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BACKGROUND: Individual immune responses to SARS-CoV-2 are well-studied, while the combined effect of these responses on population-level immune dynamics remains poorly understood. Given the key role of population immunity on pathogen transmission, delineation of the factors that drive population immune evolution has critical public health implications. METHODS: We enrolled individuals 5 years and older selected using a multistage cluster survey approach in the Northwest and Southeast of the Dominican Republic. Paired blood samples were collected mid-pandemic (Aug 2021) and late pandemic (Nov 2022). We measured serum pan-immunoglobulin antibodies against the SARS-CoV-2 spike protein. Generalized Additive Models (GAMs) and random forest models were used to analyze the relationship between changes in antibody levels and various predictor variables. Principal component analysis and partial dependence plots further explored the relationships between predictors and antibody changes. FINDINGS: We found a transformation in the distribution of antibody levels from an irregular to a normalized single peak Gaussian distribution that was driven by titre-dependent boosting. This led to the convergence of antibody levels around a common immune setpoint, irrespective of baseline titres and vaccination profile. INTERPRETATION: Our results suggest that titre-dependent kinetics driven by widespread transmission direct the evolution of population immunity in a consistent manner. These findings have implications for targeted vaccination strategies and improved modeling of future transmission, providing a preliminary blueprint for understanding population immune dynamics that could guide public health and vaccine policy for SARS-CoV-2 and potentially other pathogens. FUNDING: The study was primarily funded by the Centers for Disease Control and Prevention grant U01GH002238 (EN). Salary support was provided by Wellcome Trust grant 206250/Z/17/Z (AK) and the Australian National Health and Medical Research Council Investigator grant APP1158469 (CLL).
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BACKGROUND: Understanding mortality among travellers is essential for mitigating risks and enhancing travel safety. However, limited evidence exists on severe illnesses and injuries leading to death among travellers, particularly in low- and middle-income countries and remote regions. METHODS: We conducted a retrospective census study using country-level observational data from death certificates of travellers of seven South American countries (Argentina, Brazil, Chile, Colombia, Ecuador, Peru, and Uruguay) from 2017 to 2021. Causes of death were evaluated using ICD-10 codes, categorised into non-communicable diseases (NCDs), communicable diseases, and injuries. We quantified causes of death by demographic characteristics (e.g. age, sex), and geographical variables. Chi-square tests were used to assess differences between categories. We calculated crude mortality rates and incidence rate ratios (IRRs) per country's subregions. RESULTS: A total of 17 245 deaths were reported. NCDs (55%) were the most common cause of death, followed by communicable diseases (23.4%) and injuries (18.1%). NCD-associated deaths increased after age 55 years and were highest among ≥85 years. Communicable diseases were more common at younger age (<20 years). Injury-associated deaths were more common in men (79.9%) and 25-29-year-olds (17.1%). Most deaths (68.2%) could have been avoided by prevention or treatment. Mortality risk was higher among travellers in bordering regions between countries. In Roraima [Brazil] and Norte de Santander [Colombia], locations bordering Venezuela, the death incidence rate ratio was 863 and 60, respectively. These countries' reference mortality rates in those regions were much lower. More than 80% of the deaths in these border regions of Brazil and Colombia involved Venezuelan citizens. Conclusion: The study identified risk factors and high-risk locations for deaths among travellers in seven countries of South America. Our findings underscore the need for specific health interventions tailored to traveller demographics and destination to optimise prevention of avoidable deaths in South America.
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OBJECTIVE: This study investigates the role of trust in shaping COVID-19 vaccine acceptance in the Dominican Republic (DR) during the COVID-19 pandemic. DESIGN: Cross-sectional household survey. SETTING: Randomly selected households across 134 clusters in the DR, from 30 June 2021 to 12 October 2021. PARTICIPANTS: 5999 participants ≥16 years of age were enrolled. OUTCOME MEASURES: COVID-19 vaccine hesitancy (CVH) data were collected from participants ≥16 years of age and analysed as both an ordinal and binary variable. RESULTS: Overall, CVH was low (5.2% (95% CI 4.6% to 5.8%)), but more common among younger individuals, women and individuals of Mestizo ethnicity. Higher trust in local government, national government, scientists and local doctors (considered official sources) was associated with lower odds of CVH (OR 0.89 (95% CI 0.72 to 0.88), 0.89 (95% CI 0.81 to 0.98), 0.87 (95% CI 0.80 to 0.94) and 0.70 (95% CI 0.62 to 0.80), respectively). Higher trust in religious leaders, social media and traditional media (considered unofficial sources) was associated with higher odds of CVH, with respective ORs of 1.32 (95% CI 1.18 to 1.47), 1.30 (95% CI 1.19 to 1.41) and 1.08 (95% CI 0.97 to 1.22). CONCLUSION: We report findings on CVH from a national household survey in the DR and identify overall low rates of CVH but marked heterogeneity by age, gender and ethnicity. Trust in unofficial versus official sources of information is associated with increased CVH. These findings highlight and quantify the importance of trust as a key parameter when considering public health communication strategies.
