decision making and resource allocation for those in need.
Introduction: The elderly population presents aggravating factors for the risk of suicide that must be considered. In this sense, it is known that there is a tendency for elderly people not to reveal suicidal ideation and to make highly self-destructive attempts. Furthermore, poorly planned retirement, social isolation, death of a spouse, family and friends can make this situation worse. However, few studies address this topic and public policies regarding suicide among the elderly are still scarce.
Objectives: To analyze the prevalence of suicide among elderly people in different regions of Brazil between 2019 and 2021.
Methods: Quantitative, descriptive and exploratory, cross-sectional study. For collection, the DATASUS database was used, based on information regarding the cause of intentional self- harm codes X60 to X84, based on the 10th revision of the International Statistical Classification of Diseases and Related HealthProblems.
Results: It was observed that in Brazil, among elderly people of both sexes, the highest suicide rates are found in the age group of 60 to 69 years, with the general proportion of suicides being higher in the male population. Furthermore, the Southeast Region had the highest number of notifications, while the North Region of the country had the lowest. The age group equal to or greater than 80 years, presented the highest number of cases in the South Region.
Conclusions: Suicide notifications are an alarm for understanding the risk factors that must be carefully identified through a broader look at issues of mental health in the elderly. This information makes it possible to understand the current scenario of deaths by region to detect populations with a higher incidence and understand the binomial of mental health and aging.
Mass Casualty Incidents (MCIs) pose significant challenges to health care systems, especially regarding emergency preparedness and response. This study aims to analyze the epidemiological characteristics and burden of MCIs in Spain from 2014 to 2022, focusing on the type, frequency, and impact of these incidents on public health and emergency services.
Methods
A population-based retrospective observational study examined MCIs in Spain between January 2014 and December 2022. Data were collected from various emergency services. Incidents involving 4 or more victims requiring medical assistance and ambulance mobilization were included. The study categorized MCIs into 5 types: road traffic accidents, fires and explosions, chemical poisonings, maritime accidents, and others.
Results
A total of 1618 MCIs resulting in 8556 victims were identified, averaging 15 (95% CI, 11-19) incidents per month, with 79% due to road traffic accidents and 13% to fires and explosions, which also had the highest average of 7.6 victims per incident. Despite maritime accidents comprising only 1.9% of incidents, they had the highest fatality rate. MCIs were more frequent on weekends, in January and July, and between 3:00 PM and 9:00 PM. The average response time was 38 minutes, with 35% of victims sustaining severe injuries.
Conclusions
Despite a slight decrease in annual MCIs from 2014 to 2022 in Spain, the trend is not statistically significant. The study highlights the need for a national registry and standardized data collection to enhance emergency preparedness and response planning and facilitate the reduction of the MCI burden.
Foodborne diseases are ongoing and significant public health concerns. This study analysed data obtained from the Foodborne Outbreaks Surveillance System of Wenzhou to comprehensively summarise the characteristics of foodborne outbreaks from 2012 to 2022. A total of 198 outbreaks were reported, resulting in 2,216 cases, 208 hospitalisations, and eight deaths over 11 years. The findings suggested that foodborne outbreaks were more prevalent in the third quarter, with most cases occurring in households (30.8%). Outbreaks were primarily associated with aquatic products (17.7%) as sources of contamination. The primary transmission pathways were accidental ingestion (20.2%) and multi-pathway transmission (12.1%). Microbiological aetiologies (46.0%), including Vibrio parahaemolyticus, Salmonella ssp., and Staphylococcus aureus, were identified as the main causes of foodborne outbreaks. Furthermore, mushroom toxins (75.0%), poisonous animals (12.5%), and poisonous plants (12.5%) were responsible for deaths from accidental ingestion. This study identified crucial settings and aetiologies that require the attention of both individuals and governments, thereby enabling the development of effective preventive measures to mitigate foodborne outbreaks, particularly in coastal cities.
Confounding refers to a mixing or muddling of effects that can occur when the relationship we are interested in is confused by the effect of something else. It arises when the groups we are comparing are not completely exchangeable and so differ with respect to factors other than their exposure status. If one (or more) of these other factors is a cause of both the exposure and the outcome, then some or all of an observed association between the exposure and outcome may be due to that factor.
In this chapter, we look at the analytic studies that are our main tools for identifying the causes of disease and evaluating health interventions. Unlike descriptive epidemiology, analytic studies involve planned comparisons between people with and without disease, or between people with and without exposures thought to cause (or prevent) disease. They try to answer the questions, ‘Why do some people develop disease?’ and ‘How strong is the association between exposure and outcome?’. This group of studies includes the intervention, cohort and case–control studies that you met briefly in Chapter 1. Together, descriptive and analytic epidemiology provide information for all stages of health planning, from the identification of problems and their causes to the design, funding and implementation of public health solutions and the evaluation of whether these solutions really work and are cost-effective in practice.
People live complicated lives and, unlike laboratory scientists who can control all aspects of their experiments, epidemiologists have to work with that complexity. As a result, no epidemiological study can ever be perfect. Even an apparently straightforward survey of, say, alcohol consumption in a community, can be fraught with problems. Who should be included in the survey? How do you measure alcohol consumption reliably? All we can do when we conduct a study is aim to minimise error as far as possible, and then assess the practical effects of any unavoidable error. A critical aspect of epidemiology is, therefore, the ability to recognise potential sources of error and, more importantly, to assess the likely effects of any error, both in your own work and in the work of others. If we publish or use flawed or biased research we spread misinformation that could hinder decision-making, harm patients and adversely affect health policy. Future research may also be misdirected, delaying discoveries that can enhance public health.