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Seroprevalence studies on SARS-CoV-2 infections have been often based on study populations with non-random and non-representative samples, limiting the generalizability of their results. In this study, we investigated the representativity and the generalizability of the baseline (collected from October 16th, 2020, to April 18th, 2021) estimate of a pediatric seroprevalence study based in Montréal. We compared the change in the estimates of seroprevalence for two different weighting methods: marginal standardization and raking. The target population was the general pediatric population of Montréal and was based on 2016 Canadian census data. Study results show variation across the multiple weighting scenarios although both weighting methods performed similarly, each possessing its own strengths and weaknesses. However, we prefer raking due to its capacity to simultaneously weight for multiple underrepresented study population characteristics.
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The burden of maternal mortality in sub-Saharan Africa is the highest in the world. As high fertility rates present an increased risk to women's health, programmes and services have been put in place to increase access to family planning. Several studies have identified sociocultural factors as limiting access to family planning, including male resistance and women's low decision-making power. However, these studies have often used a behavioural approach that anchors barriers to access in women's attitudes or motivations. In 2019, a qualitative evaluation of a family planning programme using a behavioural approach was conducted in rural Uganda, focusing on women's attitudes and unmet needs. With hindsight, we realised that our evaluation was insufficient to adequately capture barriers that extend beyond women's motivations. This paper shares three case studies that we analysed using a structural health vulnerabilities approach. Our analysis highlights political, economic, social and cultural structures that can impede access to family planning. Using a structural health vulnerabilities approach, we identify structural barriers which have their roots in the local realities women face and propose context-specific structural recommendations. Finally, we contrast our initial results with findings the case studies presented to highlight the relevance of taking structural vulnerabilities into account in future family planning programme evaluation and women's sexual and reproductive health studies.
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Servicios de Planificación Familiar , Salud de la Mujer , Humanos , Masculino , Femenino , Uganda , Conducta SexualRESUMEN
The COVID-19 pandemic highlighted the impact of social inequalities in health (SIH). Various studies have shown significant inequalities in mortality and morbidity associated with COVID-19 and the influence of social determinants of health. The objective of this qualitative case study was to analyze the consideration of SIH in the design of two key COVID-19 prevention and control interventions in France: testing and contact tracing. Interviews were conducted with 36 key informants involved in the design of the intervention and/or the government response to the pandemic as well as relevant documents (n = 15) were reviewed. We applied data triangulation and a hybrid deductive and inductive analysis to analyze the data. Findings revealed the divergent understandings and perspectives about SIH, as well as the challenges associated with consideration for these at the beginning stages of the pandemic. Despite a shared concern for SIH between the participants, an epidemiological frame of reference dominated the design of the intervention. It resulted in a model in which consideration for SIH appeared as a complement, with a clinical goal of the intervention: breaking the chain of COVID-19 transmission. Although the COVID-19 health crisis highlighted the importance of SIH, it did not appear to be an opportunity to further their consideration in response efforts. This article provides original insights into consideration for SIH in the design of testing and contact-tracing interventions based upon a qualitative investigation.
The COVID-19 pandemic has highlighted the importance of social inequalities in health (SIH) and the disproportionate burden of the pandemic and its consequences related to socioeconomic status, ethnicity and race, among other determinants of health. Public health interventions are likely to increase SIH when they are not considered in the design phase. Through a qualitative case study, we analyzed the design of one of the first local initiative providing testing and contact tracing offer to the general population in the Île-de-France region (Paris region, France) in response to the COVID-19 pandemic. This article discusses the uncertainty and challenges associated with consideration for SIH in the intervention design. It explores the diverse understandings of SIH among the actors and the complexities of cross-sectoral partnerships addressing SIH in times of health crisis. Despite a consensual concern for this issue among the respondents, an epidemiological frame of reference dominated the intervention design. It resulted in a model in which consideration for SIH appeared as a complement, with a clinical goal of the intervention: breaking the chain of COVID-19 transmission.