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Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Confianza , Vacilación a la Vacunación , Humanos , República Dominicana , Femenino , Masculino , Estudios Transversales , Adulto , COVID-19/prevención & control , COVID-19/epidemiología , Persona de Mediana Edad , Vacunas contra la COVID-19/administración & dosificación , Vacilación a la Vacunación/psicología , Vacilación a la Vacunación/estadística & datos numéricos , Adulto Joven , Adolescente , Anciano , Encuestas y CuestionariosRESUMEN
BACKGROUND: Despite the World Health Organisation certifying China malaria-free in 2021, the risk of local transmission caused by imported malaria cases remains a significant clinical and public health issue. It is necessary to present the changing trends of malaria in China and discuss the role of travel medicine services in consolidating malaria elimination. METHODS: This study systematically reviewed articles and reports related to human malaria from 2013 to 2022 published in international and Chinese databases. Data on malaria (i.e. number of cases, Plasmodium spp., diagnostic method, country of acquisition, provinces with high risk of re-introduction and transmission) were collected and synthesised, then summarised using descriptive statistics. RESULTS: Overall, 24 758 cases of malaria (>99.5% laboratory confirmed, > 99.2% imported, 0.5% fatal) were reported in China from 2013 to 2022, with a downward trend over the years (4128 cases in 2013 compared to 843 cases in 2022; χ2 trend p-value = 0.005). The last locally acquired case was reported in 2017. P. falciparum (65.5%) was the most common species identified, followed by P. vivax (20.9%) and P. ovale (10.0%). Two Pheidole knowlesi cases were also identified in 2014 and 2017 in returned travellers from Malaysia and Indonesia, respectively. The most common countries of malaria acquisition were Ghana, Angola, and Myanmar. P. vivax was mainly detected in returned travellers from Myanmar, while P. falciparum and P. ovale were detected in travellers from Sub-Saharan Africa. Imported cases were mainly reported in Yunnan, Jiangsu, Sichuan, Guangxi, Shandong, Zhejiang, and Henan provinces, where large numbers of Chinese people travel overseas for work. CONCLUSION: Returned travellers from malaria-endemic countries pose a significant risk of malaria re-introduction to China. Travel medicine should be strengthened to improve the capacity and accessibility of both pre- and post-travel services, including malaria prophylaxis and prompt diagnosis of illness in returned travellers.
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BACKGROUND: The aim of this study was to compare the diagnostic performance of native antigen ELISAs and ADAMU-AE/CE commercial ICT test kits in subjects either exposed to Echinococcus infection or with clinically diagnosed alveolar (AE) or cystic (CE) echinococcosis. METHODS: A total of 370 subjects with a previous clinical confirmation of CE or AE from northwestern China were recruited. Serum samples were also obtained from 3923 children/teenagers during a community survey. All sera were tested using native antigen ELISAs. The ADAMU-AE/CE test kits were subsequently used for the serology of the 370 clinically confirmed individuals and of 251 children/teenagers that were ELISA antibody-positive for both Echinococcus species but ultrasound-negative during baseline survey. An analysis of the association between the serological tests and ultrasound classification was carried out amongst 89 AE and 164 CE cases. A Kappa consistency analysis was undertaken to compare the diagnostic performance of the native antigen ELISAs and the ADAMU kits and the ultrasound imaging results. The χ² test was also used for a comparison of the different seropositivity rates between the groups. FINDINGS: There was poor consistency (Kappa = 0.26 and 0.28 for AE and CE respectively) between the native antigen ELISAs and the ADAMU kits for the diagnosis of AE and CE among the cases and the surveyed children/teenagers, but a relatively good consistency (Kappa = 0.63) between the ADAMU-AE kit and ultrasound observations for the AE cases. Additionally, of the 251 teenagers co-positive for both AE and CE antibodies by the native antigen ELISAs, only one was found positive by the ADAMU-AE kit, verified as a new AE case on subsequent ultrasound follow-up. The remainder (N = 250) were negative by serology using the ADAMU-AE/CE kits and by ultrasound examination. The two native antigen ELISAs did not discriminate well between cases of clinically diagnosed AE and CE. In contrast, ADAMU-AE and ADAMU-CE commercial ICT test kits readily differentiated cases of AE from CE with specificities of 99% for AE and 100% for CE. CONCLUSIONS: The ADAMU-AE/CE kits proved reliable, accurate, and amenable diagnostic tools in the clinical setting for confirmation of suspected AE/CE cases. The native antigen ELISAs tests can provide useful information on the level of human exposure to Echinococcus infection.
