Spatiotemporal Analysis of Serogroup C Meningococcal Meningitis Spread in Niger and Nigeria and Implications for Epidemic Response

Abstract Background After the re-emergence of serogroup C meningococcal meningitis (MM) in Nigeria and Niger, we aimed to re-evaluate the vaccination policy used to respond to outbreaks of MM in the African meningitis belt by investigating alternative strategies using a lower incidence threshold and information about neighboring districts. Methods We used data on suspected and laboratory-confirmed cases in Niger and Nigeria from 2013 to 2017. We calculated global and local Moran’s I-statistics to identify spatial clustering of districts with high MM incidence. We used a Pinner model to estimate the impact of vaccination campaigns occurring between 2015 and 2017 and to evaluate the impact of 3 alternative district-level vaccination strategies, compared with that currently used. Results We found significant clustering of high incidence districts in every year, with local clusters around Tambuwal, Nigeria in 2013 and 2014, Niamey, Niger in 2016, and in Sokoto and Zamfara States in Nigeria in 2017. We estimate that the vaccination campaigns implemented in 2015, 2016, and 2017 prevented 6% of MM cases. Using the current strategy but with high coverage (85%) and timely distribution (4 weeks), these campaigns could have prevented 10% of cases. This strategy required the fewest doses of vaccine to prevent a case. None of the alternative strategies we evaluated were more efficient, but they would have prevented the occurrence of more cases overall. Conclusions Although we observed significant spatial clustering in MM in Nigeria and Niger between 2013 and 2017, there is no strong evidence to support a change in methods for epidemic response in terms of lowering the intervention threshold or targeting neighboring districts for reactive vaccination.

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Impacts of Physical Environment Perception on the Frailty Condition in Older People

Geospatial health ◽

10.4081/gh.2020.888 ◽

2020 ◽

Vol 15 (1) ◽

Author(s):

Carlos Mena ◽

Yony Ormazabal ◽

Eduardo Fuentes ◽

Iván Palomo

Keyword(s):

Older People ◽

Physical Environment ◽

Spatial Clustering ◽

Physical Environments ◽

Geographic Clustering ◽

Environment Perception ◽

Global And Local ◽

The Impact ◽

The City

Frailty increases the vulnerability of older people who commonly develop a syndrome leading to growing dependence and finally often death. Physical environment conditions may affect the severity of the syndrome positive or negatively. The main objective of this study was to analyse the conditions of different urban physical environments and their relationship with the frailty syndrome in older people. Geographic Information Systems (GIS) analyses were performed to detect global and local geographic clustering. Investigating 284 adults with ages from 60 to 74 years old from Talca City, Chile, we found spatial clustering of frailty conditions registered for older people, with hotspots of high and low values associated with areas of different urban infrastructures and socioeconomic levels into the city. The spatial identifications found should facilitate exploring the impact of mental health programmes in communities exposed to disasters like earthquakes, thereby improving their quality of life as well as reducing overall costs. Spatial correlation has a great potential for studying frailty conditions in older people with regard to better understanding the impact of environmental conditions on health.

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Impact of vaccination on the incidence of measles in Mozambique in the period 2000 to 2011

Cadernos de Saúde Pública ◽

10.1590/s0102-311x2013000200013 ◽

2013 ◽

Vol 29 (2) ◽

pp. 257-269 ◽

Cited By ~ 2

Author(s):

Artur Manuel Muloliwa ◽

Luiz Antonio Bastos Camacho ◽

José Fernando Souza Verani ◽

Taynãna César Simões ◽

Martinho do Carmo Dgedge

Keyword(s):