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COVID-19 , Humanos , Pandemias/prevención & control , Francia/epidemiología , Factores SocioeconómicosRESUMEN
BACKGROUND: This study examines how the functioning of healthcare providers during the COVID-19 pandemic was affected by the government financing response, which was shaped by existing healthcare financing systems. METHODS: The study applied a single case study design at a tertiary hospital in Bamako during the 1st and 2nd waves of the COVID-19 pandemic. Data were gathered through 51 in-depth interviews with hospital staff, participatory observation, and reviewing media articles and hospital financial records. RESULTS: The study revealed the disruptions experienced by hospital managers, human resources for health and patients in Mali during the early stages of the pandemic. While the government aimed to support universal access to COVID-19-related services, efforts were undermined by issues associated with complex public financing management procedures. The hospital experienced long delays in transferring government funds. The hospital suffered a decrease in revenue during the early stages of the pandemic. Government budgets were not effectively used because of complex, non-agile procedures that could not adapt to the emergency. The challenges faced by the hospitals led to the delays in the staff payments of salaries and promised bonuses, which created potential for unfair treatment of patients. Excluding some COVID-19 related items from the government funded benefit package created a financial burden on people receiving services. The managerial challenges experienced in the study hospital during the first wave continued in the second wave. CONCLUSIONS: Pre-existent issues in healthcare financing and governance constrained the effective management of COVID-19-related services and created confusion at the front line of healthcare service delivery.
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COVID-19 , Pandemias , Humanos , Malí/epidemiología , Centros de Atención Terciaria , Atención a la SaludRESUMEN
BACKGROUND: The United Nations through universal health coverage, including sexual and reproductive health (SRH), pledges to include all people, leaving no one behind. However, people with disabilities continue to experience multiple barriers in accessing SRH services. Studies analysing the impacts of disability in conjunction with other social identities and health determinants reveal a complex pattern in SRH service use. Framed within a larger mixed methods study conducted in Uganda, we examined how disability, among other key social determinants of health (SDH), was associated with the use of SRH services. METHODS: We analysed data from repeated cross-sectional national surveys, the Uganda Demographic and Health Surveys (DHS) of 2006, 2011, and 2016. The three outcomes of interest were antenatal care visits, HIV testing, and modern contraception use. Our main exposure of interest was the type of disability, classified according to six functional dimensions: seeing, hearing, walking/climbing steps, remembering/concentrating, communicating, and self-care. We performed descriptive and multivariable logistic regression analyses, which controlled for covariates such as survey year, sex, age, place of residence, education, and wealth index. Interaction terms between disability and other factors such as sex, education, and wealth index were explored. Regression analyses were informed by an intersectionality framework to highlight social and health disparities within groups. RESULTS: From 2006 to 2016, 15.5-18.5% of study participants lived with some form of disability. Over the same period, the overall prevalence of at least four antenatal care visits increased from 48.3 to 61.0%, while overall HIV testing prevalence rose from 30.8 to 92.4% and the overall prevalence of modern contraception use increased from 18.6 to 34.2%. The DHS year, highest education level attained, and wealth index were the most consistent determinants of SRH service utilisation. People with different types of disabilities did not have the same SRH use patterns. Interactions between disability type and wealth index were associated with neither HIV testing nor the use of modern contraception. Women who were wealthy with hearing difficulty (Odds Ratio (OR) = 0.15, 95%CI 0.03 - 0.87) or with communication difficulty (OR = 0.17, 95%CI 0.03 - 0.82) had lower odds of having had optimal antenatal care visits compared to women without disabilities who were poorer. CONCLUSION: This study provided evidence that SRH service use prevalence increased over time in Uganda and highlights the importance of studying SRH and the different disability types when examining SDH. The SDH are pivotal to the attainment of universal health coverage, including SRH services, for all people irrespective of their social identities.
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Personas con Discapacidad , Servicios de Salud Reproductiva , Estudios Transversales , Demografía , Femenino , Encuestas Epidemiológicas , Humanos , Embarazo , Salud Reproductiva , Uganda/epidemiologíaRESUMEN
BACKGROUND: Evidence continues to demonstrate that certain marginalised populations are disproportionately affected by COVID-19. While many studies document the impacts of COVID-19 on social inequalities in health, none has examined how public health responses to the pandemic have unfolded to address these inequities in Canada. The purpose of our study was to assess how social inequalities in health were considered in the design and planning of large-scale COVID-19 testing programs in Montréal (Québec, Canada). METHODS: Part of the multicountry study HoSPiCOVID, this article reports on a qualitative case study of large-scale testing for COVID-19 in Montréal. We conducted semi-structured interviews with 19 stakeholders involved in planning large-scale testing or working with vulnerable populations during the pandemic. We developed interview guides and a codebook using existing literature on policy design and planning, and analysed data deductively and inductively using thematic analysis in NVivo. RESULTS: Our findings suggest that large-scale COVID-19 testing in Montréal did not initially consider social inequalities in health in its design and planning phases. Considering the sense of urgency brought by the pandemic, participants noted the challenges linked to the uptake of an intersectoral approach and of a unified vision of social inequalities in health. However, adaptations were gradually made to large-scale testing to improve its accessibility, acceptability, and availability. Actors from the community sector, among others, played an important role in supporting the health sector to address the needs of specific subgroups of the population. CONCLUSIONS: These findings contribute to the reflections on the lessons learned from COVID-19, highlighting that public health programs must tackle structural barriers to accessing healthcare services during health crises. This will be necessary to ensure that pandemic preparedness and response, including large-scale testing, do not further increase social inequalities in health.