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BACKGROUND: Soil transmitted helminth (STH) infections are estimated to impact 24% of the world's population and are responsible for chronic and debilitating morbidity. Disadvantaged communities are among the worst affected and are further marginalized as infection prevalence fuels the poverty cycle. Ambitious targets have been set to eliminate STH infections, but accurate epidemiological data will be required to inform appropriate interventions. This paper details the protocol for an analysis that aims to produce spatial prediction mapping of STH prevalence in the Western Pacific Region (WPR). METHODS: The protocol follows the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol (PRISMA-P) guidelines. The study design will combine the principles of systematic review, meta-analysis, and geospatial analysis. Systematic searches will be undertaken in PubMed, Scopus, ProQuest, Embase, and Web of Science for studies undertaken post 2000, to identify surveys that enable the prevalence of human STH infection within the WPR to be calculated. Covariate data for multivariable analysis will be obtained from publicly accessible sources. Survey data will be geolocated, and STH prevalence and covariates will be linked to produce a spatially referenced dataset for analysis. Bayesian model-based geostatistics will be used to generate spatially continuous estimates of STH prevalence mapped to a resolution of 1 km2. A separate geospatial model will be constructed for each STH species. Predictions of prevalence will be made for unsampled locations and maps will be overlaid for each STH species to obtain co-endemicity maps. DISCUSSION: This protocol facilitates study replication and may be applied to other infectious diseases or alternate geographies. Results of the subsequent analysis will identify geographies with high STH prevalence's and can be used to inform resource allocation in combating this neglected tropical disease. TRIAL REGISTRATION: Open Science Framework: osf.io/qmxcj.
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Helmintiasis , Helmintos , Suelo , Animales , Humanos , Teorema de Bayes , Helmintiasis/epidemiología , Helmintiasis/transmisión , Metaanálisis como Asunto , Prevalencia , Suelo/parasitología , Revisiones Sistemáticas como AsuntoRESUMEN
Background: The Philippines reports a high prevalence of soil-transmitted helminth (STH) infections despite the implementation of nationwide mass drug administration since 2006. The spatial variation of STH infections in the Philippines was last described using the 2005-2007 national STH and schistosomiasis survey. This study aimed to identify sociodemographic and environmental factors that drive STH transmission and predict high-risk areas in the Philippines. Methods: Epidemiological data on STH for students aged 5-16 years were obtained from the 2015 Philippines National Prevalence survey, while environmental data were extracted from satellite images and publicly available sources. Model-based geostatistics, implemented in a Bayesian framework, was used to identify sociodemographic and environmental correlates and predict high-risk areas for STH across the Philippines. The best-fitting model with the lowest deviance information criterion (DIC) was used to interpret the findings of the model and predict STH infection risk for the entire country. Risk maps were developed for each STH infection using the posterior means derived from the model. Findings: The prevalence of Ascaris lumbricoides (20.0%) and Trichuris trichiura (29.3%) was higher in the Visayas Island than in the Luzon and Mindanao Islands. Hookworm prevalence was highest in Mindanao Island (1.3%). Risk of A. lumbricoides was positively associated with males (odds ratio [OR]: 1.197; 97.5% Credible Interval [CrI]: 1.114, 1.286) and temperature (OR: 1.148; 97.5% CrI: 1.033, 1.291), while normalized difference vegetation index (OR: 0.354; 97.5% CrI: 0.138, 0.930) and soil pH (OR: 0.606; 97.5% CrI: 0.338, 0.949) were negatively associated with the transmission. T. trichiura risk was positively associated with males (OR: 1.261; 97.5% CrI: 1.173, 1.341), temperature (OR: 1.153; 97.5% CrI: 1.001, 1.301), and rainfall (OR: 1.004; 97.5% CrI: 1.011, 1.069). Hookworm risk was positively associated with males (OR: 2.142; 97.5% CrI: 1.537, 2.998), while children aged ≤12 years (OR: 0.435; 97.5% CrI: 0.252, 0.753) had a negative association with risk compared to those over 12 years. Focal areas of high risk were identified for A. lumbricoides and T. trichiura in the Visayas Island, and hookworm in the Mindanao Island. Interpretation: The spatial distribution of all three STH infections has considerably decreased since a previous national risk-mapping exercise. The high-risk areas identified in the study can be used to strategically target deworming and health education activities to further reduce the burden of STH and support progress toward elimination. Funding: The Australian Centre for the Control and Elimination of Neglected Tropical Diseases and the Australian National Health and Medical Research Council.
