2 Materials and Methods

2.1 Study Area

Our aim is to predict the dengue outbreak in each of its several districts shown in Figure 2.1.

The map of Bangkok with enumerated 50 districts (Image Source: [@wikiBKK])

Figure 2.1: The map of Bangkok with enumerated 50 districts (Image Source: (Wikipedia 2016)) 

## Warning: package 'tseries' was built under R version 3.3.2

Now, let’s look at some of the descriptive statistics of dengue in Bangkok from year 2008 to 2015. We have the data available for each month throughout the year, however in a few cases data from some of the districts is missing. I will report about the missing data when it is required for our analysis. We have the data about following variables.

  1. Monthly Dengue Incidence (MD) (for each district)
    • Dengue Fever (DF) data.
    • Dengue Haemorrhagic Fever (DHF) and
    • Dengue Shock Syndrome (DSS)
  2. Meteorological Variables (uniform for all districts in Bangkok)
    • Monthly Average Rainfall (MR)
    • Monthly Diurnal Temperature Range (DTR)
  3. Socio-Economic Data (for each district)
    • Population Demographics in different age groups (2014)
    • Number of communities (schools, hospitals, meetup centers etc.) in 2011.
    • Yearly Garbage Collection (2012 to 2014).
  4. Location Specific Data (for each district)
    • Attached to the river stream.
    • Distance from the river stream.

2.2 Meteorological Data

2.2.1 Temperature

The temperatur data is collected as Diurnal Temperature Range abbreviated as DTR. DTR is the difference between the daily maximum and minimum temperature. It is shown in Table 2.1.

Table 2.1: Monthly DTR within the city from 2008 to 2015.
Month 2015 2014 2013 2012 2011 2010 2009 2008
Jan 9.6 11.2 10.3 9.2 9.9 8.6 10.6 9.0
Feb 9.0 8.6 9.0 8.3 8.8 7.2 9.7 7.8
Mar 8.0 8.1 9.1 8.3 7.4 8.9 8.9 8.0
Apr 8.7 8.7 9.2 8.5 8.1 8.4 9.5 8.1
May 8.3 9.3 8.9 8.8 7.6 8.5 8.1 7.0
Jun 8.6 7.6 7.8 7.6 6.7 8.7 7.1 6.9
Jul 7.8 7.4 7.2 6.9 7.7 8.2 7.3 6.4
Aug 7.9 7.9 8.1 7.9 7.4 8.1 8.4 6.4
Sep 8.1 8.1 7.3 7.3 7.4 8.3 8.5 6.7
Oct 7.2 7.9 7.9 7.6 7.7 7.2 8.6 6.9
Nov 8.0 8.5 8.5 8.0 8.6 7.6 9.3 7.0
Dec 8.4 8.6 10.5 9.7 9.2 8.7 9.3 9.0

The visualization of DTR within Bangkok throughout the years is shown in Fig 2.2 and Fig 2.3.

DTR within Bangkok throughout the years put together shown individually.

Figure 2.2: DTR within Bangkok throughout the years put together shown individually.

DTR within Bangkok throughout the years put together.

Figure 2.3: DTR within Bangkok throughout the years put together.

2.2.2 Rainfall

The data for average monthly rainfall in Bangkok is shown in Table 2.2.

Plotting average monthly rainfall for all the years on the same plot.

Table 2.2: Monthly Rainfall within the city from 2008 to 2015.
Month 2015 2014 2013 2012 2011 2010 2009 2008
Jan 3.5 0.000 32.206 43.354 0.630 99.9 0.0 62.1
Feb 16.8 2.512 4.098 18.654 37.342 2.9 0.0 69.3
Mar 183.9 19.314 35.918 31.888 136.716 14.6 30.2 3.6
Apr 128.9 25.358 64.366 51.914 136.662 17.3 359.6 180.8
May 82.5 125.410 111.540 108.984 246.128 279.3 463.4 257.9
Jun 495.0 125.936 206.946 123.418 196.584 198.8 219.3 163.6
Jul 220.8 122.270 142.212 176.626 288.680 348.7 175.7 221.8
Aug 50.5 218.006 228.214 190.436 292.804 343.1 354.0 172.1
Sep 352.4 203.436 312.220 548.736 266.538 409.5 351.8 335.2
Oct 334.2 206.998 314.090 236.996 337.502 256.3 264.2 399.3
Nov 34.9 51.506 69.286 106.022 1.880 30.6 46.5 36.7
Dec 42.7 25.926 2.060 12.256 0.584 22.7 7.3 0.0
DTR within Bangkok throughout the years put together.

Figure 2.4: DTR within Bangkok throughout the years put together.

2.3 Dengue Incidences

In this study, we only use the data for DHF.

The DHF incidence peaked in 2013 and 2015. It seems that dengue outbreak increases every alternative year.

Figure 2.5: The DHF incidence peaked in 2013 and 2015. It seems that dengue outbreak increases every alternative year.

We can observe a trend in Fig 2.5 that dengue outbreak increases every alternative year. But is it really a pattern? Well, we don’t have enough data for say that, however we will check and see if we can exploit this ‘pattern’ for better prediction of dengue.

The DHF incidence peaked in October and November . It seems that dengue outbreak increases every alternative year.

Figure 2.6: The DHF incidence peaked in October and November . It seems that dengue outbreak increases every alternative year.

The DHF incidence peak every year in the months of October and November. However in the year 2013 it seems that DHF occured for many months continously at an alarming rate.

Figure 2.7: The DHF incidence peak every year in the months of October and November. However in the year 2013 it seems that DHF occured for many months continously at an alarming rate.

2.4 Interaction of Meteorological Variables

The temperature and rainfall data rogether acroos several years

Figure 2.8: The temperature and rainfall data rogether acroos several years

The temperature and rainfall data rogether in the same plot.

Figure 2.9: The temperature and rainfall data rogether in the same plot.

There are 18 districts that are close to stream as shown in Figure 2.1. Their names are:

 [1] "Bang Su"         "Dusit"           "Bang Plad"      
 [4] "Phra Nakhon"     "Bangkok Noi"     "Bangkok Yai"    
 [7] "Thon Buri"       "Khlong San"      "Pom Pram Sattru"
[10] "Samphantawong"   "Bang Rak"        "Sathorn"        
[13] "Bang Kho Laem"   "Yannawa"         "Rat Burana"     
[16] "Khlong Toey"     "Prakanong"       "Bang Na"

References

Wikipedia. 2016. “List of Districts of Bangkok — Wikipedia, the Free Encyclopedia.” https://en.wikipedia.org/w/index.php?title=List_of_districts_of_Bangkok&oldid=732094425.