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Prueba de COVID-19 , COVID-19 , COVID-19/epidemiología , Servicios de Salud , Humanos , Investigación Cualitativa , Factores SocioeconómicosRESUMEN
AIM: The objective of this research is to report the strategies of resilience mobilized by the Hospital of Mali to face Coronavirus disease (COVID-19). METHOD: The data collected within the hospital covered the first months of the pandemic (April to July 2020). A total of 32 semi-structured interviews and 53 observation sessions were conducted. Data analyses were based on a conceptual framework and were conducted using a deductive approach. RESULTS: The results show that, due to the multiple effects of the COVID-19 such as the aggravation of staff penuries, the high workloads, the need to create dedicated infrastructures, the drastic decrease in revenue due to the drop in hospital's attendance, the hospital and its staff implemented multiple strategies (e.g., reduction or postponement of some expenses, requisition of facilities, recruitment of contractual staff and redeployment of some healthcare workers). Those strategies generally allowed to maintain patients access to care, although there were many restrictions for non-COVID-19 patients. The hospital was able to build absorptive resilience. CONCLUSION: This qualitative research provides a better understanding of hospitals' resilience processes to the COVID-19 pandemic in a hospital setting. Lessons learned from this study should help hospitals managers to design more appropriate and effective responses to future health crises.
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COVID-19 , Pandemias , COVID-19/epidemiología , Hospitales , Humanos , Malí , SARS-CoV-2RESUMEN
Field studies have shown that dense tree canopies and regular tree arrangements reduce noise from a point source. In urban areas, noise sources are multiple and tree arrangements are rarely dense. There is a lack of data on the association between the urban tree canopy characteristics and noise in complex urban settings. Our aim was to investigate the spatial variation of urban tree canopy characteristics, indices of vegetation abundance, and environmental noise levels. Using Light Detection and Ranging point cloud data for 2015, we extracted the characteristics of 1,272,069 public and private trees across the island of Montreal, Canada. We distinguished needle-leaf from broadleaf trees, and calculated the percentage of broadleaf trees, the total area of the crown footprint, the mean crown centroid height, and the mean volume of crowns of trees that were located within 100m, 250m, 500m, and 1000m buffers around 87 in situ noise measurement sites. A random forest model incorporating tree characteristics, the normalized difference vegetation index (NDVI) values, and the distances to major urban noise sources (highways, railways and roads) was employed to estimate variation in noise among measurement locations. We found decreasing trends in noise levels with increases in total area of the crown footprint and mean crown centroid height. The percentages of increased mean squared error of the regression models indicated that in 500m buffers the total area of the crown footprint (29.2%) and the mean crown centroid height (12.6%) had a stronger influence than NDVI (3.2%) in modeling noise levels; similar patterns of influence were observed using other buffers. Our findings suggest that municipal initiatives designed to reduce urban noise should account for tree features, and not just the number of trees or the overall amount of vegetation.
