Now more than ever, it is essential that we understand where people are located, what conditions they are facing, what infrastructure is available, and what basic services they can access. Fortunately, gridded population data have emerged as an important resource for delivering actionable data in challenging circumstances, including in disaster response and health and infectious disease monitoring.

A new mapping tool shows the density of population in relationship to reported coronavirus disease (COVID-19) cases at national and sub-national levels, and permits users to obtain custom estimates of the number of people by age and sex living in an area of interest, including areas not currently reporting large numbers of cases.