Climate variation drives dengue dynamics

Dengue, a viral infection transmitted between people by mosquitoes, is one of the most rapidly spreading diseases in the world. Here, we report the analyses covering 11 y (2005–2015) from the city of Guangzhou in southern China. Using the first 8 y of data to develop an ecologically based model for the dengue system, we reliably predict the following 3 y of dengue dynamics—years with exceptionally extensive dengue outbreaks. We demonstrate that climate conditions, through the effects of rainfall and temperature on mosquito abundance and dengue transmission rate, play key roles in explaining the temporal dynamics of dengue incidence in the human population. Our study thus contributes to a better understanding of dengue dynamics and provides a predictive tool for preventive dengue reduction strategies.

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Key Factors Influencing the Incidence of West Nile Virus in Burleigh County, North Dakota

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15091928 ◽

2018 ◽

Vol 15 (9) ◽

pp. 1928 ◽

Cited By ~ 1

Author(s):

Hiroko Mori ◽

Joshua Wu ◽

Motomu Ibaraki ◽

Franklin Schwartz

Keyword(s):

West Nile Virus ◽

North Dakota ◽

Transmission Rate ◽

Virus Transmission ◽

Correlation Coefficients ◽

West Nile ◽

Mosquito Abundance ◽

River Flooding ◽

Disease Case ◽

The City

The city of Bismarck, North Dakota has one of the highest numbers of West Nile Virus (WNV) cases per population in the U.S. Although the city conducts extensive mosquito surveillance, the mosquito abundance alone may not fully explain the occurrence of WNV. Here, we developed models to predict mosquito abundance and the number of WNV cases, independently, by statistically analyzing the most important climate and virus transmission factors. An analysis with the mosquito model indicated that the mosquito numbers increase during a warm and humid summer or after a severely cold winter. In addition, river flooding decreased the mosquito numbers. The number of WNV cases was best predicted by including the virus transmission rate, the mosquito numbers, and the mosquito feeding pattern. This virus transmission rate is a function of temperature and increases significantly above 20 °C. The correlation coefficients (r) were 0.910 with the mosquito-population model and 0.620 with the disease case model. Our findings confirmed the conclusions of other work on the importance of climatic variables in controlling the mosquito numbers and contributed new insights into disease dynamics, especially in relation to extreme flooding. It also suggested a new prevention strategy of initiating insecticides not only based on mosquito numbers but also 10-day forecasts of unusually hot weather.

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The 2018–2019 weak El Niño: Predicting the risk of a dengue outbreak in Machala, Ecuador

10.5194/egusphere-egu21-14259 ◽

2021 ◽

Author(s):

Desislava Petrova ◽

Xavier Rodó ◽

Rachel Sippy ◽

Joan Ballester ◽

Raul Mejía ◽

...

Keyword(s):

Southern Oscillation ◽

Climatic Conditions ◽

Transmission Model ◽

Local Climate ◽

Climate Conditions ◽

Dengue Outbreak ◽

Dengue Transmission ◽

Forecast Lead Time ◽

Out Of Sample ◽

Dengue Outbreaks

<p>Sea surface temperature conditions in the central-eastern tropical Pacific indicated a mild El Ni&#241;o event in October 2018, which continued throughout the spring of 2019. The global El Ni&#241;o Southern Oscillation (ENSO) forecast consensus was that these generally weak warm patterns would persist at least until the end of the summer. El Ni&#241;o and its impact on local climatic conditions in southern coastal Ecuador influence the inter-annual transmission of dengue fever in the region. In this study, we use an ENSO model to issue forecasts of El Ni&#241;o for the year 2019, which are then used to predict local climate variables, precipitation and minimum temperature, in the city of Machala, Ecuador. All these forecasts are incorporated in a dengue transmission model, specifically developed and tested for this area, to produce out-of-sample predictions of dengue risk. Predictions are issued at the beginning of January 2019 for the whole year, thus providing the longest forecast lead time of 12 months. Preliminary results indicated that the mild El Ni&#241;o event did not provide the optimum climate conditions for dengue transmission, with the model predicting a very low probability of a dengue outbreak during the typical peak season in Machala in 2019. This is contrary to 2016, when a large El Ni&#241;o event resulted in excess rainfall and warmer temperatures in the region, and a dengue outbreak occurred 3 months earlier than expected. This event was successfully predicted using a similar prediction framework to the one applied here. With the present study, we continue our &#160;efforts to build and test a climate service tool to issue early warnings of dengue outbreaks in the region.</p>

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Spatial–temporal dynamics and driving factor analysis of urban ecological land in Zhuhai city, China

Scientific Reports ◽

10.1038/s41598-020-73167-0 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Yunfeng Hu ◽