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Hojas de la Planta , CanadáRESUMEN
OBJECTIVE: To examine the effect of an intervention combining user fees removal with community-based management of undernutrition on the nutrition status in children under 5 years of age in Burkina Faso. DESIGN: The study was a non-equivalent control group post-test-only design based on household survey data collected 4 years after the intervention onset in the intervention and comparison districts. Additionally, we used propensity score weighting to achieve balance on covariates between the two districts, followed by logistic multilevel modelling. SETTING: Two health districts in the Sahel region. PARTICIPANTS: Totally, 1116 children under 5 years of age residing in 41 intervention communities and 1305 from 51 control communities. RESULTS: When comparing children living in the intervention district to children living in a non-intervention district, we determined no differences in terms of stunting (OR = 1·13; 95 % CI 0·83, 1·54) and wasting (OR = 1·21; 95 % CI 0·90, 1·64), nor in severely wasted (OR = 1·27; 95 % CI 0·79, 2·04) and severely stunted (OR = 0·99; 95 % CI 0·76, 1·26). However, we determined that 3 % of the variance of wasting (95 % CI 1·25, 10·42) and 9·4 % of the variance of stunting (95 % CI 6·45, 13·38) were due to systematic differences between communities of residence. The presence of the intervention in the communities explained 2 % of the community-level variance of stunting and 3 % of the community-level variance of wasting. CONCLUSIONS: With the scaling-up of the national free health policy in Africa, we stress the need for rigorous evaluations and the means to measure expected changes in order to better inform health interventions.
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Desnutrición , Estado Nutricional , Burkina Faso/epidemiología , Niño , Preescolar , Trastornos del Crecimiento/epidemiología , Servicios de Salud , Humanos , Lactante , Desnutrición/epidemiologíaRESUMEN
BACKGROUND: Short birth interval is associated with adverse perinatal, maternal, and infant outcomes, although evidence on actionable factors underlying short birth interval remains limited. We explored women and community views on short birth intervals to inform potential solutions to promote a culturally safe child spacing in Northern Uganda. METHODS: Gendered fuzzy cognitive mapping sessions (n = 21), focus group discussions (n = 12), and an administered survey questionnaire (n = 255) generated evidence on short birth intervals. Deliberative dialogues with women, their communities, and service providers suggested locally relevant actions promote culturally safe child spacing. RESULTS: Women, men, and youth have clear understandings of the benefits of adequate child spacing. This knowledge is difficult to translate into practice as women are disempowered to exercise child spacing. Women who use contraceptives without their husbands' consent risk losing financial and social assets and are likely to be subject to intra-partner violence. Women were not comfortable with available contraceptive methods and reported experiencing well-recognized side effects. They reported anxiety about the impact of contraception on the health of their future children. This fear was fed by rumors in their communities about the effects of contraceptives on congenital diseases. The women and their communities suggested a home-based sensitization program focused on improving marital relationships (spousal communication, mutual understanding, male support, intra-partner violence) and knowledge and side-effects management of contraceptives. CONCLUSIONS: The economic context, gender power dynamics, inequality, gender bias in land tenure and ownership regulations, and the limited contraceptive supply reduce women's capacity to practice child spacing.
The evidence on what increases birth spacing remains limited. This study explored community views on influences on short birth interval to promote a culturally safe child spacing in Northern Uganda. A participatory research process began by collating perspectives of causes of short birth intervals through fuzzy cognitive mapping. Focus group discussions clarified concepts emerging from the fuzzy cognitive mapping exercise. Fieldworkers administered a household survey to quantify reproductive health outcomes. In deliberative dialogue sessions involving women and their communities, shared and discussed these results and suggested potential actions to promote culturally safe child spacing. Women, men, and youth showed clear understandings of the benefits of adequate child spacing. This knowledge is difficult to translate into practice, however, as women feel they are unable to exercise child spacing. Women who use contraceptives without their husbands' consent risk losing financial and social resources and are likely to face intra-partner violence. Women were not comfortable with contraceptive methods and reported experiencing side effects. The deliberative dialogues suggested a home-based sensitization program focused on improving marital relationships (spousal communication, mutual understanding, male support, intra-partner violence) and knowledge and side-effects management of contraceptives.
