Spatiotemporal spread of chikungunya virus in Sarawak, Malaysia

2021 ◽  
Author(s):  
Sarat Dass ◽  
Romano Ngui ◽  
Balvinder Singh Gill ◽  
Yoke Fun Chan ◽  
Wan Yusoff Wan Sulaiman ◽  
...  
Keyword(s):  
Spatial Data ◽  
Rural Areas ◽  
Urban Areas ◽  
Chikungunya Virus ◽  
Reproduction Number ◽  
Control Measures ◽  
River Networks ◽  
Scan Statistic ◽  
R Software ◽  
Time Scan

Abstract Background We studied the spatiotemporal spread of a chikungunya virus (CHIKV) outbreak in Sarawak state, Malaysia, during 2009–2010. Methods The residential addresses of 3054 notified CHIKV cases in 2009–2010 were georeferenced onto a base map of Sarawak with spatial data of rivers and roads using R software. The spatiotemporal spread was determined and clusters were detected using the space-time scan statistic with SaTScan. Results Overall CHIKV incidence was 127 per 100 000 population (range, 0–1125 within districts). The average speed of spread was 70.1 km/wk, with a peak of 228 cases/wk and the basic reproduction number (R0) was 3.1. The highest age-specific incidence rate was 228 per 100 000 in adults aged 50–54 y. Significantly more cases (79.4%) lived in rural areas compared with the general population (46.2%, p<0.0001). Five CHIKV clusters were detected. Likely spread was mostly by road, but a fifth of rural cases were spread by river travel. Conclusions CHIKV initially spread quickly in rural areas mainly via roads, with lesser involvement of urban areas. Delayed spread occurred via river networks to more isolated areas in the rural interior. Understanding the patterns and timings of arboviral outbreak spread may allow targeted vector control measures at key transport hubs or in large transport vehicles.

scholarly journals Estimation of Building Heights and DEM Accuracy Assessment Using ICESat-2 Data Products

2021 ◽  
Vol 10 (1) ◽  
pp. 37
Author(s):  
Goddu Pavan Sai Goud ◽  
Ashutosh Bhardwaj
Keyword(s):  
Spatial Data ◽  
Rural Areas ◽  
Urban Areas ◽  
Accuracy Assessment ◽  
Urban Expansion ◽  
Population Expansion ◽  
Cost Effective ◽  
Absolute Error ◽  
Google Earth ◽  
Surface Geometry

The use of remote sensing for urban monitoring is a very reliable and cost-effective method for studying urban expansion in horizontal and vertical dimensions. The advantage of multi-temporal spatial data and high data accuracy is useful in mapping urban vertical aspects like the compactness of urban areas, population expansion, and urban surface geometry. This study makes use of the ‘Ice, cloud, and land elevation satellite-2′ (ICESat-2) ATL 03 photon data for building height estimation using a sample of 30 buildings in three experimental sites. A comparison of computed heights with the heights of the respective buildings from google image and google earth pro was done to assess the accuracy and the result of 2.04 m RMSE was obtained. Another popularly used method by planners and policymakers to map the vertical dimension of urban terrain is the Digital Elevation Model (DEM). An assessment of the openly available DEM products—TanDEM-X and Cartosat-1 has been done over Urban and Rural areas. TanDEM-X is a German earth observation satellite that uses InSAR (Synthetic Aperture Radar Interferometry) technique to acquire DEM while Cartosat-1 is an optical stereo acquisition satellite launched by the Indian Space Research Organization (ISRO) that uses photogrammetric techniques for DEM acquisition. Both the DEMs have been compared with ICESat-2 (ATL-08) Elevation data as the reference and the accuracy has been evaluated using Mean error (ME), Mean absolute error (MAE) and Root mean square error (RMSE). In the case of Greater Hyderabad Municipal Corporation (GHMC), RMSE values 5.29 m and 7.48 m were noted for TanDEM-X 90 and CartoDEM V3 R1 respectively. While the second site of Bellampalli Mandal rural area observed 5.15 and 5.48 RMSE values for the same respectively. Therefore, it was concluded that TanDEM-X has better accuracy as compared to the CartoDEM V3 R1.

scholarly journals Spatial Paradigms in Road Networks and Their Delimitation of Urban Boundaries Based on KDE

2020 ◽  
Vol 9 (4) ◽  
pp. 204 ◽  
Author(s):  
Yuying Lin ◽  
Xisheng Hu ◽  
Mingshui Lin ◽  
Rongzu Qiu ◽  
Jinguo Lin ◽  
...  
Keyword(s):  
Spatial Data ◽  
Rural Areas ◽  
Urban Areas ◽  
Critical Role ◽  
Road Networks ◽  
Spatial Data Analysis ◽  
Easy Method ◽  
Study Region ◽  
Entire Study ◽  
Depth Analysis