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Incidence of COVID-19 has been associated with sociodemographic factors. We investigated variations in SARS-CoV-2 seroprevalence at sub-national levels in the Dominican Republic and assessed potential factors influencing variation in regional-level seroprevalence. Data were collected in a three-stage cross-sectional national serosurvey from June to October 2021. Seroprevalence of antibodies against the SARS-CoV-2 spike protein (anti-S) was estimated and adjusted for selection probability, age, and sex. Multilevel logistic regression was used to estimate the effect of covariates on seropositivity for anti-S and correlates of 80% protection (PT80) against symptomatic infection for the ancestral and Delta strains. A total of 6683 participants from 134 clusters in all 10 regions were enrolled. Anti-S, PT80 for the ancestral and Delta strains odds ratio varied across regions, Enriquillo presented significant higher odds for all outcomes compared with Yuma. Compared to being unvaccinated, receiving ≥2 doses of COVID-19 vaccine was associated with a significantly higher odds of anti-S positivity (OR 85.94, [10.95-674.33]) and PT80 for the ancestral (OR 4.78, [2.15-10.62]) and Delta strains (OR 3.08, [1.57-9.65]) nationally and also for each region. Our results can help inform regional-level public health response, such as strategies to increase vaccination coverage in areas with low population immunity against currently circulating strains.
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OBJECTIVE: Calculate the incidence of SARS-CoV-2 (COVID-19) infection notifications and the influence of area-level geographic and socioeconomic factors in Queensland using real-time data from the COVID-19 Real-time Information System for Preparedness and Epidemic Response (CRISPER) project. DESIGN AND SETTING: Population-level ecological study and spatial mapping of the incidence of COVID-19 infection notifications in Queensland, by postcode, 2020-2022. MAIN OUTCOME MEASURES: Proportions and distribution of COVID-19 infection notifications by year, age-group, socioeconomic disadvantage, and geospatial mapping. Incidence rate ratios (IRRs) were calculated. RESULTS: Between 28 January 2020 and 30 June 2022, a total of 609,569 cases of COVID-19 associated with a Queensland postcode were recorded. The highest proportion of cases occurred in 2022 (96.5%), and in the 20- to 24-year age category (IRR = 1.787). In non-Major City areas, there was also a higher incidence of COVID-19 cases in lower socioeconomic areas (IRR = 0.84) than in higher socioeconomic areas (IRR = 0.66). CONCLUSIONS: Queensland experienced its highest proportion of COVID-19 cases once domestic and international borders opened. However, geographic and socioeconomic factors may have still contributed to a higher incidence of COVID-19 cases across some Queensland areas. IMPLICATIONS FOR PUBLIC HEALTH: Although Australia has moved from the emergency response phase of the COVID-19 pandemic, we need to ensure ongoing prevention strategies target groups and areas that we have identified with the highest incidence.
