Pathology informs and structures urban spaces. This article explores the relationship between the urban and the pathological by trailing the
Aedes
mosquito, the dengue vector, to trace the intersection of the civic, social, ecological, and political in the everyday life of Delhi. To control the possibility of a dengue epidemic, the gaze of public health authorities primarily focuses on areas considered inherently “dirty”—localities of East Delhi at the margins of the city, situated at Yamuna riverfront, populated by working-class migrants living in unauthorized colonies. The residents of such areas, however, have to deal with the absence of basic urban infrastructure on one hand, while also being under the stringent administrative glare for pest control. Interestingly, both the inhabitants of these areas and their administrators express the ungovernable stubbornness of such regions using the colloquial expression “
Khula
area.” Based on a multi-sited ethnography, this work follows many usages of the term Khula by several actors across the city, including scientists, city administrators, and frontline workers. Then, it argues that the word Khula is an empty signifier, which, through many of its meanings, enables us to see urban spaces through the prism of the pathological and all things that fall within its shadow.