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Intervalo entre Nacimientos , Conducta Anticonceptiva , Anticoncepción/estadística & datos numéricos , Adolescente , Adulto , Niño , Investigación Participativa Basada en la Comunidad , Femenino , Teoría Fundamentada , Humanos , Masculino , Matrimonio , Edad Materna , Embarazo , Salud Reproductiva , Sexismo , Normas Sociales , UgandaRESUMEN
BACKGROUND: As Canadian global health researchers who conducted a qualitative study with adults with and without disabilities in Uganda, we obtained ethics approval from four institutional research ethics boards (two in Canada and two in Uganda). In Canada, research ethics boards and researchers follow the research ethics norms of the Tri-Council Policy Statement: Ethical Conduct for Research Involving Humans (TCPS2), and the National Guidelines for Research Involving Humans as Research Participants of Uganda (NGRU) in Uganda. The preparation and implementation of this qualitative research raised specific ethical issues related to research participant privacy and the importance of availability and management of financial resources. MAIN BODY: Our field experience highlights three main issues for reflection. First, we demonstrate that, in a global health research context, methodological and logistic adjustments were necessary throughout the research implementation process to ensure the protection of study participants' privacy, especially that of people with disabilities, despite having followed the prescribed Canadian and Ugandan ethics norms. Data collection and management plans were adapted iteratively based on local realities. Second, securing financial support as a key aspect of financial management was critical to ensure privacy through disability-sensitive data collection strategies. Without adequate funding, the recruitment of research participants based on disability type, sex, and region or the hiring of local sign language interpreters would not have been possible. Third, although the TCPS2 and NGRU underscore the significance of participants' privacy, none of these normative documents clearly express this issue in the context of global health research and disability, nor broadly discuss the ethical issue related to financial availability and management. CONCLUSIONS: Conducting research in resource limited settings and with study participants with different needs calls for a nuanced and respectful implementation of research ethics in a global health context. We recommend a greater integration in both the TCPS2 and NGRU of global health research, disability, and responsible conduct of research. This integration should also be accompanied by adequate training which can further guide researchers, be they senior, junior, or students, and funding agencies.
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Personas con Discapacidad , Salud Global , Canadá , Humanos , Investigación Cualitativa , UgandaRESUMEN
BACKGROUND: All prevention efforts currently being implemented for COVID-19 are aimed at reducing the burden on strained health systems and human resources. There has been little research conducted to understand how SARS-CoV-2 has affected health care systems and professionals in terms of their work. Finding effective ways to share the knowledge and insight between countries, including lessons learned, is paramount to the international containment and management of the COVID-19 pandemic. The aim of this project is to compare the pandemic response to COVID-19 in Brazil, Canada, China, France, Japan, and Mali. This comparison will be used to identify strengths and weaknesses in the response, including challenges for health professionals and health systems. METHODS: We will use a multiple case study approach with multiple levels of nested analysis. We have chosen these countries as they represent different continents and different stages of the pandemic. We will focus on several major hospitals and two public health interventions (contact tracing and testing). It will employ a multidisciplinary research approach that will use qualitative data through observations, document analysis, and interviews, as well as quantitative data based on disease surveillance data and other publicly available data. Given that the methodological approaches of the project will be largely qualitative, the ethical risks are minimal. For the quantitative component, the data being used will be made publicly available. DISCUSSION: We will deliver lessons learned based on a rigorous process and on strong evidence to enable operational-level insight for national and international stakeholders.
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COVID-19 , Pandemias , Brasil , Canadá , China , Francia , Hospitales , Humanos , Japón , Malí , Pandemias/prevención & control , Salud Pública , SARS-CoV-2RESUMEN
BACKGROUND: Indoor residual spraying (IRS) is widely used as a vector control measure, although there are conflicting findings of its effectiveness in reducing malaria incidence. The objective of this study was to estimate the effect of multiple IRS rounds on malaria incidence and hemoglobin levels in a cohort of children in rural southeastern Uganda. METHODS: The study was based upon a dynamic cohort of children aged 0.5-10 years enrolled from August 2011 to June 2017 in Nagongera Subcounty. Confirmed malaria infections and hemoglobin levels were recorded over time for each participant. After each of 4 rounds of IRS, malaria incidence, hemoglobin levels, and parasite density were evaluated and compared with pre-IRS levels. Analyses were carried out at the participant level while accounting for repeated measures and clustering by household. RESULTS: Incidence rate ratios comparing post-IRS to pre-IRS incidence rates for age groups 0-3, 3-5, and 5-11 were 0.108 (95% confidence interval [CI], .078-.149), 0.173 (95% CI, .136-.222), and 0.226 (95% CI, .187-.274), respectively. The mean hemoglobin levels significantly increased from 11.01 (pre-IRS) to 12.18 g/dL (post-IRS). CONCLUSIONS: Our study supports the policy recommendation of IRS usage in a stable and perennial transmission area to rapidly reduce malaria transmission.