An in-depth analysis of urban road network distribution plays a critical role in understanding the urbanization process. However, effective ways to quantitatively analyze the spatial paradigms of road networks are still lacking, and few studies have utilized road networks to rapidly identify urban areas of a region. Thus, using a fast-developing region in the south-eastern costal region of China, Fuzhou City, as a case, we introduced kernel density estimation (KDE) to characterize road networks and quantified the area’s spatial heterogeneity using exploratory spatial data analysis (ESDA) and semivariance analysis (SA). The results show that there is an uneven spatial distribution of the networks both at the regional and downtown levels. At the regional level, there is a conspicuous polarization in the road distribution, with the KDE being much higher in the urban areas than in the rural areas; at the downtown level, the KDE gradually decreases from the center to the periphery. Quantitatively, the ranges of the spatial dependence of the networks are approximately 25 km for the entire study region and 12 km for the downtown area. Additionally, the spatial variations vary among different directions, with greater variations in the northeast–southwest and the southeast–northwest directions compared with the other directions, which is in line with the urban sprawl policy of the study area. Both the qualitative and quantitative results show that the distribution of road networks has a clear urban–rural dual structure, which indicates that road networks can be an active tool in identifying the urban areas of a region. To this end, we propose a quick and easy method to delimit urban areas using KDE. The extraction results of KDE are better than those of the index-based built-up index (IBI), indicating the effectivity and feasibility of our proposed method to identify the urban areas in the region. This research sheds new light on urbanization development research.

scholarly journals Socioeconomic Determinants of Malaria in Selected Urban and Rural Areas in Anambra State, Nigeria

2020 ◽  
pp. 53-64
Author(s):  
C. C. Nduka ◽  
H. N. Chineke ◽  
P. O. Adogu ◽  
A. F. Chizoba
Keyword(s):  
Socioeconomic Factors ◽  
Rural Areas ◽  
Urban Areas ◽  
Control Measures ◽  
Health Concern ◽  
Skilled Workers ◽  
Quality Health Care ◽  
Cross Sectional ◽  
Rural And Urban Areas ◽  
Rural And Urban

Malaria, a disease of poverty, is of significant public health concern. It is endemic in Nigeria with the risk of transmission appearing to be high because of favorable climatic and environmental factors. Increased susceptibility to malaria has also been linked to dirty surroundings that favor the breeding and propagation of the vector, poor access to quality health care and ignorance especially of malaria prevention strategies. However, this study investigated the role of socioeconomic factors responsible for the observed difference in malaria prevalence between selected rural and urban areas of Anambra, Nigeria. A descriptive comparative cross-sectional study, data on demographic and socioeconomic variables were collected from 202 urban and rural respondents, then analyzed using SPSS platform to generate chi-square test of significance. The results were presented in figures, table and charts for clarity. All the subjects were aware of the term malaria but only 63.4% had adequate specific knowledge of malaria. Generally, 25.7% of rural participants had no formal education while the urban group had only 4% of that particular category. About 52.5% of rural participants earned below 50,000 naira monthly, with 14.9% earning above 100,000 naira while the reverse was the case in the urban area. Also, the number of malaria episodes was inversely proportional to the household monthly income (X2=24.30, p<0.001). More episodes of malaria were also reported among the unskilled workers and skilled workers (71.3%) compared to Professionals (28.7%), yet all the participants reported the presence of a healthcare facility <3km from their houses with 95% and 80.2% of them in the rural and urban areas respectively having to pay out-of-pocket for healthcare services. It is clear that socioeconomic factors play a role in the persistence of malaria as an endemic disease in Nigeria. Therefore, existing control measures should incorporate strategies to end poverty and ignorance especially among the rural populace.

scholarly journals Virome in adult Aedes albopictus captured during different seasons in Guangzhou City, China

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Wenqiao He ◽  
Yanxia Chen ◽  
Xiru Zhang ◽  
Mingji Peng ◽  
Da Xu ◽  
...  
Keyword(s):  
Aedes Albopictus ◽  
Rural Areas ◽  
Disease Transmission ◽  
Urban Areas ◽  
Control Measures ◽  
Health System Strengthening ◽  
Female Mosquito ◽  
Hbv Genotype ◽  
Guangzhou City ◽  
Different Seasons