Vaccine Coverage ◽

Incidence Rates ◽

Measles Elimination ◽

High Incidence ◽

Maputo City ◽

Measles Vaccination ◽

Coverage Rates ◽

Vaccination Campaigns ◽

Measles Incidence ◽

The Impact

The aim of this study was to contribute to the better planning of measles elimination actions in Mozambique, by considering the impact of vaccination actions over the period 2000 to 2011. Descriptive and ecological studies and case records made available by the Ministry of Health were used to analyze measles vaccination coverage. Statistical analysis was performed using time series and spatial analysis. Vaccine coverage rates ranged from 82% to 99%. Coverage rates in Maputo city were under 70% and in Niassa province they were over 100%. Coverage showed a clustered pattern in the districts. The measles incidence rate was 1.58 per 100,000 inhabitants (0.00-40.08 per 100,000 inhabitants); districts bordering neighboring countries presented high incidence rates. Although measles morbidity and mortality has decreased in Mozambique, vaccine coverage has been insufficient to interrupt measles transmission. Enhanced surveillance, including investigation of cases and outbreaks, and improvements in measles vaccination are recommended in order to achieve a homogenous coverage rate of ≥ 95% for both routine and mass vaccination campaigns.

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Spatial Clustering of Pedestrian Activity and the Built Environment Characteristics

Nano LIFE ◽

10.1142/s1793984418400056 ◽

2018 ◽

Vol 08 (02) ◽

pp. 1840005

Author(s):

Hao Zhang ◽

Li Yin

Keyword(s):

New York ◽

Built Environment ◽

Spatial Patterns ◽

Goodness Of Fit ◽

Spatial Clustering ◽

Poisson Model ◽

Urban Revitalization ◽

Policy Makers ◽

Global And Local ◽

The Impact

Promoting pedestrian activity has attracted increasing attention as an important strategy for the improvement of public health and urban revitalization. The impact on physical activity underpinned by built environment has been studied substantially; however, few studies had focused on the geographically varying relationships between pedestrian activity and the built environment characteristics. Built upon previous work, this study looks at the spatial patterns of pedestrian counts and the built environment contributors along two major streets in Buffalo, New York using global and local spatial autocorrelation tests and geographically weighted regression. Pedestrian generators, job density and land use mix are included as independent variables in order to study the impact on them due to the characteristics of built environment. Our findings suggest that (1) there are statistically significant clusters of street intersections with high pedestrian counts along the streets selected in our study; (2) there are some optimal sizes of clusters of pedestrian generators, which attract more pedestrians; (3) geographically weighted Poisson model helps to analyze the geographically varying relationships between the built environment and pedestrian activity with a more pronounced goodness of fit. This research contributes to the understanding of the spatial patterns of pedestrian activity and the geographically varying relationship between the built environment and pedestrian counts. Hopefully this research will help to guide and focus the minds of policy makers and urban planners alike to introduce street vitality through the modifications of the built environment, so as to improve the quality of life in their neighborhoods.

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Phenylketonuria incidence in China between 2013 and 2017 based on data from the Chinese newborn screening information system: a descriptive study

BMJ Open ◽

10.1136/bmjopen-2019-031474 ◽

2019 ◽

Vol 9 (8) ◽

pp. e031474 ◽

Cited By ~ 3

Author(s):

Liangcheng Xiang ◽

Jing Tao ◽

Kui Deng ◽

Xiaohong Li ◽

Qi Li ◽

...

Keyword(s):