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Hemoglobinas/análisis , Insecticidas/administración & dosificación , Malaria/epidemiología , Organofosfonatos/administración & dosificación , Fenilcarbamatos/administración & dosificación , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Incidencia , Lactante , Malaria/prevención & control , Malaria/transmisión , Masculino , Control de Mosquitos/métodos , Parasitemia/epidemiología , Uganda/epidemiologíaRESUMEN
Objectives Increasing financial access to healthcare is proposed to being essential for improving child health outcomes, but the available evidence on the relationship between increased access and health remains scarce. Four years after its launch, we evaluated the contextual effect of user fee removal intervention on the probability of an illness occurring and the likelihood of using health services among children under 5. We also explored the potential effect on the inequality in healthcare access. Methods We used a comparative cross-sectional design based upon household survey data collected years after the intervention onset in one intervention and one comparison district. Propensity scores weighting was used to achieve balance on covariates between the two districts, which was followed by logistic multilevel modelling to estimate average marginal effects (AME). Results We estimated that there was not a significant difference in the reduced probability of an illness occurring in the intervention district compared to the non-intervention district [AME 4.4; 95% CI 1.0-9.8)]. However, the probability of using health services was 17.2% (95% CI 15.0-26.6) higher among children living in the intervention district relative to the comparison district, which rose to 20.7% (95% CI 9.9-31.5) for severe illness episodes. We detected no significant differences in the probability of health services use according to socio-economic status [χ2 (5) = 12.90, p = 0.61]. Conclusions for Practice In our study, we found that user fee removal led to a significant increase in the use of health services in the longer term, but it is not adequate by itself to reduce the risk of illness occurrence and socioeconomic inequities in the use of health services.
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Servicios de Salud del Niño/estadística & datos numéricos , Honorarios y Precios , Accesibilidad a los Servicios de Salud/economía , Servicios de Salud/estadística & datos numéricos , Disparidades en Atención de Salud , Población Rural , Burkina Faso , Niño , Servicios de Salud del Niño/economía , Preescolar , Estudios Transversales , Femenino , Gastos en Salud , Política de Salud , Servicios de Salud/economía , Accesibilidad a los Servicios de Salud/legislación & jurisprudencia , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Humanos , Masculino , Aceptación de la Atención de Salud , Embarazo , Factores SocioeconómicosRESUMEN
BACKGROUND: Malaria transmission is driven by multiple factors, including complex and multifaceted connections between malaria transmission, socioeconomic conditions, climate and interventions. Forecasting models should account for all significant drivers of malaria incidence although it is first necessary to understand the relationship between malaria burden and the various determinants of risk to inform the development of forecasting models. In this study, the associations between malaria risk, environmental factors, and interventions were evaluated through a systematic review. METHODS: Five electronic databases (CAB Abstracts, EMBASE, Global Health, MEDLINE and ProQuest Dissertations & Theses) were searched for studies that included both the effects of the environment and interventions on malaria within the same statistical model. Studies were restricted to quantitative analyses and health outcomes of malaria mortality or morbidity, outbreaks, or transmission suitability. Meta-analyses were conducted on a subset of results using random-effects models. RESULTS: Eleven studies of 2248 potentially relevant articles that met inclusion criteria were identified for the systematic review and two meta-analyses based upon five results each were performed. Normalized Difference Vegetation Index was not found to be statistically significant associated with malaria with a pooled OR of 1.10 (95% CI 0.07, 1.71). Bed net ownership was statistically associated with decreasing risk of malaria, when controlling for the effects of environment with a pooled OR of 0.75 (95% CI 0.60, 0.95). In general, environmental effects on malaria, while controlling for the effect of interventions, were variable and showed no particular pattern. Bed nets ownership, use and distribution, have a significant protective effect while controlling for environmental variables. CONCLUSIONS: There are a limited number of studies which have simultaneously evaluated both environmental and interventional effects on malaria risk. Poor statistical reporting and a lack of common metrics were important challenges for this review, which must be addressed to ensure reproducibility and quality research. A comprehensive or inclusive approach to identifying malaria determinants using standardized indicators would allow for a better understanding of its epidemiology, which is crucial to improve future malaria risk estimations.
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Control de Enfermedades Transmisibles/métodos , Ambiente , Malaria/epidemiología , Riesgo , HumanosRESUMEN
We estimated the speed of Zika virus introduction in Brazil by using confirmed cases at the municipal level. Our models indicate a southward pattern of introduction starting from the northeastern coast and a pattern of movement toward the western border with an average speed of spread of 42 km/day or 15,367 km/year.
