Sero-epidemiology of dengue virus infection in Western Terai Region of Nepal

Thesis Report.

ABSTRACT: Dengue fever (DF) is an emerging mosquito borne disease and important public health problem in low land of Terai region. There are limited information on the prevalence of the disease until now. This study was designed to estimate sero-prevalence of dengue virus infection in the post monsoon period (Aug-Nov) of 2008/2009 in Nepalese patients with fever visiting hospitals of Mahendranagar, Dhangadi and Dang. Serum samples were collected from 283 patients visiting hospital with history of fever & clinically suspected DF. The sero-prevalence of dengue virus specific 1gM was determined by enzyme linked immunosorbent assay (ELISA) kit (PanBio, Australia). The anti-dengue 1gM positivity was found to be 9.8%. The positive dengue cases were higher in female (10.9%) as compared to male (9.0%). Out of total positive cases, the highest positive cases (10.7%) were from age group above 50 years followed by 15-50 years age group with 10.1%. Out of 3 hospitals, the highest positive cases were in Mahakali Zonal Hospital, Mahendranagar (13.3%) followed by Seti Zonal hospital, Dhangadi ( 9.8%). Age and gender were found to be independent predictors. The highest numbers of dengue positive cases were in Ethnic group Brahman/Chherti ( 13.1%) followed by Janajati (5.6%). The highest numbers of dengue positive cases were in occupation group Agriculture (12.0%) followed by student (11.5%). The association between dengue disease and ethnic group & occupation was not statistically significant. Molecular diagnosis based on RT-PCR was also performed to optimize the conditions and confirmatory diagnosis in the acute samples. However, none of the tested sample showed positivity. The 1gM capture ELISA has become the most accepted technique for the diagnosis of dengue in developing countries like Nepal. The sero-prevalence of dengue has marginally increased the concerned authority should initiate extensive surveillance of dengue virus infection and commence an integrated vector control programme in order to abate from a panic viral disease outbreak in the Western Terai region of Nepal in the future. Key words: Dengue fever, 1gM Capture ELISA, RT-PCR, Terai region.

Eng.