Preprint Feed – Epidemiology

medrxiv Subject Collection: Epidemiology This feed contains articles for medRxiv Subject Collection "Epidemiology"

• Associations of physical activity and sedentary time from childhood to adolescence with cognition in adolescence: The PANIC study

  by Jalanko, P., Leppanen, M. H., Bond, B., Laukkanen, J. A., Lakka, T. A., Haapala, E. A. on June 8, 2025 at 12:00 am

  Purpose Investigate the associations of cumulative exposure to physical activity (PA), sedentary time and screen time from childhood to adolescence over an 8-year follow-up with cognition in adolescence. Methods Altogether, 260 adolescents (136 boys) who were 15-17 years at 8-year follow-up were analysed. PA and sedentary time were assessed using an Actiheart-device, and different types of PA, non-screen-based sedentary time and screen time were assessed by a questionnaire at baseline, 2-year […]

• Causal Inference via Electronic Health Records in the National Clinical Cohort Collaborative: Challenges and Solutions in Long COVID Research

  by Butzin-Dozier, Z., Ji, Y., Wang, L.-C., Anzalone, A. J., Hurwitz, E., Patel, R. C., van der Laan, M., Colford, J. M., Hubbard, A. E., on behalf of the N3C Consortium on June 8, 2025 at 12:00 am

  Observational analyses of electronic health record (EHR) data using databases such as the National Clinical Cohort Collaborative include unique challenges for researchers seeking causal inferences, particularly when evaluating subjectively-defined outcomes like Long COVID. We explore several challenges and describe potential solutions. 1. Lack of true negatives: Many diagnoses and conditions either have a positive indicator or a missing status, requiring investigators to carefully consider […]

• Effectiveness of influenza vaccination against infection in UK healthcare workers during winter 2023-24: the SIREN cohort study

  by McGeoch, L. J., Foulkes, S., Whitaker, H., Munro, K., Khawam, J., Sparkes, D., Charlett, A., Brown, C., Atti, A., Islam, J., Hopkins, S., Andrews, N., Hall, V. on June 8, 2025 at 12:00 am

  Objectives To determine vaccine effectiveness against influenza infection among UK healthcare workers between 1 September 2023 and 31 March 2024. Methods We conducted a prospective cohort study, including hospital-based healthcare workers (HCWs) enrolled in the SARS-CoV-2 Immunity & Reinfection Evaluation (SIREN) study. Participants completed fortnightly influenza PCR testing and questionnaires. Influenza vaccination status was identified from national vaccination records and […]

• Design characteristics of Sequential Multiple Assignment Randomized Trials (SMARTs) for human health: a scoping review of studies between 2009-2024

  by Freeman, N. L. B., Browder, S. E., Rowland, B. T., Jones, E. P., Hoch, M., Kim, A. H., Zhou, C. W., Kahkoska, A. R., McGinigle, K. L., Ivanova, A., Kosorok, M. R., Anstrom, K. J. on June 8, 2025 at 12:00 am

  STRUCTURED ABSTRACT Objective: To characterize the reporting practices of sequential multiple assignment randomized trials (SMARTs) in human health research. Design: Scoping review of protocol and primary analysis papers describing SMARTs published between January 2009 and January 2024. Background: SMARTs are innovative trial designs that allow for multiple stages of randomization to treatment based on a patient’s responses to previous treatments. They are uniquely designed to develop […]

• Exploring Novel Kinetics of Automated H2O2 Nebulization: A Breakthrough in SARS-CoV-2 Elimination.

  by Solano-Parada, J., Sanchez-Martinez, J. A., Gomez-Hernandez, B. C., Barriga, M., Garcia-Velasco, P., Fernandez, A., Cornet-Gomez, A., Osuna Carrillo, A., Fabregas, R., Morales-Garcia, C. on June 7, 2025 at 12:00 am

  Although hydrogen peroxide (H2O2) nebulization has shown promise for reducing SARS-CoV-2 loads in healthcare settings, its precise kinetics and real-world efficacy remain incompletely understood. In this prospective environmental sampling study, we collected air and surface samples from COVID-19 patient rooms before and after automated H2O2 nebulization, quantifying viral RNA by RT-qPCR and viral antigens by indirect ELISA, while assessing infectivity via Vero E6 cell cultures. A piecewise […]