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COVID-19 , Humanos , COVID-19/epidemiología , Queensland/epidemiología , SARS-CoV-2 , Incidencia , Pandemias , Factores SocioeconómicosRESUMEN
BACKGROUND: American Samoa successfully completed seven rounds of mass drug administration (MDA) for lymphatic filariasis (LF) from 2000-2006. The territory passed the school-based transmission assessment surveys in 2011 and 2015 but failed in 2016. One of the key challenges after the implementation of MDA is the identification of any residual hotspots of transmission. METHOD: Based on data collected in a 2016 community survey in persons aged ≥8 years, Bayesian geostatistical models were developed for LF antigen (Ag), and Wb123, Bm14, Bm33 antibodies (Abs) to predict spatial variation in infection markers using demographic and environmental factors (including land cover, elevation, rainfall, distance to the coastline and distance to streams). RESULTS: In the Ag model, females had a 26.8% (95% CrI: 11.0-39.8%) lower risk of being Ag-positive than males. There was a 2.4% (95% CrI: 1.8-3.0%) increase in the odds of Ag positivity for every year of age. Also, the odds of Ag-positivity increased by 0.4% (95% CrI: 0.1-0.7%) for each 1% increase in tree cover. The models for Wb123, Bm14 and Bm33 Abs showed similar significant associations as the Ag model for sex, age and tree coverage. After accounting for the effect of covariates, the radii of the clusters were larger for Bm14 and Bm33 Abs compared to Ag and Wb123 Ab. The predictive maps showed that Ab-positivity was more widespread across the territory, while Ag-positivity was more confined to villages in the north-west of the main island. CONCLUSION: The findings may facilitate more specific targeting of post-MDA surveillance activities by prioritising those areas at higher risk of ongoing transmission.
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Filariasis Linfática , Filaricidas , Masculino , Femenino , Animales , Humanos , Filariasis Linfática/tratamiento farmacológico , Wuchereria bancrofti , Samoa Americana/epidemiología , Teorema de Bayes , Antígenos Helmínticos , Anticuerpos Antihelmínticos , Demografía , Filaricidas/uso terapéuticoRESUMEN
Histoplasmosis, caused by the thermally dimorphic fungus Histoplasma spp., is a disease with a broad clinical spectrum, presenting from asymptomatic/flu-like symptoms to progressive disseminated disease in people with immunosuppression. In recent years, the concept of histoplasmosis as a disease restricted to the American continent has changed, as now histoplasmosis is reported in many regions around the world. In Latin America, histoplasmosis represents a threat, especially in people with advanced HIV disease (AHD). Diagnosis of histoplasmosis in people living with HIV (PLHIV) is challenging due to the low index of suspicion of the disease, non-specificity of signs and symptoms, and limited access to specific laboratory testing, while the diagnostic delay is significantly associated with mortality. In the last decade, novel diagnostic tests have been developed for the rapid detection of histoplasmosis, such as commercial kits for antigen detection. Furthermore, advocacy groups were created that presented histoplasmosis as a public health problem, with emphasis on patients at risk of progressive disseminated disease. This review aims to discuss the impact of histoplasmosis associated with AHD in Latin America and the strategies employed to tackle histoplasmosis, from the implementation of laboratory testing to disease advocacy and public health interventions.
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Introducción: el aumento de las enfermedades crónicas es una de las mayores amenazas para la salud y la sostenibilidad de los sistemas de atención. Para ello, los ajustes del riesgo permiten desarrollar programas de clasificación de la población y se vuelven instrumentos para implementar nuevos modelos de atención, estructurados a partir de la morbilidad, clasificando el riesgo con el gasto asociado, y así desarrollar modelos predictivos y análisis del gasto per cápita según las características de la población, con lo cual se logra una mejor gestión financiera. Como atención primaria, la gestión del riesgo debe anticiparse a las enfermedades para diagnosticarlas de manera precoz y brindar tratamientos oportunos orientados a disminuir la severidad y secuelas. Algunas ocasionan grandes costos para el sistema de salud afectando su equilibrio y sostenibilidad, como la artritis reumatoide (AR), considerada de alto costo por su impacto y la asociación con otras comorbilidades. Objetivo: revisar los estudios realizados sobre carga económica (CE), carga de enfermedad (CE1), gastos de bolsillo, gastos catastróficos en salud (GCS) y calidad de vida relacionada con la salud (CVRS), en pacientes con AR en Colombia y en el mundo entre 2010 y 2022. Métodos: revisión de alcance de 482 artículos, 139 de CE y CE1, 14 de gastos de bolsillo y GCS, y 329 para CVRS, en literatura indexada utilizando las bases Scopus, Medline a través de Pubmed y JSTOR en inglés y español. Resultados: se observó tendencia en el crecimiento de la literatura, pero con predominio de reportes asociados con terapias biológicas tanto en CE y CE1 como CVRS, seguidos de estudios de atención médica y revisiones sistemáticas de literatura (RSL). Estados Unidos lidera las investigaciones seguido del Reino Unido; el cuestionario predominante para evaluar la calidad de vida relacionada con la salud fue el SF-36 (41,9%) seguido del EQ- 5D (19%) y aunque se cuenta con el QolRA (Quality of Life in Rheumatoid Arthritis Scale) validado en Colombia, su uso infrecuente. Conclusiones: el aumento de estudios sobre costos en salud ha tomado gran relevancia para comprender la realidad e instruir sobre aspectos de gestión del riesgo, enseñar conceptos, analizar escenarios de impacto y estudio de sensibilidades, mostrando todos los posibles resultados.
