Fig. 2: COVID-19 onset timing across districts.
From: Characterizing COVID-19 waves in urban and rural districts of India

Estimated COVID-19 wave onset month for the first (a) and the second (b) wave across districts. Districts with no data are filled with gray color. Spatial patterns of onset months for the first wave (left) highlight multiple leading districts, whereas the second-wave (right) patterns emphasize a few concentrated leading districts.