Information System ◽

Newborn Screening ◽

Spatial Autocorrelation ◽

Spatial Clustering ◽

Mild Disease ◽

System A ◽

High Incidence ◽

Global And Local ◽

Global Moran’S I ◽

Local Spatial Autocorrelation

ObjectiveThis study examines the incidence and spatial clustering of phenylketonuria (PKU) in China between 2013 and 2017.MethodsData from the Chinese Newborn Screening Information System were analysed to assess PKU incidence with 95% CIs by province, region and disease severity. Spatial clustering of PKU cases was analysed using global and local spatial autocorrelation analysis in the geographic information system.ResultsThe database contained 4925 neonates with confirmed PKU during the study period, corresponding to an incidence of 6.28 (95% CI: 6.11 to 6.46) per 100 000 neonates screened. Incidence was highest in the provinces of Gansu, Ningxia and Qinghai, where it ranged from 19.00 to 28.63 per 100 000 neonates screened. Overall incidence was higher in the northern part of the country, where classical disease predominated, than in the southern part, where mild disease predominated. PKU cases clustered spatially (global Moran’s I=0.3603,Z=5.3097, p<0.001), and local spatial autocorrelation identified four northern provinces as high–high clusters (Gansu, Qinghai, Ningxia and Shanxi).ConclusionsChina shows an intermediate PKU incidence among countries, and incidence differs substantially among Chinese provinces and between northern and southern regions. Our results suggest the need to focus efforts on screening, diagnosing and treating PKU in high-incidence provinces.

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Potential impact of spatially targeted adult tuberculosis vaccine in Gujarat, India

Journal of The Royal Society Interface ◽

10.1098/rsif.2015.1016 ◽

2016 ◽

Vol 13 (116) ◽

pp. 20151016 ◽

Cited By ~ 7

Author(s):

Sourya Shrestha ◽

Susmita Chatterjee ◽

Krishna D. Rao ◽

David W. Dowdy

Keyword(s):

General Population ◽

Spatial Heterogeneity ◽

Vaccine Delivery ◽

Population Level ◽

Accurate Estimation ◽

High Coverage ◽

High Incidence ◽

Delivery Strategies ◽

Childhood Vaccines ◽

The Impact

Some of the most promising vaccines in the pipeline for tuberculosis (TB) target adolescents and adults. Unlike for childhood vaccines, high-coverage population-wide vaccination is significantly more challenging for adult vaccines. Here, we aimed to estimate the impact of vaccine delivery strategies that were targeted to high-incidence geographical ‘hotspots’ compared with randomly allocated vaccination. We developed a spatially explicit mathematical model of TB transmission that distinguished these hotspots from the general population. We evaluated the impact of targeted and untargeted vaccine delivery strategies in India—a country that bears more than 25% of global TB burden, and may be a potential early adopter of the vaccine. We collected TB notification data and conducted a demonstration study in the state of Gujarat to validate our estimates of heterogeneity in TB incidence. We then projected the impact of randomly vaccinating 8% of adults in a single mass campaign to a spatially targeted vaccination preferentially delivered to 80% of adults in the hotspots, with both strategies augmented by continuous adolescent vaccination. In consultation with vaccine developers, we considered a vaccine efficacy of 60%, and evaluated the population-level impact after 10 years of vaccination. Spatial heterogeneity in TB notification (per 100 000/year) was modest in Gujarat: 190 in the hotspots versus 125 in the remaining population. At this level of heterogeneity, the spatially targeted vaccination was projected to reduce TB incidence by 28% after 10 years, compared with a 24% reduction projected to achieve via untargeted vaccination—a 1.17-fold augmentation in the impact of vaccination by spatially targeting. The degree of the augmentation was robust to reasonable variation in natural history assumptions, but depended strongly on the extent of spatial heterogeneity and mixing between the hotspot and general population. Identifying high-incidence hotspots and quantifying spatial mixing patterns are critical to accurate estimation of the value of targeted intervention strategies.

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A Spatiotemporal Analysis of Socio-Environmental Patterns in Severe Maternal Morbidity: A Retrospective Birth Cohort

10.1101/2021.03.16.21253540 ◽

2021 ◽

Author(s):

Stella Harden ◽

Jennifer D Runkle ◽

Margaret Mae Sugg

Keyword(s):

