Annals of Tropical Medicine and Public Health

: 2017  |  Volume : 10  |  Issue : 1  |  Page : 293--294

Prevalence of opisthorchiasis detected by stool examination: Relationship to Chi River system in Thailand

Beuy Joob1, Viroj Wiwanitkit2,  
1 Sanitation 1 Medical Academic Center, Bangkok, Thailand
2 Hainan Medical University, Haikou, China

Correspondence Address:
Beuy Joob
Sanitation 1 Medical Academic Center, Bangkok, Thailand

How to cite this article:
Joob B, Wiwanitkit V. Prevalence of opisthorchiasis detected by stool examination: Relationship to Chi River system in Thailand.Ann Trop Med Public Health 2017;10:293-294

How to cite this URL:
Joob B, Wiwanitkit V. Prevalence of opisthorchiasis detected by stool examination: Relationship to Chi River system in Thailand. Ann Trop Med Public Health [serial online] 2017 [cited 2020 Jul 9 ];10:293-294
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Full Text

Dear Sir,

Opisthorchiasis of liver fluke infestation is an important tropical parasitic infestation. High prevalence is observed in countries of Indochina and countries near Mekong river.[1] The importance of this parasitic infestation is that long term chronic infestation can result in cholangiocarcinoma, which is a disease with high fatality.[2] To control this disease, the surveillance of infection in human host and intermediate host is an important attempt adding to the distribution of antiparasitic drugs. There are some interesting reports trying to relate the prevalence of the disease in human beings to geographic setting. In two duplicated recent reports by Rujirakul et al., “land use” is defined as an important determinant of the prevalence of human infection by Geographic Information Systems (GIS) study.[3],[4] However, those reports did not mainly focus on the exact geological and geographical parameters. Here, the authors try to find a relationship between the prevalence of opisthorchiasis detected by stool examination in human cases living in Chi River system area in the northeastern region of Thailand, where the highest prevalence of cholangiocarcinoma is documented. The authors find the relationship between the reported prevalence and the geography of the river. The reported prevalence in the recent reports of the last 5 years [3],[4],[5],[6] are used for further assessment. Mapping of the reported prevalence with relationship to geographic setting is shown in [Figure 1]. The relationship between prevalence and distance relating to Chi River system (distance from the origin along the river line and distance from the main river line) is assessed [Table 1]. It can be seen that the more far the setting along the river line of the river the more the prevalence. Also, the area at a more distance away from the main river line has a trend of lower prevalence. This relationship is, hereby, first reported in the global literature. The results can support a previous report on “the existence of a longitudinal gradient in trematode abundance along the river with a decreasing downstream-to-upstream continuum.”[7]{Figure 1}{Table 1}

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