Background Dengue virus (DENV) infection is an important public health problem and causes significant morbidity and mortality. DENV typically causes a febrile illness that ranges from mild asymptomatic infection to fatal dengue hemorrhagic fever (DHF) and/or dengue shock syndrome (DSS). Early prediction of severe dengue disease is of utmost importance for providing prompt monitoring and treatment. The search for an ideal biomarker (host or viral factors) for early prediction of severe dengue remains elusive. Aim To standardize a real time qRT-PCR for quantifying dengue viremia in serum samples and evaluate the kinetics of dengue viremia and its significance in disease severity. Results In this ambispective study of 126 laboratory confirmed dengue patients, 72 were primary infections and 54 were secondary infections. The most common serotype was serotype 1 (n = 37) followed by serotype 2 (n = 34). According to WHO 1997 dengue case classification, 111 patients were cases of dengue fever (DF), 13 from DHF and 02 from DSS. Day 3 viremia levels were significantly elevated in severe dengue patients (DHF/DSS) as compared to that of DF ( p  < 0.05). However, no such association was found between viremia levels and serotype or immune status. Conclusion Dengue viremia has a significant association with disease severity and day 3 viremia levels may be used as a predictor for dengue disease severity.