Yunzhi Zhang

Keyword(s):

Temporal Dynamics ◽

Landscape Heterogeneity ◽

Southern China ◽

Transition Probability ◽

Temporal Analysis ◽

Center Of Gravity ◽

Ecological Value ◽

Landscape Index ◽

Land Protection ◽

The City

Abstract Ecological land is a type of land that has considerable ecological value. Understanding the evolution of urban ecological land in Zhuhai, China, holds great significance for revealing the evolution of ecological land in the Dawan District of southern China. We explored the temporal and spatial variation in urban ecological land in Zhuhai using the transformation matrix, equivalent ecological land, landscape index and ecological land center of gravity migration methods. Multivariate logistic regression was used to analyze the mechanism of ecological land change, and a transition probability map of the ecological land in the study area was drawn. The results showed the following. (1) From 1991 to 2018, the area of ecological land in Zhuhai city continuously decreased, with a reduction in area of 274.8 km2, or 32.3%. Sharp changes mainly occurred from 1991 to 2000. (2) The ecological land in the study area has gradually become fragmented, and the degree of landscape heterogeneity has increased. Affected by the expansion of the outer edge of the city to the southwest and the construction of ecological land within the city, the center of gravity of the ecological land has shifted to the northeast by 1346 m. (3) The elevation, slope, distance from built-up land and growth rate of built-up land are important factors influencing the transformation of ecological land. In the future, rivers and shallow coastal waters, tidal flats, and grasslands in the study area have the highest probability of transformation. The Jinwan District and Xiangzhou District will face severe ecological land protection pressure. The method of spatial–temporal analysis of urban ecological land developed in this paper can be applied in similar studies on other cities, and the results obtained for Zhuhai, China, have reference value for future urban planning and ecological protection work.

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Development of a mechanistic dengue simulation model for Guangzhou

Epidemiology and Infection ◽

10.1017/s095026881900030x ◽

2019 ◽

Vol 147 ◽

Author(s):

G. Mincham ◽

K. L. Baldock ◽

H. Rozilawati ◽

C. R. Williams

Keyword(s):

Simulation Model ◽

Control Strategies ◽

Dengue Infection ◽

Management Strategies ◽

Surveillance Data ◽

Effective Vaccine ◽

Dengue Transmission ◽

Dengue Outbreaks ◽

Computer Based ◽

The City

AbstractDengue infection in China has increased dramatically in recent years. Guangdong province (main city Guangzhou) accounted for more than 94% of all dengue cases in the 2014 outbreak. Currently, there is no existing effective vaccine and most efforts of control are focused on the vector itself. This study aimed to evaluate different dengue management strategies in a region where this disease is emerging. This work was done by establishing a dengue simulation model for Guangzhou to enable the testing of control strategies aimed at vector control and vaccination. For that purpose, the computer-based dengue simulation model (DENSiM) together with the Container-Inhabiting Mosquito Simulation Model (CIMSiM) has been used to create a working dengue simulation model for the city of Guangzhou. In order to achieve the best model fit against historical surveillance data, virus introduction scenarios were run and then matched against the actual dengue surveillance data. The simulation model was able to predict retrospective outbreaks with a sensitivity of 0.18 and a specificity of 0.98. This new parameterisation can now be used to evaluate the potential impact of different control strategies on dengue transmission in Guangzhou. The knowledge generated from this research would provide useful information for authorities regarding the historic patterns of dengue outbreaks, as well as the effectiveness of different disease management strategies.

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EL NINO RELATED CLIMATE AND DENGUE FEVER CASES IN JEDDAH, SAUDI ARABIA

FLORA AND FAUNA ◽

10.33451/florafauna.v25i1pp91-99 ◽

2019 ◽

Vol 25 (1) ◽

Author(s):

MASROOR ALI KHAN ◽

KHALID AL GHAMDI ◽

JAZEM A. MEHYOUB ◽

RAKHSHAN KHAN

Keyword(s):

Relative Humidity ◽

Dengue Fever ◽

El Niño ◽

Significant Relationship ◽

El Nino ◽

Climate Data ◽

Light Traps ◽

Mosquito Abundance ◽

Dengue Transmission ◽

The Relationship

The focus of this study is to find the relationship between El Nino and dengue fever cases in the study area.Mosquito density was recorded with the help of light traps and through aspirators collection. Climate data were obtained from National Meteorology and Environment centre. (Year wise El Nino and La Nina data are according to NOAA & Golden Gate Weather Services). Statistical methods were used to establish the correlation coefficient between different factors. A high significant relationship was observed between Relative Humidity and Dengue fever cases, but Aedes abundance had no significant relationship with either Relative humidity and Temperature. Our conclusion is that the El Nino does not affect the dengue transmission and Aedes mosquito abundance in this region, which is supported by earlier works.

