The correlation of climate factors on dengue transmission in urban area: Bangkok and Singapore cases

Abstract

The objective of this study is to find the correlation between climate factors and dengue incidence rate in Bangkok and Singapore during 2009-2015. Spearman's rank correlation tests with time-lag are performed to investigate the overall correlation between dengue incidence rates and climate factors , minimum, mean, and maximum temperatures, DTR, and rainfall. A Linear and Poisson regression analysis was performed. Spearman's rank correlation tests show that in Bangkok monthly rainfall (r=0.451, p<0.001), the number of rainy days (r=0.411, p<0.001) are positive correlation with 2 month lag time. DTR (r=-0.335, p<0.001) is negative correlation with 2 month lag time. Maximum (r=0.256, p<0.001), mean (r=0.304, p<0.001) and minimum (r=0.323, p<0.001) temperature are positive correlation with 4 month lag time. In Singapore, only minimum temperature (r=-0.299, p<0.001) with 1 month lag time is negative correlation and DTR (r=-0.289, p<0.001) with zero month lag time is positive correlation. The rest has no statically significance (p>0.05). This study concluded, climate factors play moderate role in dengue incidence in Bangkok. There is no statistical significance between rainfall and dengue incidence rate and temperature play a marginal role in Singapore.

Assessing the Effect of Climate Variables on the Incidence of Dengue Cases in the Metropolitan Region of Panama City

“…This conclusions are not surpising as Dengue is a complex problem with many exogenous variables that are not controlled in models . For instance, some authors suggest that it can be attributed to the possibility of having almost constant temperatures throughout the year [47]. Also, there are other factors that can influence the dengue cases, such as: the distribution of objects unintentionally dispersed by man that can serve as a breeding ground once the water can recharge in them, collection of water in containers for human consumption due the limited access to drinking water, which is truly relevant in the case of the metropolitan area of Panama City [48] .…”