RESUMO
Background: The most challenging problem associated with patient management in Dengue infection is early diagnosis. Secondary infection with dengue virus is the most accepted risk factor for the development of dengue haemorrhagic fever. Serologic diagnosis of dengue virus infection using ELISA of both IgM and IgG distinguishes primary and secondary infections. Aim: To determine the prevalence of Dengue Fever in Thoothukudi, the coastal district of Tamilnadu by serological tests IgM ELISA and IgG ELISA, to compare the IgM and IgG status of the dengue cases to differentiate between the primary and secondary dengue cases. Methods: A cross sectional comparative study in patients with fever suspicious of dengue, fevers with other causes excluded. Detailed history is obtained and complete clinical examination done. IgM and IgG Elisa test were performed. Results: Out of 50 patients, 28 (56%) were positive for dengue and 22 (44%) were negative. 13 cases had primary Dengue (IgM positive) and 15 had secondary Dengue (IgM and IgG positive and IgG positive). Among the 28 positive cases 16 are paediatric, 10 cases had hemorrhagic manifestations, all were secondary dengue. Conclusion: As this study was conducted during an outbreak in Thoothukudi, unusually high prevalence is seen particularly among the pediatric ages. Higher morbidity is seen in secondary dengue cases. Thus, early discrimination of primary and secondary dengue helps to reduce the morbidity and mortality.