• Urbanization exacerbates age-associated declines in cardiometabolic health in Turkana and Orang Asli

  by Watowich, M., Brassington, L., Longtin, A., Wang, S., Rossow, R., Reinhardt, K., John, E., Kahumbu, J. C., Kinyua, P., Lopurudoi, A., Lotukoi, F., Mwai, C. M., Muhoya, B., Mukoma, B., Huat, T. B. T. A. T. B., Tam, K. L., Lim, Y. A., Martins, D., Njeru, S., Seong, N. K., Venkataraman, V. V., Wallace, I. J., Ayroles, J. F., Gurven, M., Kraft, T. S., Lea, A. J. on June 7, 2025 at 12:00 am

  Declines in cardiometabolic health among older individuals are so ubiquitous in Western, high-income countries that non-communicable diseases (NCDs) like type 2 diabetes, hypertension, and cardiovascular disease have been termed "diseases of aging". In contrast, research from non-industrial contexts has found low rates of cardiometabolic NCDs in old age, suggesting protective effects of lifestyle. To test if industrialization and urbanization generates or magnifies age-associated […]

• Early life adversity and late life dementia in the Harmonised Cognitive Assessment Protocol network (U.S., China, England and Europe)

  by Tampubolon, G., Li, G. on June 7, 2025 at 12:00 am

  Social progress and medical advances since the last century have raised uneven global challenges. The Lancet commission on dementia released a recent estimate and projection of dementia: more than 57 million older adults today and nearly triple that number in 25 years, mostly in developing nations. Its life course frame is expansive on modifiable risk factors in mid and late life but restrained on early life. MATERIALS AND METHODS We rectify this omission, assembling harmonised cognitive […]

• Defining Epidemiologically Relevant Units of Cholera Transmission in sub-Saharan Africa

  by DiPrete, B. L., Perez-Saez, J., Wohl, S., Matteson, N., Kim, S., Azman, A., Lessler, J. on June 7, 2025 at 12:00 am

  Much remains unknown about cholera transmission dynamics in Africa. Applying both traditional phylogeographic techniques and novel methods for combining epidemiologic and genomic data, we identified 3-4 distinct "cholera transmission units" within which cross-border cholera transmission has been more frequent. These units can be grouped into two major transmission clusters, one in Western Africa and bordering countries, and one spanning the Central, Eastern, and Southern regions. […]

• serocalculator, an R package for estimating seroincidence from cross-sectional serological data

  by Lai, K. W., Orwa, C., Seidman, J. C., Garrett, D. O., Saha, S. K., Tamrakar, D., Qamar, F. N., Charles, R., Andrews, J. R., Aiemjoy, K., Morrison, D. E. on June 6, 2025 at 12:00 am

  Motivation: Seroincidence–the rate of new infections in a population–is a key measure for understanding pathogen transmission dynamics and informing public health action. Estimating seroincidence from cross-sectional data is complicated by antibody waning, cross-reactivity, and individual heterogeneity in antibody responses. Implementation: serocalculator is an open-source R package that uses a likelihood-based framework incorporating antibody decay models, biological variability, and […]

• The role of hormonal contraceptive use in mediating socio-demographic predictors of overweight/obesity among women of reproductive age in Ghana

  by Issifu, S., Asante, L. S., Sumaila, I., Appietuah, D. A., Twum, A., Agodzo, H., Opoku-Mireku, M. on June 6, 2025 at 12:00 am

  Background The global rise in overweight and obesity poses significant public health challenges, contributing to premature mortality and preventable disabilities. Moreover, efforts to increase reproductive autonomy through modern contraceptive methods are underway, with concerns regarding their potential influence on weight gain. This study aimed to identify the risk factors associated with overweight and obesity and to examine the mediating role of hormonal contraceptive use among Ghanaian […]