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Brotes de Enfermedades , Modelos Estadísticos , Infección por el Virus Zika/epidemiología , Infección por el Virus Zika/transmisión , Virus Zika/fisiología , Brasil/epidemiología , Monitoreo Epidemiológico , Humanos , Incidencia , Estaciones del Año , Virus Zika/patogenicidad , Infección por el Virus Zika/virologíaRESUMEN
BACKGROUND: Long-lasting insecticidal nets (LLINs) and indoor residual spraying of insecticide (IRS) are the primary vector control interventions used to prevent malaria in Africa. Although both interventions are effective in some settings, high-quality evidence is rarely available to evaluate their effectiveness following deployment by a national malaria control program. In Uganda, we measured changes in key malaria indicators following universal LLIN distribution in three sites, with the addition of IRS at one of these sites. METHODS AND FINDINGS: Comprehensive malaria surveillance was conducted from October 1, 2011, to March 31, 2016, in three sub-counties with relatively low (Walukuba), moderate (Kihihi), and high transmission (Nagongera). Between 2013 and 2014, universal LLIN distribution campaigns were conducted in all sites, and in December 2014, IRS with the carbamate bendiocarb was initiated in Nagongera. High-quality surveillance evaluated malaria metrics and mosquito exposure before and after interventions through (a) enhanced health-facility-based surveillance to estimate malaria test positivity rate (TPR), expressed as the number testing positive for malaria/number tested for malaria (number of children tested for malaria: Walukuba = 42,833, Kihihi = 28,790, and Nagongera = 38,690); (b) cohort studies to estimate the incidence of malaria, expressed as the number of episodes per person-year [PPY] at risk (number of children observed: Walukuba = 340, Kihihi = 380, and Nagongera = 361); and (c) entomology surveys to estimate household-level human biting rate (HBR), expressed as the number of female Anopheles mosquitoes collected per house-night of collection (number of households observed: Walukuba = 117, Kihihi = 107, and Nagongera = 107). The LLIN distribution campaign substantially increased LLIN coverage levels at the three sites to between 65.0% and 95.5% of households with at least one LLIN. In Walukuba, over the 28-mo post-intervention period, universal LLIN distribution was associated with no change in the incidence of malaria (0.39 episodes PPY pre-intervention versus 0.20 post-intervention; adjusted rate ratio [aRR] = 1.02, 95% CI 0.36-2.91, p = 0.97) and non-significant reductions in the TPR (26.5% pre-intervention versus 26.2% post-intervention; aRR = 0.70, 95% CI 0.46-1.06, p = 0.09) and HBR (1.07 mosquitoes per house-night pre-intervention versus 0.71 post-intervention; aRR = 0.41, 95% CI 0.14-1.18, p = 0.10). In Kihihi, over the 21-mo post-intervention period, universal LLIN distribution was associated with a reduction in the incidence of malaria (1.77 pre-intervention versus 1.89 post-intervention; aRR = 0.65, 95% CI 0.43-0.98, p = 0.04) but no significant change in the TPR (49.3% pre-intervention versus 45.9% post-intervention; aRR = 0.83, 95% 0.58-1.18, p = 0.30) or HBR (4.06 pre-intervention versus 2.44 post-intervention; aRR = 0.71, 95% CI 0.30-1.64, p = 0.40). In Nagongera, over the 12-mo post-intervention period, universal LLIN distribution was associated with a reduction in the TPR (45.3% pre-intervention versus 36.5% post-intervention; aRR = 0.82, 95% CI 0.76-0.88, p < 0.001) but no significant change in the incidence of malaria (2.82 pre-intervention versus 3.28 post-intervention; aRR = 1.10, 95% 0.76-1.59, p = 0.60) or HBR (41.04 pre-intervention versus 20.15 post-intervention; aRR = 0.87, 95% CI 0.31-2.47, p = 0.80). The addition of three rounds of IRS at ~6-mo intervals in Nagongera was followed by clear decreases in all outcomes: incidence of malaria (3.25 pre-intervention versus 0.63 post-intervention; aRR = 0.13, 95% CI 0.07-0.27, p < 0.001), TPR (37.8% pre-intervention versus 15.0% post-intervention; aRR = 0.54, 95% CI 0.49-0.60, p < 0.001), and HBR (18.71 pre-intervention versus 3.23 post-intervention; aRR = 0.29, 95% CI 0.17-0.50, p < 0.001). High levels of pyrethroid resistance were documented at all three study sites. Limitations of the study included the observational study design, the lack of contemporaneous control groups, and that the interventions were implemented under programmatic conditions. CONCLUSIONS: Universal distribution of LLINs at three sites with varying transmission intensity was associated with modest declines in the burden of malaria for some indicators, but the addition of IRS at the highest transmission site was associated with a marked decline in the burden of malaria for all indicators. In highly endemic areas of Africa with widespread pyrethroid resistance, IRS using alternative insecticide formulations may be needed to achieve substantial gains in malaria control.