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The importance of changing urban scenery in the assessment of citizens’ soundscape perception. On the need for different time-related points of view

Noise Mapping ◽

10.1515/noise-2021-0011 ◽

2021 ◽

Vol 8 (1) ◽

pp. 138-161

Author(s):

Jerónimo Vida Manzano ◽

José Antonio Almagro Pastor ◽

Rafael García Quesada

Keyword(s):

Urban Areas ◽

Noise Exposure ◽

Noise Control ◽

Action Plan ◽

Heavy Traffic ◽

Legal Protection ◽

Complementary Method ◽

Reduction Strategies ◽

The Right ◽

The City

Abstract The city of Granada is experimenting a big urban transformation, attending national and international commitments on clean air, energy efficiency and savings linked to greenhouse gases reduction strategies and sustainable development action plans. This situation constitutes a good scenario for new noise control approaches that take into account the sound variable and citizens empowering in urban design, such as the soundscape assessment of urban territory. In this way, soundscape tools have been used in Granada as a complementary method for environmental noise characterisation where traditional noise control techniques are difficult to be carried out or give limited results. After 2016 strategic noise map and in the preparation of the new noise action plan, the city came across a great acoustic challenge in a new area located outskirts characterised by growing urbanisation, still under development, the greatest legal protection because of sensitive teaching and hospital buildings and the greatest noise exposure from nearby ring-way supporting heavy traffic flow. As quiet urban areas are not characterised by the absence of noise but for the presence of the right noise, this research intended to provide the local administration with results and proposals to transform this conflict area in a pleasant or quiet urban place. Main results came from important and significative differences in morning and evening characterisation, as great differences appear in soundscape assessment over the day and along the soundwalk path, indicating the importance of time and local issues to adequately characterised citizens perception to be considered by administration in the development of strategies and effective noise control actions.

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The shifting landscape of tick-borne zoonoses: tick-borne encephalitis and Lyme borreliosis in Europe

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2001.0893 ◽

2001 ◽

Vol 356 (1411) ◽

pp. 1045-1056 ◽

Cited By ~ 195

Author(s):

Sarah E. Randolph

Keyword(s):

Lyme Borreliosis ◽

Temporal Dynamics ◽

Transmission Rate ◽

Climate Change Scenarios ◽

Vector Borne Diseases ◽

Tick Borne Encephalitis ◽

Tbe Virus ◽

The Usa ◽

Rate Of Emergence ◽

The Baltic

The two major vector-borne diseases of northern temperate regions, tick-borne encephalitis (TBE) and Lyme borreliosis (LB), show very different epidemiological patterns, but both have increased significantly in incidence since the 1980s. Insight into the temporal dynamics of TBE, gained from statistical analysis of spatial patterns integrated with biological explanation, suggests that the recent increases in TBE cases in Central Europe and the Baltic States may have arisen largely from changes in human behaviour that have brought more people into contact with infected ticks. Under forecast climate change scenarios, it is predicted that enzootic cycles of TBE virus may not survive along the southern edge of their present range, e.g. in Slovenia, Croatia and Hungary, where case numbers are indeed decreasing. New foci, however, are predicted and have been observed in Scandinavia. At the same time, human impact on the landscape, increasing both the habitat and wildlife hosts of ticks, has allowed tick populations to multiply significantly. This probably accounts for a genuine emergence of LB, with its high potential transmission rate, in both the USA and Europe, although the rate of emergence has been exaggerated by improved surveillance and diagnosis.

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ESTIMATION OF LONG-TERM CHANGES IN QUALITATIVE CHARACTERISTICS OF THE OKA RIVER RUNOFF

Prirodoobustrojstvo ◽

10.26897/1997-6011-2021-5-98-104 ◽

2021 ◽

pp. 98-104

Author(s):

G. KH. ISMAIYLOV ◽

◽

N. V. MURASCHENKOVA ◽

I. G. ISMAIYLOVA

Keyword(s):