• Impact of socio-environmental determinants and hygiene practices in tungiasis transmission in a vulnerable rural community

  by Olusegun-Joseph, T. S., Shafie, N. J., Olusegun-Joseph, D. A., Fowora, M. A., Rufai, M. A., Awoniyi, A. M., Adeleke, M. A. on June 6, 2025 at 12:00 am

  Tungiasis is a neglected tropical disease (NTD) caused by the penetration of adult female Tunga fleas into the skin of humans and animals. The disease disproportionately affects individuals in tropical and subtropical regions, particularly in sub-Saharan Africa, South America and the Caribbean, where poverty, inadequate sanitation and limited healthcare services facilitate transmission, especially among vulnerable populations. To evaluate the association between socio-environmental factors and […]

• Effectiveness and Challenges of Digital Tools Implementation for Enhancing Infectious Disease Surveillance Data Quality in Low- and Middle-Income Countries: A Systematic Review Protocol

  by Olu-Abiodun, O., Faturoti, A., Adepoju, A., Adeloye, D., Adebiyi, A., Abiodun, O. on June 6, 2025 at 12:00 am

  Background: Monitoring infectious diseases is essential for preventing and controlling outbreaks, especially in low- and middle-income countries (LMICs), where issues like poor infrastructure, lack of trained staff, and limited resources can make data collection challenging. Digital tools such as mobile health apps and electronic reporting systems show promise in addressing these problems. However, it’s still unclear how well these tools actually improve the quality of data, like how quickly […]

• Updating the epidemiology of blastomycosis and histoplasmosis in the United States, using national electronic health record data, 2013 – 2023

  by Bartels, J. G., Camponuri, S. K., Snow, T. T., Morgan Bustamante, B. L., Kane, N. J., Reynolds, R. M., Lee, A., Hoffman, M., White, T. C., Remais, J. V., Head, J. R. on June 6, 2025 at 12:00 am

  Introduction: Where surveillance data are limited, nationally-representative electronic health records allow for geographic, temporal, and demographic characterization of the fungal diseases blastomycosis and histoplasmosis. Methods: We identified incident blastomycosis and histoplasmosis cases from 2013 to 2023 within Oracle EHR Real-World Data, which comprises 1.6 billion healthcare encounters nationally. To characterize geographic and temporal incidence rates, we used weighted generalized […]

• An exploratory intersectional analysis of syphilis prevalence among people who inject drugs in Montreal, Canada

  by Harney, B. L., Bruneau, J., Martel-Laferriere, V., Larney, S. on June 6, 2025 at 12:00 am

  Background Syphilis notifications have increased among women and heterosexual men in Canada and people who inject drugs (PWID) are an emerging group at risk of infection. We examined syphilis prevalence among PWID and how this varied by intersecting population groups, socio-structural factors and sexual and substance use behaviors. Methods Data were from HEPCO, a cohort study of PWID in Montreal. We tested for syphilis via venipuncture with treponemal testing reflexed to non-treponemal testing […]

• The architecture of exposome-phenome associations

  by Patel, C. J., Ioannidis, J. P., Manrai, A. K. on June 6, 2025 at 12:00 am

  Non-genetic exposures including nutrients, lifestyle factors, consumables, and pollutants substantially contribute to phenotypic variation. Most studies assess only a few exposures or phenotypes, yielding fragmented exposome-phenome relationships. Systematic approaches are needed to quantify how the exposome the totality of environmental exposures relates broadly to clinically relevant phenotypes. We developed a resource benchmarking the role of the exposome using data from the National Health […]

• Deep learning-enabled MRI phenotyping uncovers regional body composition heterogeneity and disease associations in two European population cohorts

  by Mertens, C. J., Haentze, H., Ziegelmayer, S., Kather, J. N., Truhn, D., Kim, S. H., Busch, F., Weller, D., Wiestler, B., Graf, M., Bamberg, F., Schlett, C. L., Weiss, J. B., Ringhof, S., Can, E., Schulz-Menger, J., Niendorf, T., Lammert, J., Molwitz, I., Kader, A., Hering, A., Meddeb, A., Nawabi, J., Schulze, M. B., Keil, T., Willich, S. N., Krist, L., Hadamitzky, M., Hannemann, A., Bassermann, F., Rueckert, D., Pischon, T., Hapfelmeier, A., Makowski, M. R., Bressem, K. K., Adams, L. C. on June 6, 2025 at 12:00 am

