Influence of socio-economic status and environmental factors on serologically diagnosed Japanese encephalitis cases in the state of West Bengal, India during 2005-2010

Arindam Sarkar, Debjani Taraphdar, Bansi B. Mukhopadhyay, Manish Kumar, Subhra K. Mukhopadhyay, Shyamalendu Chatterjee

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DOI: 10.4236/health.2012.41002                

Abstract

Objectives: The main aim of the current study is to examine the influence of socio-economic status and environmental factors on serologically diagnosed Japanese encephalitis cases in the state of West Bengal, India during 2005-2010. Materials and methods: A total of 648 blood/CSF specimens were collected and/or referred from the suspected AES cases, admitted in the different medical colleges and hospitals of the state during the year of 2005-2010. These specimens were subjected to JE Mac ELISA to determine the actual JE case amongst these AES. The association of the socio-economic status and environmental factors with the serologically diagnosed JE positive cases was studied by a statistical analysis through Normal Deviate test or Z test. Result: Out of 648 specimens, only 175 (27.0%) specimens were reactive to JE IgM antibody, of which 60.0% were from the male individuals and 40.0% from the female population. Major cases were observed in the age group of 0 - 10 years; followed by 11 - 20 years. Regarding literacy, only 58.3% cases had no education and 41.7% were from the literate with varying level of education, i.e., from primary level to post gra- duate level. A total of 65.7% cases were from low income group where as only 34.3% cases were from high income group. Regarding house type, 62.3% cases lived in mud house and 37.7% cases lived in the brick house. In most of the cases (74.3%), persons were living in close proximity to rice fields/lakes/ponds. 69.7% cases were found to occur in the monsoon and post-monsoon period whereas 30.3% cases were reported in the pre-monsoon period. Conclusion: Our study concludes that socio-economic status and environmental conditions were statistically significant contextual risk factors for serologically diagnosed JE incidences in West Bengal where JE is proved to be endemic in nature and such study constitutes a new report of this kind in the region.

Keywords

Japanese Encephalitis; Socio-Economic Status; Acute Encephalitis Syndrome (AES); West Bengal

Conflicts of Interest

The authors declare no conflicts of interest.

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