de Medicina y CirugíaREPERT MED CIR. 2023;32(3):197-207198ABSTRACTIntroduction: the rise in chronic diseases is one of the major threats to health and sustainability of care systems. To this end, risk adjustments allow the development of population classiîcation programs which become instruments to implement care models based on morbidity, risk classiîcation and cost, and for developing predictive models and analyzing per capita costs based on population characteristics, leading to achieve a better înancial management. As part of primary care, risk management should anticipate diseases for their early diagnosis and timely treatment, aimed at reducing their severity and sequelae. Some cause great costs for the health care system, aîecting its balance and sustainability, such as, rheumatoid arthritis (RA), considered a high-cost disease, due to its impact and comorbidities. Objective: to review studies on economic burden (EB), burden of disease (BoD1), out-of-pocket expenses, catastrophic health expenditures (CHE) and health-related quality of life (HRQoL), in patients with RA in Colombia and worldwide, between 2010 and 2022. Methods: a scoping review of 482 articles, 139 on EB and BoD1, 14 on out-of-pocket expenses and CHE, and 329 on HRQoL, found in the indexed literature in the Scopus, Medline through Pubmed and JSTOR databases in English and Spanish. Results: a trend in the growth of the literature, was observed, with a predominance of reports on biological therapies, considering EB and BoD1 and HRQoL as well, followed by healthcare studies and systematic literature reviews (SLR). The United States leads this research, followed by the United Kingdom; the most used questionnaire to assess health-related quality of life was the SF-36 (41.9%) followed by the EQ- 5D (19%) and although the QolRA (Quality of Life in Rheumatoid Arthritis Scale) validated in Colombia is available, it is seldom used. Conclusions: the increase of studies on healthcare costs has gained great relevance for learning about reality and creating instructions on risk management, teach concepts, analyze impact scenarios, and study sensitivities, while showing all the possible results. Key words: economic burden, burden of disease, out-of-pocket expenditure, catastrophic expenditure, health-related quality of life, rheumatoid arthritis, scoping review.
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Humanos , ColombiaRESUMEN
Background: Population-level SARS-CoV-2 immunological protection is poorly understood but can guide vaccination and non-pharmaceutical intervention priorities. Our objective was to characterise cumulative infections and immunological protection in the Dominican Republic. Methods: Household members ≥5 years were enrolled in a three-stage national household cluster serosurvey in the Dominican Republic. We measured pan-immunoglobulin antibodies against the SARS-CoV-2 spike (anti-S) and nucleocapsid glycoproteins, and pseudovirus neutralising activity against the ancestral and B.1.617.2 (Delta) strains. Seroprevalence and cumulative prior infections were weighted and adjusted for assay performance and seroreversion. Binary classification machine learning methods and pseudovirus neutralising correlates of protection were used to estimate 50% and 80% protection against symptomatic infection. Findings: Between 30 Jun and 12 Oct 2021 we enrolled 6683 individuals from 3832 households. We estimate that 85.0% (CI 82.1-88.0) of the ≥5 years population had been immunologically exposed and 77.5% (CI 71.3-83) had been previously infected. Protective immunity sufficient to provide at least 50% protection against symptomatic SARS-CoV-2 infection was estimated in 78.1% (CI 74.3-82) and 66.3% (CI 62.8-70) of the population for the ancestral and Delta strains respectively. Younger (5-14 years, OR 0.47 [CI 0.36-0.61]) and older (≥75-years, 0.40 [CI 0.28-0.56]) age, working outdoors (0.53 [0.39-0.73]), smoking (0.66 [0.52-0.84]), urban setting (1.30 [1.14-1.49]), and three vs no vaccine doses (18.41 [10.69-35.04]) were associated with 50% protection against the ancestral strain. Interpretation: Cumulative infections substantially exceeded prior estimates and overall immunological exposure was high. After controlling for confounders, markedly lower immunological protection was observed to the ancestral and Delta strains across certain subgroups, findings that can guide public health interventions and may be generalisable to other settings and viral strains. Funding: This study was funded by the US CDC.