Abstract Background The mosquito Aedes albopictus is an important vector for many pathogens. Understanding the virome in Ae. albopictus is critical for assessing the risk of disease transmission, implementation of vector control measures, and health system strengthening. Methods In this study, viral metagenomic and PCR methods were used to reveal the virome in adult Ae. albopictus captured in different areas and during different seasons in Guangzhou, China. Results The viral composition of adult Ae. albopictus varied mainly between seasons. Over 50 viral families were found, which were specific to vertebrates, invertebrates, plants, fungi, bacteria, and protozoa. In rural areas, Siphoviridae (6.5%) was the most common viral family harbored by mosquitoes captured during winter and spring, while Luteoviridae (1.1%) was the most common viral family harbored by mosquitoes captured during summer and autumn. Myoviridae (7.0% and 1.3%) was the most common viral family in mosquitoes captured in urban areas during all seasons. Hepatitis B virus (HBV) was detected by PCR in a female mosquito pool. The first near full-length HBV genome from Ae. albopictus was amplified, which showed a high level of similarity with human HBV genotype B sequences. Human parechovirus (HPeV) was detected in male and female mosquito pools, and the sequences were clustered with HPeV 1 and 3 sequences. Conclusions Large numbers of viral species were found in adult Ae. albopictus, including viruses from vertebrates, insects, and plants. The viral composition in Ae. albopictus mainly varied between seasons. Herein, we are the first to report the detection of HPeV and HBV in mosquitoes. This study not only provides valuable information for the control and prevention of mosquito-borne diseases, but it also demonstrates the feasibility of xenosurveillance. Graphical Abstract

scholarly journals Epidemiological study of scarlet fever in Shenyang, China

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Huijie Chen ◽  
Ye Chen ◽  
Baijun Sun ◽  
Lihai Wen ◽  
Xiangdong An
Keyword(s):  
Rural Areas ◽  
Scarlet Fever ◽  
Urban Areas ◽  
Primary Schools ◽  
Prevention And Control ◽  
Hot Spot ◽  
Temporal Distribution ◽  
Control Measures ◽  
And Control ◽  
Epidemiological Characteristics

Abstract Background Since 2011, there has been an increase in the incidence of scarlet fever across China. The main objective of this study was to depict the spatiotemporal epidemiological characteristics of the incidence of scarlet fever in Shenyang, China, in 2018 so as to provide the scientific basis for effective strategies of scarlet control and prevention. Methods Excel 2010 was used to demonstrate the temporal distribution at the month level and ArcGIS10.3 was used to demonstrate the spatial distribution at the district/county level. Moran’s autocorrelation coefficient was used to examine the spatial autocorrelation and the Getis-Ord statistic was used to determine the hot-spot areas of scarlet fever. Results A total of 2314 scarlet fever cases were reported in Shenyang in 2018 with an annual incidence of 31.24 per 100,000. The incidence among males was higher than that among females(p<0.001). A vast majority of the cases (96.89%) were among children aged 3 to 11 years. The highest incidence was 625.34/100,000 in children aged 5–9 years. In 2018 there were two seasonal peaks of scarlet fever in June (summer-peak) and December (winter-peak). The incidence of scarlet fever in urban areas was significantly higher than that in rural areas(p<0.001). The incidence of scarlet fever was randomly distributed in Shenyang. There are hotspot areas located in seven districts. Conclusions Urban areas are the hot spots of scarlet fever and joint prevention and control measures between districts should be applied. Children aged 3–11 are the main source of scarlet fever and therefore the introduction of prevention and control into kindergarten and primary schools may be key to the control of scarlet fever epidemics.

Trends and Distribution in Mortality Rates of Coronary Heart Disease in Hexi Corridor of Gansu in China from 2006 to 2015

2019 ◽  
Author(s):  
xinghui li ◽  
xiaolan ren ◽  
yan qiao ◽  
ping xie ◽  
nan wang ◽  
...  
Keyword(s):  
Coronary Heart Disease ◽  
Heart Disease ◽  
Mortality Rate ◽  
Rural Areas ◽  
Urban Areas ◽  
Hexi Corridor ◽  
Gansu Province ◽  
Control Measures ◽  
Urban Rural ◽  
Small Change

