Effect of Climatic Factors and Population Density on the Distribution of Dengue in Sri Lanka: A GIS Based Evaluation for Prediction of Outbreaks

Abstract

Dengue is one of the major hurdles to the public health in Sri Lanka, causing high morbidity and mortality. The present study focuses on the use of geographical information systems (GIS) to map and evaluate the spatial and temporal distribution of dengue in Sri Lanka from 2009 to 2014 and to elucidate the association of climatic factors with dengue incidence. Epidemiological, population and meteorological data were collected from the Epidemiology Unit, Department of Census and Statistics and the Department of Meteorology of Sri Lanka. Data were analyzed using SPSS (Version 20, 2011) and R studio (2012) and the maps were generated using Arc GIS 10.2. The dengue incidence showed a significant positive correlation with rainfall (p<0.0001). No positive correlation was observed between dengue incidence and temperature (p = 0.107) or humidity (p = 0.084). Rainfall prior to 2 and 5 months and a rise in the temperature prior to 9 months positively correlated with dengue incidence as based on the auto-correlation values. A rise in humidity prior to 1 month had a mild positive correlation with dengue incidence. However, a rise in humidity prior to 9 months had a significant negative correlation with dengue incidence based on the auto-correlation values. Remote sensing and GIS technologies give near real time utility of climatic data together with the past dengue incidence for the prediction of dengue outbreaks. In that regard, GIS will be applicable in outbreak predictions including prompt identification of locations with dengue incidence and forecasting future risks and thus direct control measures to minimize major outbreaks.

Spatiotemporal mapping of dengue cases in Sleman district, Indonesia year 2014-2017

“…Population density is well known to have a contribution on dengue transmission, previous research in Sri Lanka found that dengue incidence associated with population density where high dengue incidence has occurred in high population density. 10 In this research, we found a similar result; it seems that the number of dengue incidence has an association with population density. Areas in the urban characteristic such as Depok sub-district then next Mlati, Godean and Gamping are majority have higher cases compared to low population subdistrict which is located in rural or transition rural-urban.…”

Host-vector interaction in dengue: a simple mathematical model

“…An analysis of extensive data on dengue cases reported by the Epidemiology Unit of the Ministry of Health, indicates that the pattern of development of an outbreak follows the trend of the equation (15) to a significant level of confidence [18]. The distribution of dengue cases in Sri Lanka from 2010 to 2017 are plotted in Figure1a.…”

“…However, mosquitoes which bite at night may also act as dengue vectors. Increased human population density, effect of climate on mosquito breeding and presence of several stereotypes of the virus and human reservoirs with marginal to severe clinical manifestations Ceylon Medical Journal 2018; 63: 58-64 DOI: http://doi.org/10.4038/cmj.v63i2.8670 complicate the epidemiology of the disease [18][19][20]. The simple model presented here examines the development of dengue infection in an environment of constant human and mosquito populations.…”

Heat Waves Research and Impacts on Human Health: The Need for Studies in Nigeria: A Review

“…heat cramps, heat syncope, heat exhaustion, heat stroke and possible death [25][26][27]. These studies all identified temperature extremes as a factor that can affect physiological functioning, mood behavior and workplace productivity, especially amongst outdoor workers.…”