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Under the Global Program to Eliminate Lymphatic Filariasis (LF) American Samoa conducted seven rounds of mass drug administration (MDA) between 2000 and 2006. Subsequently, the territory passed the WHO recommended school-based transmission assessment survey (TAS) in 2011/2012 (TAS-1) and 2015 (TAS-2) but failed in 2016, when both TAS-3 and a community survey found LF antigen prevalence above what it had been in previous surveys. This study aimed to identify potential environmental drivers of LF to refine future surveillance efforts to detect re-emergence and recurrence. Data on five LF infection markers: antigen, Wb123, Bm14 and Bm33 antibodies and microfilaraemia, were obtained from a population-wide serosurvey conducted in American Samoa in 2016. Spatially explicit data on environmental factors were derived from freely available sources. Separate multivariable Poisson regression models were developed for each infection marker to assess and quantify the associations between LF infection markers and environmental variables. Rangeland, tree cover and urban cover were consistently associated with a higher seroprevalence of LF-infection markers, but to varying magnitudes between landcover classes. High slope gradient, population density and crop cover had a negative association with the seroprevalence of LF infection markers. No association between rainfall and LF infection markers was detected, potentially due to the limited variation in rainfall across the island. This study demonstrated that seroprevalence of LF infection markers were more consistently associated with topographical environmental variables, such as gradient of the slope, rather than climatic variables, such as rainfall. These results provide the initial groundwork to support the detection of areas where LF transmission is more likely to occur, and inform LF elimination efforts through better understanding of the environmental drivers.
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The dissemination of Escherichia coli producing extended-spectrum beta-lactamase (ESBL-Ec) is evident in the community. A population-based spatial analysis is necessary to investigate community risk factors for ESBL-Ec occurrence. The study population was defined as individuals with ESBL-Ec isolated in Queensland, Australia, from 2010 to 2019. Choropleth maps, global Moran's index and Getis-Ord Gi* were used to describe ESBL-Ec distribution and identify hot spots. Multivariable Poisson regression models with or without spatially structured random effects were performed. A total of 12 786 individuals with ESBL-Ec isolate were identified. The crude incidence rate increased annually from 9.1 per 100 000 residents in 2010 to 49.8 per 100 000 residents in 2019. The geographical distribution of ESBL-Ec changed from random to clustered after 2014, suggesting presence of community-specific factors that can enhance occurrence. Hot spots were more frequently identified in Outback and Far North Queensland, future public health measures to reduce transmission should prioritise these communities. Communities with higher socioeconomic status (RR = 0.66, 95% CI 0.55-0.79, per 100 units increase) and higher proportion of residents employed in the agricultural industry (RR = 0.79, 95% CI 0.67-0.95, per 10% increase) had lower ESBL-Ec incidence. Risk factors for occurrence appear differential between remote and city settings and this should be further investigated.
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Infecciones por Escherichia coli , Humanos , beta-Lactamasas , Escherichia coli , Incidencia , Queensland/epidemiología , Antibacterianos/uso terapéutico , Análisis EspacialRESUMEN
BACKGROUND: Under the Global Programme to Eliminate Lymphatic Filariasis (LF), American Samoa conducted 7 rounds of mass drug administration (MDA) between 2000 and 2006. The territory passed transmission assessment surveys (TASs) in 2011 (TAS-1) and 2015 (TAS-2). In 2016, the territory failed TAS-3, indicating resurgence. This study aims to determine if antibodies (Abs) may have provided a timelier indication of LF resurgence in American Samoa. METHODS: We examined school-level antigen (Ag) and Ab status (presence/absence of Ag- and Ab-positive children) and prevalence of single and combined Ab responses to Wb123, Bm14, and Bm33 Ags at each TAS. Pearson chi-square test and logistic regression were used to examine associations between school-level Ab prevalence in TAS-1 and TAS-2 and school-level Ag status in TAS-3. RESULTS: Schools with higher prevalence of Wb123 Ab in TAS-2 had higher odds of being Ag-positive in TAS-3 (odds ratio [OR] 24.5, 95% confidence interval [CI] 1.2-512.7). Schools that were Ab-positive for WB123 plus Bm14, Bm33, or both Bm14 and Bm33 in TAS-2 had higher odds of being Ag-positive in TAS-3 (OR 16.0-24.5). CONCLUSION: Abs could provide earlier signals of resurgence and enable a timelier response. The promising role of Abs in surveillance after MDA and decision making should be further investigated in other settings.