  Body mass index (BMI) does not account for substantial inter-individual differences in regional fat and muscle compartments, which are relevant for the prevalence of cardiometabolic and cancer conditions. We applied a validated deep learning pipeline for automated segmentation of whole-body MRI scans in 45,851 adults from the UK Biobank and German National Cohort, enabling harmonized quantification of visceral (VAT), gluteofemoral (GFAT), and abdominal subcutaneous adipose tissue (ASAT), liver […]

• Prolonged Hospitalization Among Children Aged <5 years Admitted With Acute Gastroenteritis at Siaya County Referral Hospital, in Rural Western Kenya: 2010-2020

  by Awuor, A. O., Ogwel, B., Nyawanda, B. O., Apondi, E., Anyango, R., Khagayi, S., Ochieng, B. J., Muok, E., Munga, S., Ayodo, G., Akello, V., Kibet, S., Mwenda, J. M., Parashar, U., Tate, J. E., Omore, R. on June 6, 2025 at 12:00 am

  Background: Acute gastroenteritis (AGE) causes substantial morbidity and mortality in children <5 years old accounting for 9 million hospitalizations. Prolonged hospitalization can cause dire consequences to the patient and healthcare system. However, data on factors associated with prolonged hospitalization for AGE in developing countries are limited. Objectives: We aim to describe trends and assess factors associated with prolonged hospitalization among children <5 years admitted with […]

• Associations of menstrual health with school absenteeism and educational performance among Ugandan secondary school students: A longitudinal study

  by Baleke, C., Mugenyi, L., Nelson, K. A., Thomas, K. A., Ndekezi, D., Enomut, J. R., Alezuyo, C., Jerrim, J., Weiss, H. A. on June 5, 2025 at 12:00 am

  BackgroundRelatively few studies have quantified the amount of school missed due to poor menstrual health, or the impact of menstrual health on educational performance. MethodsWe analysed baseline and longitudinal data from participants in a cluster-randomised trial of a menstrual health intervention in 60 Ugandan secondary schools. We measured school absenteeism as the self-reported number of days absent due to menstruation per month and assessed educational performance using examination […]

• Impact of Mass Drug Administration with Ivermectin, Diethylcarbamazine, and Albendazole in Elimination of Lymphatic Filariasis in Five Districts of Nepal

  by Mahato, R. K., Dahal, G., Ghimire, Y. C., Marasini, R. P., Hayman, D. T. S., Krishnamoorthy, K., Sharma, S. R., Sah, D., Ray, R. B., Subedi, R., Pandit, K. R., Khatiwada, S. R., Ojha, A. B., Mahaseth, S., Mahata, D. B., Brady, M., Brucker, C. R. B., Stone, B., Parajuli, A., Paudel, S. R., Devkota, B. P., Jha, C. B., Paudel, K. P., Sapkota, B. P., Bajracharya, B. on June 4, 2025 at 12:00 am

  BackgroundNepal aims to eliminate Lymphatic Filariasis (LF) by 2030. Mass drug administration (MDA) has ceased in 53 of 64 endemic districts. In 2023, five districts with persistent LF ([≥]2% antigen prevalence) completed two rounds of MDA using a three-drug regimen (Ivermectin, Diethylcarbamazine, and Albendazole; IDA), achieving over 65% coverage. An Epidemiological Monitoring Survey (EMS) was conducted to evaluate IDAs impact. MethodsA cross-sectional EMS was conducted 9 months post-MDA […]

• Adverse events in both childhood and adulthood are associated with molecular, clinical and functional markers of ageing

  by Aas, M., Hoppen, T. H., Morina, N., Zhang, S., Li, B., Mlakar, V., Mutz, J. on June 4, 2025 at 12:00 am