River Runoff ◽

Maximum Concentration ◽

Temporal Dynamics ◽

Ammonium Nitrogen ◽

Oil Products ◽

Copper Compounds ◽

Long Term Changes ◽

The City ◽

Qualitative Characteristics

The results of the analysis and assessment of long-term changes in the qualitative characteristics of the Oka River runoff are presented. To analyze the temporal dynamics of the variability of the average annual and maximum concentrations of pollutants in the runoff of the Oka River, we used long-term observational data on typical pollutants for the period 1984-2019. The assessment of the state of the quality of surface waters of the Oka River was carried out according to the values of the concentrations of pollutants in the upper, middle and lower reaches of the river. The dynamics of the main pollutants of the following indicators is considered: ammonium nitrogen, oil products, copper and zinc compounds and easily oxidized organic substances. It was found that in the upper reaches of the river (according to observations of the Oka – Orel city) the main pollutants are ammonium nitrogen and copper compounds, the average annual concentrations of which respectively increased to 9 values. A similar situation was observed downstream of the river (the Oka River – Kaluga city). As a result of the analysis, it was revealed that more noticeable changes in the concentration of pollutants are observed in the section of the river from the city of Murom to the city of Dzerzhinsk. Near the city of Murom, the content of oil products in the water sharply increases. From the beginning of the study period (1984) and until 1995, the average annual concentration varied from 5 to 30 values, and the maximum concentration in the year in creased to 87 values. After 2000, the content of oil products in water dropped sharply and the average annual value did not exceed 3 values, and the maximum concentration was 4-6 values. The paper analyzes the frequency of cases of exceeding the maximum permissible concentrations of pollutants in the Oka River in the mouth of the river. There was a high repeatability of the content of copper compounds in water, which varied from 70 to 88%. The frequency of cases of excess of easily oxidized organic matter in the mouth of the Oka River varied from 64 to 74%. Relatively low, although stable, the repeatability of the content of oil products in water remained, which ranged from 23 to 42%.

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Simulation and prediction of dengue outbreaks based on an SIR model with a time-dependent transmission rate including meteorological data. An example for Colombo and Jakarta

International Journal of Biomathematics ◽

10.1142/s179352452150073x ◽

2021 ◽

pp. 2150073

Author(s):

Peter Heidrich ◽

Thomas Götz

Keyword(s):

Transmission Rate ◽

Meteorological Data ◽

Weather Conditions ◽

Time Dependent ◽

Data Sets ◽

Vector Borne Diseases ◽

Dengue Outbreaks ◽

Vector Borne ◽

Text Model ◽

Periodic Transmission

Vector-borne diseases can usually be examined with a vector–host model like the [Formula: see text] model. This, however, depends on parameters that contain detailed information about the mosquito population that we usually do not know. For this reason, in this article, we reduce the [Formula: see text] model to an [Formula: see text] model with a time-dependent and periodic transmission rate [Formula: see text]. Since the living conditions of the mosquitos depend on the local weather conditions, meteorological data sets flow into the model in order to achieve a more realistic behavior. The developed [Formula: see text] model is adapted to existing data sets of hospitalized dengue cases in Jakarta (Indonesia) and Colombo (Sri Lanka) using numerical optimization based on Pontryagin’s maximum principle. A previous data analysis shows that the results of this parameter fit are within a realistic range and thus allow further investigations. Based on this, various simulations are carried out and the prediction quality of the model is examined.

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Rapid Invasion of Spartina Alterniflora in the Coastal Zone of Mainland China: Spatiotemporal Patterns and Human Prevention

Sensors ◽

10.3390/s19102308 ◽

2019 ◽

Vol 19 (10) ◽

pp. 2308 ◽

Cited By ~ 15

Author(s):

Dehua Mao ◽

Mingyue Liu ◽

Zongming Wang ◽

Lin Li ◽

Weidong Man ◽

...

Keyword(s):

Spartina Alterniflora ◽

Temporal Dynamics ◽

Mainland China ◽

Invasive Species Management ◽

Invasion Mechanism ◽

Coastal Cities ◽

Area Increase ◽

Multi Temporal ◽

The City ◽

Invasion Patterns

Given the extensive spread and ecological consequences of exotic Spartina alterniflora (S. alterniflora) over the coast of mainland China, monitoring its spatiotemporal invasion patterns is important for the sake of coastal ecosystem management and ecological security. In this study, Landsat series images from 1990 to 2015 were used to establish multi-temporal datasets for documenting the temporal dynamics of S. alterniflora invasion. Our observations revealed that S. alterniflora had a continuous expansion with the area increasing by 50,204 ha during the considered 25 years. The largest expansion was identified in Jiangsu Province during the period of 1990–2000, and in Zhejiang Province during the periods 2000–2010 and 2010–2015. Three noticeable hotspots for S. alterniflora invasion were Yancheng of Jiangsu, Chongming of Shanghai, and Ningbo of Zhejiang, and each had a net area increase larger than 5000 ha. Moreover, an obvious shrinkage of S. alterniflora was identified in three coastal cities including the city of Cangzhou of Hebei, Dongguan, and Jiangmen of Guangdong. S. alterniflora invaded mostly into mudflats (>93%) and shrank primarily due to aquaculture (55.5%). This study sheds light on the historical spatial patterns in S. alterniflora distribution and thus is helpful for understanding its invasion mechanism and invasive species management.

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