Are anemia and blood group types related to Japanese encephalitis and dengue?

Introduction: Dengue and Japanese encephalitis (JE) are flaviviruses causing significant morbidity and mortality worldwide. Previous studies had found an association between dengue infection and particular blood group antigen and also the susceptibility to aplastic anemia by dengue. Aims and Objective: The present study was conducted to find any association between dengue and JE immunoglobulin G (IgG) antibody with blood group antigen or anemia. Methodology: The study was conducted in 2 slums of Delhi in 2013 in the interepidemic period. 5 mL blood from 239 samples were taken and processed for IgG levels of dengue and JE and rest used to test hemoglobin and blood group. Results and Discussion: No association has been found between blood group types and dengue IgG antibody positivity (P = 0.42) or JE IgG antibody positivity (P = 0.148). Nor did anemia established any association with dengue (P = 0.185) or JE IgG antibody (P = 0.277). IgG status of dengue and JE could be used as proxy markers of any past subclinical infection (includes clinically manifested cases also). Further studies in large settings and other areas could be done to validate the results. This was the first study of its kind in such settings.