Risk Factors ◽

South Carolina ◽

High Risk ◽

Maternal Morbidity ◽

Spatial Clustering ◽

Spatiotemporal Analysis ◽

Severe Maternal Morbidity ◽

Spatial Scan Statistic ◽

Black Patients ◽

The Impact

Objectives. Severe Maternal Morbidity (SMM) is a group of pregnancy complications in which a woman nearly dies. Despite its increasing prevalence, there is little research that evaluates geographic patterns of SMM and the underlying social determinants that influence excess risk. This study examines the spatial clustering of SMM across South Carolina, US, and its associations with place-based social and environmental factors. Methods. Hospitalized deliveries from 1999 to 2017 were analyzed using Kulldorff's spatial scan statistic to locate areas with abnormally high rates of SMM. Patients inside and outside risk clusters were compared using Generalized Estimating Equations (GEE) to determine underlying risk factors. Results. Final models revealed that the odds of living in a high-risk cluster were 84% higher among Black patients (OR=1.84, p<.001), 30% higher among Hispanic and Latina patients (OR=1.3, p<.05), and 1.51 times more likely among women living in highly segregated and poorer minority communities (OR=1.51 p<.001). Odds for residing in a high-risk cluster were 23% higher for those who gave birth during a period with temperatures above 30.65C/87.3F (OR=1.23, p<.001). Conclusions. This study is the first to characterize the geographic clustering of SMM risk in the US. Our geospatial approach contributes a novel understanding to factors which influence SMM beyond patient-level characteristics and identifies the impact of systemic racism on maternal morbidity. Findings address an important literature gap surrounding place-based risk factors by explaining the contextual social and built environment variables that drive SMM risk.

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Spatiotemporal analysis of COVID-19 outbreaks in Wuhan, China

Scientific Reports ◽

10.1038/s41598-021-93020-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Wei Liu ◽

Dongming Wang ◽

Shuiqiong Hua ◽

Cong Xie ◽

Bin Wang ◽

...

Keyword(s):

Population Density ◽

Disease Surveillance ◽

Influence Factors ◽

Spatiotemporal Analysis ◽

Disease Surveillance System ◽

Local Aggregation ◽

Short Time ◽

Effective Public Health ◽

Global And Local ◽

Spatial Transmission

AbstractFew study has revealed spatial transmission characteristics of COVID-19 in Wuhan, China. We aimed to analyze the spatiotemporal spread of COVID-19 in Wuhan and its influence factors. Information of 32,682 COVID-19 cases reported through March 18 were extracted from the national infectious disease surveillance system. Geographic information system methods were applied to analysis transmission of COVID-19 and its influence factors in different periods. We found decrease in effective reproduction number (Rt) and COVID-19 related indicators through taking a series of effective public health measures including restricting traffic, centralized quarantine and strict stay-at home policy. The distribution of COVID-19 cases number in Wuhan showed obvious global aggregation and local aggregation. In addition, the analysis at streets-level suggested population density and the number of hospitals were associated with COVID-19 cases number. The epidemic situation showed obvious global and local spatial aggregations. High population density with larger number of hospitals may account for the aggregations. The epidemic in Wuhan was under control in a short time after strong quarantine measures and restrictions on movement of residents were implanted.

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The Impact of Ultraviolet Radiation on the Aetiology and Development of Uveal Melanoma

Cancers ◽

10.3390/cancers13071700 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1700

Author(s):

Melissa Chalada ◽

Charmaine A. Ramlogan-Steel ◽

Bijay P. Dhungel ◽

Christopher J. Layton ◽

Jason C. Steel

Keyword(s):

Risk Factors ◽

Ultraviolet Radiation ◽

Uveal Melanoma ◽

World Health Organisation ◽

World Health ◽

Genetic Mutations ◽

High Incidence ◽

The World ◽

The Impact

Uveal melanoma (UM) is currently classified by the World Health Organisation as a melanoma caused by risk factors other than cumulative solar damage. However, factors relating to ultraviolet radiation (UVR) susceptibility such as light-coloured skin and eyes, propensity to burn, and proximity to the equator, frequently correlate with higher risk of UM. These risk factors echo those of the far more common cutaneous melanoma (CM), which is widely accepted to be caused by excessive UVR exposure, suggesting a role of UVR in the development and progression of a proportion of UM. Indeed, this could mean that countries, such as Australia, with high UVR exposure and the highest incidences of CM would represent a similarly high incidence of UM if UVR exposure is truly involved. Most cases of UM lack the typical genetic mutations that are related to UVR damage, although recent evidence in a small minority of cases has shown otherwise. This review therefore reassesses statistical, environmental, anatomical, and physiological evidence for and against the role of UVR in the aetiology of UM.

