Naomi Lazarus

California State University Chico

COVID-19 Incidence and Mortality maps

For my GSF project, I will be conducting a county-level assessment of COVID-19 in relation to age demographics and comorbidities.  I am currently in the data collection phase.  Raw data on daily cases and deaths are obtained from USAFacts (, which is the source data used by the CDC to develop their surveillance of COVID-19 cases and deaths. Incidence rates (per 100,000 of population) and death-to-case ratios (per 100 of population) are calculated for two peak periods of the virus.  The first peak occurred during 03/01/20 to 04/30/20 and peak 2 from 06/01/20 to 07/31/20.  The dataset on incidence and mortality was compiled by undergraduate students working in the GeoPlace map lab that I run at Chico State.  They have also produced some preliminary maps for the first and second peak periods of the virus.  The featured maps refer to incidence rates and mortality during the second wave of the virus that took place between 06/01/20 and 07/31/20.

The map on incidence rates shows clusters of counties in the south and southwestern United States with incidence rates greater than 3,000 per 100,000 of the population.  Counties in the northeast and mid-west are recording lower incidence rates after the mitigation strategies enforced following the initial surge in cases during the first peak period that began in March 2020.

The spatial pattern of the death-to-case ratio is more dispersed than case incidence rates.  Some counties in the northeast and several in the interior of the country recorded death-to-case ratios of 33% or higher (33 per 100 of population).  Counties in the south and southwestern regions are recording lower death-to-case ratios compared to their high incidence rates.



Naomi Lazarus

Dr. Naomi W. Lazarus is an Assistant Professor of Geosciences in the Department of Geography and Planning at California State University, Chico. She earned her B.A. and M.A. in Geography at Binghamton University, New York and has a PhD in Geography from the University of Connecticut, Storrs. Dr. Lazarus’ research examines the demographic, social, and economic impacts of natural and anthropogenic hazards. Her current research examines spatial and temporal trends in the dengue virus in South Asia. Dr. Lazarus teaches courses in GIS, cartography, and quantitative methods at CSU Chico.


Name and email are required. Your email will not be published.

Please provide a username.
Please provide a valid email
Please input your message.