Abstract Background: The mortality rate of coronary heart disease (CHD) in China is different from region to region, and there are sex, age and urban-rural differences. This study described trend and distribution of CHD in Hexi corridor of Gansu province from 2006 to 2015. Method: The death data of CHD were obtained using the Death Reporting System of Gansu CDC for 2006-2015. The trend of the death cases of CHD by year, month and its distribution by sex, age and region were studied, and the changing characteristics of epidemiology was analyzed. Results: Overall, The mortality rate of CHD in Hexi corridor showed a decline trend from 2006 to 2015, a tendency that higher in winter and spring, and lowest in summer. The relative mortality of males was higher than that of females ( P < 0.05), increased with age ( P < 0.05), and that of rural areas was higher than that of urban areas ( P < 0.05). The trend analysis of death rate for ten-year showed a marked decline in females, an increase in 18-39 years old, a small change in 40-59 years old, a decrease in over 60 years old, and a downward tendency of urban areas. Further analysis showed that the mortality rate of males were higher than that of females in 18-39 years old and 40-59 years old group and also in urban areas group ( P < 0.05), while no sex difference in over 60 years old group and rural areas group ( P > 0.05). Conclusion: The mortality of CHD in Hexi corridor of Gansu province in China was lower than the national average from 2006 to 2015, but increased gradually in specified population such as in males, young and middle-age, rural areas groups. The prevention and control measures should be strengthened in these special populations.

scholarly journals Epidemiological study of scarlet fever in Shenyang , China

2019 ◽  
Author(s):  
Huijie Chen ◽  
Ye Chen ◽  
Baijun Sun ◽  
Lihai Wen ◽  
Xiangdong An
Keyword(s):  
Rural Areas ◽  
Scarlet Fever ◽  
Urban Areas ◽  
Primary Schools ◽  
Prevention And Control ◽  
Hot Spot ◽  
Temporal Distribution ◽  
Control Measures ◽  
And Control ◽  
Epidemiological Characteristics

Abstract Background: Since 2011, there has been an increase in the incidence of scarlet fever across China. The main objective of this study was to depict the spatiotemporal epidemiological characteristics of the incidence of scarlet fever in Shenyang, China, in 2018 so as to provide the scientific basis for effective strategies of scarlet control and prevention. Methods: Excel 2010 was used to demonstrate the temporal distribution at the month level and ArcGIS10.3 was used to demonstrate the spatial distribution at the district/county level. Moran’s autocorrelation coefficient was used to examine the spatial autocorrelation and the Getis-Ord statistic was used to determine the hot-spot areas of scarlet fever. Results: A total of 2,314 scarlet fever cases were reported in Shenyang in 2018 with an annual incidence of 31.24 per 100,000. The incidence among males was higher than that among females（p＜0.001). A vast majority of the cases (96.89%) were among children aged 3 to 11 years. The highest incidence was 625.34/100,000 in children aged 5-9 years. In 2018 there were two seasonal peaks of scarlet fever in June (summer-peak) and December (winter-peak).The incidence of scarlet fever in urban areas was significantly higher than that in rural areas(p＜0.001).The incidence of scarlet fever was randomly distributed in Shenyang. There are hotspot areas located in seven districts. Conclusions: Urban areas are the hot spots of scarlet fever and joint prevention and control measures between districts should be applied. Children aged 3-11 are the main source of scarlet fever and therefore the introduction of prevention and control into kindergarten and primary schools may be key to the control of scarlet fever epidemics.

scholarly journals Dynamical analysis, optimal control and spatial pattern in an influenza model with adaptive immunity in two stratified population

2022 ◽  
Vol 7 (4) ◽  
pp. 4898-4935
Author(s):  
Mamta Barik ◽  
◽  
Chetan Swarup ◽  
Teekam Singh ◽  
Sonali Habbi ◽  
...  
Keyword(s):  
Optimal Control ◽  
Adaptive Immunity ◽  
Rural Areas ◽  
Urban Areas ◽  
Local Stability ◽  
Reproduction Number ◽  
Equilibrium Points ◽  
Turing Instability ◽  
Dynamical Analysis ◽  
Global Public Health

<abstract><p>Consistently, influenza has become a major cause of illness and mortality worldwide and it has posed a serious threat to global public health particularly among the immuno-compromised people all around the world. The development of medication to control influenza has become a major challenge now. This work proposes and analyzes a structured model based on two geographical areas, in order to study the spread of influenza. The overall underlying population is separated into two sub populations: urban and rural. This geographical distinction is required as the immunity levels are significantly higher in rural areas as compared to urban areas. Hence, this paper is a novel attempt to proposes a linear and non-linear mathematical model with adaptive immunity and compare the host immune response to disease. For both the models, disease-free equilibrium points are obtained which are locally as well as globally stable if the reproduction number is less than 1 (<italic>R</italic><sub>01</sub> &lt; 1 &amp; <italic>R</italic><sub>02</sub> &lt; 1) and the endemic point is stable if the reproduction number is greater then 1 (<italic>R</italic><sub>01</sub> &gt; 1 &amp; <italic>R</italic><sub>02</sub> &gt; 1). Next, we have incorporated two treatments in the model that constitute the effectiveness of antidots and vaccination in restraining viral creation and slow down the production of new infections and analyzed an optimal control problem. Further, we have also proposed a spatial model involving diffusion and obtained the local stability for both the models. By the use of local stability, we have derived the Turing instability condition. Finally, all the theoretical results are verified with numerical simulation using MATLAB.</p></abstract>

scholarly journals Epidemiological study of scarlet fever in Shenyang City, China