  Adverse events, including interpersonal trauma, have been linked to poorer health outcomes. However, the biological mechanisms linking adversity and health outcomes remain poorly understood. Here, we investigated associations between molecular, clinical and functional markers of biological ageing and adverse events experienced in childhood and adulthood. Using data from the UK Biobank (N = 153,557 middle-aged and older adults), we investigated whether adversity experienced in childhood and/or […]

• Real-world comparative outcomes of GLP-1 RA and semaglutide prescription among individuals with type 2 diabetes

  by Salvatore, M. M., Zhang, B., Tang, H., Lu, Y., Zhang, D., Zhou, T., Lu, Y., Amaro, A., Ritchie, M. D., Chen, Y. on June 4, 2025 at 12:00 am

  Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are increasingly prescribed for type 2 diabetes (T2D) and weight management, yet their broad health impacts in real- world settings remain understudied. Using data from the All of Us Research Program (n=18,746), we conducted both intention-to-treat and per-protocol phenome-wide association studies comparing diagnoses following GLP-1 RA prescription, including semaglutide-specific analyses, to those following sodium-glucose cotransporter-2 […]

• The time- and space-varying roles of human mobility in shaping urban dengue epidemics

  by Mills, C., dos Santos de Sousa, G., Silva Lima Neto, A., Furtado, V., Pei, S., Kraemer, M. U. G., Donnelly, C. A. on June 4, 2025 at 12:00 am

  Dengue outbreaks continue to cause large morbidity and mortality globally. Previous work has shown that human movement alongside weather, climatic, ecological, and socioeconomic factors influence outbreak size, persistence, and geographical spread. However, the relative importance of human movement is unclear for the establishment, rapid expansion, and persistence of dengue in urban settings. Relatedly, the extent to which neighbourhoods differentially influence outbreaks over time is unclear. […]

• When the outcome is compositional – a method for conducting compositional response linear mixed models for physical activity, sedentary behaviour and sleep research.

  by Miatke, A., Stanford, T., Olds, T., Fraysse, F., Maher, C., Martin-Fernandez, J. A., Dumuid, D. on June 4, 2025 at 12:00 am

  Time use is compositional in nature because time spent in sleep, sedentary behaviour and physical activity will always sum to 24 h/day meaning any increase in one behaviour will necessarily displace time spent in another behaviour(s). Given the link between time use and health, and its modifiable nature, public health campaigns often aim to change the way people allocate their time. However, relatively few studies have investigated how movement-behaviour composition changes longitudinally (with […]

• A systematic review of the applications of Mendelian randomization assessing the causal relevance of the gut microbiome in human health and disease

  by Hatcher, C., McKinlay, A., Bailward, A., Dawes, A. C., Hughes, D. A., Pournaras, D. J., Corbin, L. J., Goudswaard, L. J., Spiga, F., Wade, K. H. on June 3, 2025 at 12:00 am

  ObjectivesTo investigate the current application of Mendelian randomization (MR) in assessing the causal relevance of the gut microbiome in human health and evaluate the quality of these studies. DesignSystematic review Data sourcesOvid MEDLINE, Embase, Web of Science, bioRxiv and medRxiv were searched from inception to the 12th of January 2023. Eligibility criteriaFull-texts and conference abstracts of studies that conducted MR analyses to investigate the causal role of the gut microbiome […]

• Academic Impairment from Sleep Difficulties: The Role of Substance Use, Psychological Distress, and Loneliness in U.S. College Students

  by chung, s. on June 3, 2025 at 12:00 am

  Sleep-related academic impairment is a common issue among college students and may be influenced by psychological and behavioral health factors. This study used data from the Spring 2021 American College Health Association-National College Health Assessment III (ACHA-NCHA III) to examine whether psychological distress, loneliness, and substance use were associated with academic impairment due to sleep difficulties among U.S. college students aged 18-24 (N = 798). Logistic regression showed that […]

• Comparison of sedentary time calculated from count- and raw accelerometer data: The Tromso Study

  by Weitz, M., Morseth, B., Hopstock, L. A., Brage, S., Horsch, A. on June 3, 2025 at 12:00 am

