In a worrying development in Delhi, the capital is registering a rise in co-infection of dengue and COVID-19, with doctors warning that this combination could enhance the severity of both diseases. Most cases of COVID-19 and dengue are asymptomatic, and in a setting of co-infection, one disease might enhance the severity of the other. What's even more challenging is that both the viral diseases do not have any specific antiviral drug or vaccine and therefore, treatment depends on clinical conditions and symptoms. We speak with Dr Shuchin Bajaj, founder and director of Ujala Cygnus group of hospitals.