S Thammapalo

Publications (2)5.69 Total impact

• Source

  Available from: Apiwat Tawatsin

  Article: Geographical gradient of mean age of dengue haemorrhagic fever patients in northern Thailand.

  Y Nagao, A Tawatsin, S Thammapalo, U Thavara
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  ABSTRACT: Dengue haemorrhagic fever (DHF) is caused by dengue virus transmitted by Aedes mosquitoes; mean age of patients varies temporally and geographically. Variability in age of patients may be due to differences in transmission intensity or demographic structure. To compare these two hypotheses, the mean age of DHF patients from 90 districts in northern Thailand (1994-1996, 2002-2004) was regressed against (i) Aedes abundance or (ii) demographic variables (birthrate, average age) of the district. We also developed software to quantify direction and strength of geographical gradients of these variables. We found that, after adjusting for socioeconomics, climate, spatial autocorrelation, the mean age of patients was correlated only with Aedes abundance. The geographical gradient of mean age of patients originated from entomological, climate, and socioeconomic gradients. Vector abundance was a stronger determinant of mean age of patients than demographic variables, in northern Thailand.
  Epidemiology and Infection 05/2011; 140(3):479-90. · 2.84 Impact Factor
• Article: Environmental factors and incidence of dengue fever and dengue haemorrhagic fever in an urban area, Southern Thailand.

  S Thammapalo, V Chongsuvivatwong, A Geater, M Dueravee
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  ABSTRACT: Using the enumeration district (ED) block level this study looked at the incidence of dengue fever and dengue haemorrhagic fever (DF/DHF) within the Songkhla municipality in Thailand. Each of the 146 blocks in this area were considered as study units and surveyed for their environmental characteristics. A total of 287 cases of DH/DHF occurring in the year 1998 were selected for this study and the location of their homes mapped. Clustering analysis showed point clustering of the homes (P<0.0001) which was probably due to high density habitation, without any actual prevalence of case clustering. There was no evidence of clustering of the ED blocks with an incidence of DF/DHF (P=0.32). DF/DHF incidence for each block was strongly associated with the percentages of shop-houses, brick-made houses and houses with poor garbage disposal (all P<0.01). DF/DHF control should be emphasized for the areas which have a predominance of these housing types.
  Epidemiology and Infection 01/2008; 136(1):135-43. · 2.84 Impact Factor