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Mosquiteros Tratados con Insecticida/estadística & datos numéricos , Insecticidas , Malaria/epidemiología , Control de Mosquitos , Vigilancia de la Población , Niño , Preescolar , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Incidencia , Lactante , Malaria/parasitología , Malaria/prevención & control , Malaria/transmisión , Masculino , Estudios Prospectivos , Uganda/epidemiologíaRESUMEN
BACKGROUND: Environmental factors play a major role in transmission of malaria given their relationship to both the development and survival of the mosquito and parasite. The associations between environmental factors and malaria can be used to inform the development of early warning systems for increases in malaria burden. The objective of this study was to assess temporal relationships between rainfall, temperature and vegetation with malaria morbidity across three different transmission settings in Uganda. METHODS: Temporal relationships between environmental factors (weekly total rainfall, mean day time temperature and enhanced vegetation index series) and malaria morbidity (weekly malaria case count data and test positivity rate series) over the period January 2010-May 2013 in three sites located in varying malaria transmission settings in Uganda was explored using cross-correlation with pre-whitening. Sites included Kamwezi (low transmission), Kasambya (moderate transmission) and Nagongera (high transmission). RESULTS: Nagongera received the most rain (30.6 mm) and experienced, on average, the highest daytime temperatures (29.8 °C) per week. In the study period, weekly TPR and number of malaria cases were highest at Kasambya and lowest at Kamwezi. The largest cross-correlation coefficients between environmental factors and malaria morbidity for each site was 0.27 for Kamwezi (rainfall and cases), 0.21 for Kasambya (vegetation and TPR), and -0.27 for Nagongera (daytime temperature and TPR). Temporal associations between environmental factors (rainfall, temperature and vegetation) with malaria morbidity (number of malaria cases and TPR) varied by transmission setting. Longer time lags were observed at Kamwezi and Kasambya compared to Nagongera in the relationship between rainfall and number of malaria cases. Comparable time lags were observed at Kasambya and Nagongera in the relationship between temperature and malaria morbidity. Temporal analysis of vegetation with malaria morbidity revealed longer lags at Kasambya compared to those observed at the other two sites. CONCLUSIONS: This study showed that temporal associations between environmental factors with malaria morbidity vary by transmission setting in Uganda. This suggests the need to incorporate local transmission differences when developing malaria early warning systems that have environmental predictors in Uganda. This will result in development of more accurate early warning systems, which are a prerequisite for effective malaria control in such a setting.
Asunto(s)
Clima , Ambiente , Malaria/epidemiología , Desarrollo de la Planta , Humanos , Lluvia , Análisis Espacio-Temporal , Temperatura , Uganda/epidemiologíaRESUMEN
BACKGROUND: Malaria thrives in poor tropical and subtropical countries where local resources are limited. Accurate disease forecasts can provide public and clinical health services with the information needed to implement targeted approaches for malaria control that make effective use of limited resources. The objective of this study was to determine the relevance of environmental and clinical predictors of malaria across different settings in Uganda. METHODS: Forecasting models were based on health facility data collected by the Uganda Malaria Surveillance Project and satellite-derived rainfall, temperature, and vegetation estimates from 2006 to 2013. Facility-specific forecasting models of confirmed malaria were developed using multivariate autoregressive integrated moving average models and produced weekly forecast horizons over a 52-week forecasting period. RESULTS: The model with the most accurate forecasts varied by site and by forecast horizon. Clinical predictors were retained in the models with the highest predictive power for all facility sites. The average error over the 52 forecasting horizons ranged from 26 to 128% whereas the cumulative burden forecast error ranged from 2 to 22%. CONCLUSIONS: Clinical data, such as drug treatment, could be used to improve the accuracy of malaria predictions in endemic settings when coupled with environmental predictors. Further exploration of malaria forecasting is necessary to improve its accuracy and value in practice, including examining other environmental and intervention predictors, including insecticide-treated nets.