The Use of Remote Sensing For Estimating the Impact of Climate Change on Japanese Encephalitis Disease Distribution

要旨

In Thailand, Japanese encephalitis (JE) occurs primarily in the north and northeast regions and remains a public health problem because the case fatality rate is 10-50%. The disease has recently been recognized in new areas and has recurred in previously endemic areas. The environmental interactions are important in the various effects of temperature and rainfall. To tackle with problems on JE, the development of a model that can predict JE case as a function of these environmental factors is needed. Two models have been developed in this study based on time-series analysis. One is in Chiangrai Province that shows high JE cases in Thailand and the other is for the whole country, Thailand. The accuracy (R2) of these models are 0.970 and 0.783 respectively in 1992-1993 in which model parameters have been determined. The models were applied to 1998 data for validation, which showed the accuracy (R2) of 0.727 and 0.621 respectively. Remote sensing data from NOAA AVHRR is introduced to identify rice fields to make it possible to predict JE cases at near real time at the seasonal time scale in Thailand. The accuracy (R2) of this model is 0.608 in 1998 between the JE case from a model and the actual.