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Filariasis Linfática , Samoa Americana/epidemiología , Animales , Anticuerpos Antihelmínticos , Antígenos Helmínticos , Niño , Filariasis Linfática/tratamiento farmacológico , Filariasis Linfática/epidemiología , Filariasis Linfática/prevención & control , Humanos , Preparaciones Farmacéuticas , Wuchereria bancrofti/fisiologíaAsunto(s)
COVID-19 , Ejercicio Físico , Humanos , Pandemias/prevención & control , SARS-CoV-2 , Estudiantes de OdontologíaRESUMEN
INTRODUCTION: The increase in international travel brought about by globalisation has enabled the rapid spread of emerging pathogens with epidemic and pandemic potential. While travel connectivity-based assessments may help understand patterns of travel network-mediated epidemics, such approaches are rarely carried out in sufficient detail for Oceania where air travel is the dominant method of transportation between countries. DESIGN: Travel data from the Australian Bureau of Statistics, Stats NZ and the United Nations World Tourism Organization websites were used to calculate travel volumes in 2018 within Oceania and between Oceania and the rest of the world. The Infectious Disease Vulnerability Index (IDVI) was incorporated into the analysis as an indicator of each country's capacity to contain an outbreak. Travel networks were developed to assess the spread of infectious diseases (1) into and from Oceania, (2) within Oceania and (3) between each of the Pacific Island Countries and Territories (PICTs) and their most connected countries. RESULTS: Oceania was highly connected to countries in Asia, Europe and North America. Australia, New Zealand and several PICTs were highly connected to the USA and the UK (least vulnerable countries for outbreaks based on the IDVI), and to China (intermediate low vulnerable country). High variability was also observed between the PICTs in the geographical distribution of their international connections. The PICTs with the highest number of international connections were Fiji, French Polynesia, Guam and Papua New Guinea. CONCLUSION: Travel connectivity assessments may help to accurately stratify the risk of infectious disease importation and outbreaks in countries depending on disease transmission in other parts of the world. This information is essential to track future requirements for scaling up and targeting outbreak surveillance and control strategies in Oceania.
Asunto(s)
Viaje en Avión , Enfermedades Transmisibles , Australia/epidemiología , Enfermedades Transmisibles/epidemiología , Brotes de Enfermedades/prevención & control , Humanos , Pandemias , ViajeRESUMEN
Parasitic infections caused by Opisthorchis viverrini and Strongyloides stercoralis remain a major public health threat in the Greater Mekong Sub-region. An understanding of climate and other environmental influences on the geographical distribution and emergence of parasitic diseases is a crucial step to guide targeted control and prevention programs. A parasitological survey was conducted from 2008 to 2013 and included 12,554 individuals (age between 20 and 60 years) from 142 villages in five districts in Khon Kaen Province, Thailand. Geographical information systems, remote sensing technologies and a Bayesian geostatistical framework were used to develop models for O. viverrini and S. stercoralis mono- and co-infections in areas where both parasites are known to co-occur. The results indicate that male sex, increased age, altitude, precipitation, and land surface temperature have influenced the infection rate and geographical distribution of mono- and co-infections of O. viverrini and S. stercoralis in this area. Males were 6.69 times (95% CrI: 5.26-8.58) more likely to have O. viverrini - S. stercoralis co-infection. We observed that O. viverrini and S. stercoralis mono-infections display distinct spatial pattern, while co-infection is predicted in the center and southeast of the study area. The observed spatial clustering of O. viverrini and S. stercoralis provides valuable information for the spatial targeting of prevention interventions in this area.