2019 ◽  
Author(s):  
Huijie Chen ◽  
Ye Chen ◽  
Baijun Sun ◽  
Lihai Wen ◽  
Xiangdong An
Keyword(s):  
Rural Areas ◽  
Hot Spots ◽  
Scarlet Fever ◽  
Urban Areas ◽  
Primary Schools ◽  
Prevention And Control ◽  
Hot Spot ◽  
Control Measures ◽  
And Control ◽  
Epidemiological Characteristics

Abstract Objectives: To depict the Spatiotemporal epidemiological characteristics of the incidence of scarlet fever in Shenyang, China, in 2018 so as to provide the scientific basis for effective strategies of scarlet control and prevention. Methods: Excel 2010 was used to demonstrate the temporal distribution at the month level and ArcGIS10.3 was used to demonstrate the spatial distribution at the district/county level. Moran’s autocorrelation coefficient was used to examine the spatial autocorrelation and the Getis-Ord statistic was used to determine the hot-spot areas of scarlet fever. Results: A total of 2,314 scarlet fever cases were reported in Shenyang in 2018 with an annual incidence of 31.24 per 100,000. The incidence among males was higher than that among females(X2=95.013, P≤0.001). A vast majority of the cases (96.89%) were among children aged 3 to 11 years. The highest incidence was 625.34/100,000 in children aged 5-9 years. There are two seasonal peaks occurred in June (Summer-peak) and in December (Winter-peak) in 2018. The incidence of scarlet fever in urban areas was significantly higher than that in rural areas(X2=514.115, P≤0.001).The incidence of scarlet fever was randomly distributed in Shenyang. There are hot-spots areas located in seven districts. Conclusions: Urban areas are the hot spots of scarlet fever and joint prevention and control measures between districts should be applied. Children in the kindergartens and the primary school students are the main population of scarlet fever and the time distribution of scarlet fever is highly consistent with their school and vacation time. It is suggested that measure for prevention and control of scarlet fever in kindergartens and primary schools is the key to control the epidemic of scarlet fever.

scholarly journals Epidemiological study of scarlet fever in Shenyang , China

2019 ◽  
Author(s):  
Huijie Chen ◽  
Ye Chen ◽  
Baijun Sun ◽  
Lihai Wen ◽  
Xiangdong An
Keyword(s):  
Rural Areas ◽  
Scarlet Fever ◽  
Urban Areas ◽  
Primary Schools ◽  
Prevention And Control ◽  
Hot Spot ◽  
Temporal Distribution ◽  
Control Measures ◽  
And Control ◽  
Epidemiological Characteristics

Abstract Background : Since 2011, the rising incidence of scarlet fever has exerted a marked influence on people. The main objective of this study was to depict the Spatiotemporal epidemiological characteristics of the incidence of scarlet fever in Shenyang, China, in 2018 so as to provide the scientific basis for effective strategies of scarlet control and prevention. Methods: Excel 2010 was used to demonstrate the temporal distribution at the month level and ArcGIS10.3 was used to demonstrate the spatial distribution at the district/county level. Moran’s autocorrelation coefficient was used to examine the spatial autocorrelation and the Getis-Ord statistic was used to determine the hot-spot areas of scarlet fever. Results: A total of 2,314 scarlet fever cases were reported in Shenyang in 2018 with an annual incidence of 31.24 per 100,000. The incidence among males was higher than that among females（ p ＜0.001). A vast majority of the cases (96.89%) were among children aged 3 to 11 years. The highest incidence was 625.34/100,000 in children aged 5-9 years. There are two seasonal peaks occurred in June (Summer-peak) and in December (Winter-peak) in 2018. The incidence of scarlet fever in urban areas was significantly higher than that in rural areas( p ＜0.001).The incidence of scarlet fever was randomly distributed in Shenyang. There are hotspot areas located in seven districts. Conclusions: Urban areas are the hot spots of scarlet fever and joint prevention and control measures between districts should be applied. Children in the kindergartens and the primary schools are the main population of scarlet fever and measures for prevention and control in kindergartens and primary schools may be the key to control the epidemic of scarlet fever.

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