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Prostate cancer and the human papilloma virus: causative association, role of vaccines, and the impact of the COVID-19 pandemic

Prostate Cancer and Prostatic Diseases ◽

10.1038/s41391-021-00404-6 ◽

2021 ◽

Author(s):

Naomi Morka ◽

Joseph M. Norris ◽

Mark Emberton ◽

Daniel Kelly

Keyword(s):

Prostate Cancer ◽

Human Papilloma Virus ◽

Hpv Vaccination ◽

Significant Proportion ◽

Vaccine Uptake ◽

Papilloma Virus ◽

Vaccination Campaigns ◽

The Impact ◽

Hpv Vaccine Uptake

AbstractProstate cancer affects a significant proportion of men worldwide. Evidence from genetic and clinical studies suggests that there may be a causal association between prostate cancer and the human papilloma virus (HPV). As HPV is a vaccine-preventable pathogen, the possibility of a role in prostate cancer causation may reinforce the importance of effective HPV vaccination campaigns. This is of particular relevance in light of the COVID-19 pandemic, which may have considerable effects on HPV vaccine uptake and distribution.

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1535. Impact of Defunding Family Planning Health Centers on Gonorrhea and Chlamydia Cases in Iowa: A Spatiotemporal Analysis

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.1715 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S768-S768

Author(s):

Megan L Srinivas ◽

Eileen Yang ◽

Weiming Tang ◽

Joseph Tucker

Keyword(s):

Family Planning ◽

Low Income ◽

Rural Areas ◽

Spatiotemporal Analysis ◽

Incidence Rates ◽

Health Centers ◽

Transmitted Infection ◽

Missed Opportunities ◽

Linear Regression Modeling ◽

The Impact

Abstract Background Fifteen states have defunded family planning health centers (FPHCs), causing thousands to be left without health services. This has accelerated in the COVID-19 era. FPHCs provide low-income individuals in rural areas with essential primary care services, including sexually transmitted infection prevention, testing, and treatment. The purpose of this analysis is to use spatiotemporal methods to examine the impact of FPHC closures in Iowa on the reported number of gonorrhea and chlamydia cases at the county level. Methods This analysis investigates the association between FPHC closures and changes in the number of gonorrhea and chlamydia cases between 2016 and 2018. Iowa implemented defunding policies for family planning clinics, resulting in four FPHC closures in June 2017. 2016 pre-closure STI incidence rates were compared to 2018 post-closure rates. Gonorrhea and chlamydia rates in the four Iowa counties with clinic closures were compared to the 95 Iowa counties without closures. T tests were used to compare changes in reported gonorrhea and chlamydia rates in the two settings. Linear regression modeling was used to determine the relationship between clinic closures and changes in gonorrhea and chlamydia cases. Results The gonorrhea burden in Iowa increased from 83 cases per 100,000 people in 2016 to 153.8 cases per 100,000 people in 2018. The four counties with clinic closures experienced a significantly larger increase (absolute 217 cases per 100,000 population) in their gonorrhea rate compared to counties without FPHC closures (absolute 121 cases per 100,000 population). There was also a significant relationship between clinic closures and increasing gonorrhea rates (p = 0.0015). Over the three-year period, there was no change in chlamydia rates (p = 0.1182). However, there was a trend towards counties with more FPHC closures having a higher number of chlamydia cases (p = 0.057). Conclusion Despite the fact that many STI diagnoses are made and reported by FPHCs, our data suggest that clinic closures may have contributed to an increase in gonorrhea and chlamydia cases. This is consistent with delayed diagnoses and missed opportunities for providing essential STI services to vulnerable and under-served rural residents. Legislative action is urgently needed to curtail this trend. Disclosures All Authors: No reported disclosures

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