  Accelerometers have become a popular and indispensable tool to objectively measure various aspects of daily behavior. While physical activity can be estimated relatively easy, sedentary behavior requires reliable Time in Bed and non-wear time algorithms. Over the years, various algorithms have been proposed, but little is known about how these algorithms quantitatively influence the estimation of sedentary behavior. In this study, we systematically compared different data processing strategies […]

• Rationale and study protocol of the MAMELI Cohort study (MApping the Methylation of repetitive elements to track the Exposome effects on health: the city of Legnano as a LIving lab)

  by Bollati, V., Rota, F., Dioni, L., Favero, C., Iodice, S., Gallazzi, M., Spinazze, A., Fanti, G., Campagnolo, D., Nardi, T., Biganzoli, D., Dariol, E., Matsagani, R., Hoxha, M., Monti, P., Albetti, B., Tarantini, L., Barbuto, D., Luconi, E., Marano, G., Biganzoli, G., Biciuffi, R., Boracchi, P., Cavallo, D. M., Guerrieri, P. M., Mosca, F., Gustincich, S., Sanesi, G., Ferrari, L., Carugno, M., Fustinoni, S., Pesatori, A. C., Pandolfini, L., Miragoli, M., Cattaneo, A., Biganzoli, E. on June 3, 2025 at 12:00 am

  BackgroundThe concept of the exposome encompasses all the factors influencing human health throughout the life course. The exposome induces epigenetic changes, such as DNA methylation, which influence gene expression and impact overall health. Several recent studies have explored how repetitive elements (REs) in the genome can be activated in response to environmental stimuli. However, most of these investigations have assumed that altered RE methylation is always detrimental to individual […]

• Spanish-version of the Posttraumatic Stress Disorder Checklist for DSM-5 (PCL-5) in health-workers

  by Villarreal-Zegarra, D., De la Cruz-Torralva, K., Barrera-Begazo, J., Rosales-Rimache, J., Soto-Becerra, P., Vilela-Estrada, A. L., Diaz, C., Apolaya, M., Lea, R., Reategui-Rivera, C. M., Garcia, F. E. on June 2, 2025 at 12:00 am

  BackgroundThe Posttraumatic Stress Disorder Checklist (PCL-5) is one of the most widely used instruments for assessing posttraumatic stress disorder (PTSD), adapted to meet DSM-5 criteria. Establishing a validated online version for Spanish-speaking populations, particularly among healthcare professionals, is essential to ensure accurate assessment aligned with these updated criteria. AimThe purpose is to evaluate the psychometric properties of the online Spanish version of the PCL-5 for […]

• SPATIAL ANALYSIS OF MORTALITY DUE TO CONGENITAL SYPHILIS IN BRAZIL FROM 2008 TO 2022

  by Pinheiro, Y. T., da Silva, R. A. R., Costa, K. T. d. S., Oliveira, A. G. R. d. C., da Costa, J. D., Marinho, C. d. S. R., de Freitas Filho, J. A., Rocha, L. K. A., Moreira, V. S., Monteiro, R. C. d. Q., Holanda, J. R. R. on June 2, 2025 at 12:00 am

  The objective of this study is to analyze spatial distribution of mortality due to congenital syphilis in Brazil from 2008 to 2022. This is an ecological study that considered congenital syphilis deaths reported in all Brazilian municipalities, from 2008 to 2022, available in the Brazilian governments information systems. We built a thematic map to describe the distribution of congenital syphilis mortality in the country and, subsequently, applied the Local Index Spatial Analysis to identify […]

• Reproduction numbers for epidemics with hidden cases, re-infections and newborns

  by Nesteruk, I. on June 2, 2025 at 12:00 am

  Real-time assessments of the reproduction rates are crucial for timely responses to changes in epidemic dynamics. Known effective reproduction numbers Rt are based on registered (visible) cases despite that asymptomatic and unregistered patients occur in all epidemics and need to be corrected to take into account the number of hidden cases. Since newborns and re-infections significantly affect the dynamics of epidemics, they should also be taken into account in calculations of Rt and recently […]